Fix usage of PolygonRoi and other ROIs that depend on ij.gui.ImageCanvas.mouseMoved

[trakem2.git] / TrakEM2_ / src / main / java / ini / trakem2 / display / DisplayCanvas.java

/**

 TrakEM2 plugin for ImageJ(C).
 Copyright (C) 2005-2009 Albert Cardona and Rodney Douglas.

 This program is free software; you can redistribute it and/or
 modify it under the terms of the GNU General Public License
 as published by the Free Software Foundation (http://www.gnu.org/licenses/gpl.txt )

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

 You may contact Albert Cardona at acardona at ini.phys.ethz.ch
 Institute of Neuroinformatics, University of Zurich / ETH, Switzerland.
 **/

package ini.trakem2.display;

import java.awt.AWTException;
import java.awt.AlphaComposite;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Component;
import java.awt.Composite;
import java.awt.Cursor;
import java.awt.Event;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GraphicsConfiguration;
import java.awt.Image;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.RenderingHints;
import java.awt.Robot;
import java.awt.Stroke;
import java.awt.Toolkit;
import java.awt.Transparency;
import java.awt.event.InputEvent;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseWheelEvent;
import java.awt.event.MouseWheelListener;
import java.awt.geom.AffineTransform;
import java.awt.geom.Area;
import java.awt.geom.Ellipse2D;
import java.awt.image.BufferedImage;
import java.awt.image.PixelGrabber;
import java.awt.image.VolatileImage;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
import java.util.Map;
import java.util.Set;
import java.util.Vector;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;

import org.scijava.vecmath.Point2f;
import org.scijava.vecmath.Vector2f;
import org.scijava.vecmath.Vector3d;

import ij.IJ;
import ij.ImagePlus;
import ij.Prefs;
import ij.WindowManager;
import ij.gui.ImageCanvas;
import ij.gui.Roi;
import ij.gui.Toolbar;
import ij.measure.Calibration;
import ij.process.ByteProcessor;
import ij.process.ColorProcessor;
import ini.trakem2.Project;
import ini.trakem2.display.graphics.GraphicsSource;
import ini.trakem2.display.inspect.InspectPatchTrianglesMode;
import ini.trakem2.imaging.Segmentation;
import ini.trakem2.persistence.Loader;
import ini.trakem2.utils.Bureaucrat;
import ini.trakem2.utils.IJError;
import ini.trakem2.utils.Lock;
import ini.trakem2.utils.ProjectToolbar;
import ini.trakem2.utils.Search;
import ini.trakem2.utils.Utils;
import ini.trakem2.utils.Worker;

public final class DisplayCanvas extends ImageCanvas implements KeyListener/*, FocusListener*/, MouseWheelListener {

        private static final long serialVersionUID = 1L;

        private Display display;

        private boolean update_graphics = false;
        private BufferedImage offscreen = null;
        private final HashSet<BufferedImage> to_flush = new HashSet<BufferedImage>();
        private ArrayList<Displayable> al_top = new ArrayList<Displayable>();

        private final Lock lock_paint = new Lock();

        private Rectangle box = null; // the bounding box of the active

        private FakeImageWindow fake_win;

        private FreeHandProfile freehandProfile = null;
        private Robot r;// used for setting the mouse pointer

        private final Object offscreen_lock = new Object();

        private Cursor noCursor;

        private boolean snapping = false;
        private boolean dragging = false;
        private boolean input_disabled = false;
        private boolean input_disabled2 = false;

        /** Store a copy of whatever data as each Class may define it, one such data object per class.
         * Private to the package. */
        static private Hashtable<Class<?>,Object> copy_buffer = new Hashtable<Class<?>,Object>();

        static void setCopyBuffer(final Class<?> c, final Object ob) { copy_buffer.put(c, ob); }
        static Object getCopyBuffer(final Class<?> c) { return copy_buffer.get(c); }

        static private boolean openglEnabled = false;
        static private boolean quartzEnabled = false;
        static private boolean ddscaleEnabled = false;

        // Private to the display package:
        static final RenderingHints rhints;

        /** Adapted code from Wayne Meissner, for gstreamer-java org.gstreamer.swing.GstVideoComponent; */
        static {
                final Map<RenderingHints.Key, Object> hints = new HashMap<RenderingHints.Key, Object>();
                try {
                        final String openglProperty = System.getProperty("sun.java2d.opengl");
                        openglEnabled = openglProperty != null && Boolean.parseBoolean(openglProperty);
                } catch (final Exception ex) { }
                try {
                        final String quartzProperty = System.getProperty("apple.awt.graphics.UseQuartz");
                        quartzEnabled = Boolean.parseBoolean(quartzProperty);
                } catch (final Exception ex) { }
                try {
                        final String ddscaleProperty = System.getProperty("sun.java2d.ddscale");
                        final String d3dProperty = System.getProperty("sun.java2d.d3d");
                        ddscaleEnabled = Boolean.parseBoolean(ddscaleProperty) && Boolean.parseBoolean(d3dProperty);
                } catch (final Exception ex) { }

                if (openglEnabled) {
                        // Bilinear interpolation can be accelerated by the OpenGL pipeline
                        hints.put(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
                        hints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);

                } else if (quartzEnabled) {
                        //hints.put(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
                        hints.put(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_NEAREST_NEIGHBOR);
                        hints.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_SPEED);
                        hints.put(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF);

                } else if (ddscaleEnabled) {
                        hints.put(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
                }

                rhints = new RenderingHints(hints);
        }

        private VolatileImage volatileImage;
        private Object volatile_lock = new Object();
        //private javax.swing.Timer resourceTimer = new javax.swing.Timer(10000, resourceReaper);
        //private boolean frameRendered = false;
        private boolean invalid_volatile = false;

        /** Adapted code from Wayne Meissner, for gstreamer-java org.gstreamer.swing.GstVideoComponent.
         *  MUST be called within a "synchronized (volatile_lock) { ... }" block. */
        private void renderVolatileImage(final GraphicsConfiguration gc, final BufferedImage offscreen,
                        final ArrayList<Displayable> top, final Displayable active,
                        final Layer active_layer, final List<Layer> layers,
                        final int c_alphas, final AffineTransform at, Rectangle clipRect) {
                do {
                        // Recreate volatileImage ONLY if necessary: when null, when incompatible, or when dimensions have changed
                        // Otherwise, just paint on top of it
                        final int w = getWidth(), h = getHeight();
                        if (0 == w || 0 == h) return;
                        if (null == volatileImage || volatileImage.getWidth() != w
                          || volatileImage.getHeight() != h || volatileImage.validate(gc) == VolatileImage.IMAGE_INCOMPATIBLE) {
                                if (null != volatileImage) volatileImage.flush();
                                volatileImage = gc.createCompatibleVolatileImage(w, h);
                                volatileImage.setAccelerationPriority(1.0f);
                                invalid_volatile = false;
                                clipRect = null; // paint all
                        }
                        //
                        // Now paint the BufferedImage into the accelerated image
                        //
                        final Graphics2D g = volatileImage.createGraphics();

                        // 0 - set clipRect
                        if (null != clipRect) g.setClip(clipRect);

                        // 1 - Erase any background
                        g.setColor(Color.black);
                        if (null == clipRect) g.fillRect(0, 0, w, h);
                        else g.fillRect(clipRect.x, clipRect.y, clipRect.width, clipRect.height);

                        // 2 - Paint offscreen image
                        if (null != offscreen) g.drawImage(offscreen, 0, 0, null);

                        // 3 - Paint the active Displayable and all cached on top

                        //Object antialias = g.getRenderingHint(RenderingHints.KEY_ANTIALIASING);
                        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,  RenderingHints.VALUE_ANTIALIAS_ON); // to smooth edges of the images
                        //Object text_antialias = g.getRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING);
                        g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
                        //Object render_quality = g.getRenderingHint(RenderingHints.KEY_RENDERING);
                        g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);

                        if (null != active_layer) {
                                g.setTransform(at);
                                g.setStroke(this.stroke); // AFTER setting the transform
                                // Active has to be painted wherever it is, within al_top, if it's not an image
                                //if (null != active && active.getClass() != Patch.class && !active.isOutOfRepaintingClip(magnification, srcRect, clipRect)) active.paint(g, magnification, true, c_alphas, active_layer);
                                final boolean must_paint_active = null != active && active.isVisible() && !ImageData.class.isAssignableFrom(active.getClass());
                                boolean active_painted = !must_paint_active;

                                if (null != top) {
                                        final Rectangle tmp = null != clipRect ? new Rectangle() : null;
                                        final Rectangle clip = null != clipRect ? new Rectangle((int)(clipRect.x * magnification) - srcRect.x, (int)(clipRect.y * magnification) - srcRect.y, (int)(clipRect.width * magnification), (int)(clipRect.height * magnification)) : null;
                                        for (final Displayable d : top) {
                                                if (null != clipRect && !d.getBoundingBox(tmp).intersects(clip)) continue;
                                                d.paint(g, srcRect, magnification, d == active, c_alphas, active_layer, layers);
                                                if (active_painted) continue;
                                                else active_painted = d == active;
                                        }
                                }
                                if (must_paint_active && !active_painted) {
                                        // Active may not have been part of top array if it was added new and the offscreen image was not updated,
                                        // which is the case for any non-image object
                                        // Or, when selecting an object if there were none selected yet.
                                        active.paint(g, srcRect, magnification, true, c_alphas, active_layer, layers);
                                }
                        }

                        display.getMode().getGraphicsSource().paintOnTop(g, display, srcRect, magnification);

                        if (null != active_layer.getOverlay2())
                                active_layer.getOverlay2().paint(g, srcRect, magnification);
                        if (null != active_layer.getParent().getOverlay2())
                                active_layer.getParent().getOverlay2().paint(g, srcRect, magnification);

                        if (null != display.gridoverlay) display.gridoverlay.paint(g);

                        /* // debug: paint the ZDisplayable's bucket in this layer
                        if (null != active_layer.getParent().lbucks) {
                                active_layer.getParent().lbucks.get(active_layer).root.paint(g, srcRect, magnification, Color.red);
                        }
                        */

                        g.dispose();
                } while (volatileImage.contentsLost());
        }

        /** Adapted code from Wayne Meissner, for gstreamer-java org.gstreamer.swing.GstVideoComponent;
         *  Paints (and re-renders, if necessary) the volatile image onto the given Graphics object, which
         *  is that of the DisplayCanvas as provided to the paint(Graphics g) method.
         *
         *  Expects clipRect in screen coordinates
         */
        private void render(final Graphics g, final Displayable active, final Layer active_layer,
                        final List<Layer> layers, final int c_alphas, final AffineTransform at, Rectangle clipRect) {
                final Graphics2D g2d = (Graphics2D) g.create();
                g2d.setRenderingHints(rhints);
                do {
                        final ArrayList<Displayable> top;
                        final BufferedImage offscreen;
                        synchronized (offscreen_lock) {
                                offscreen = this.offscreen;
                                top = this.al_top; // will never be cleared, but may be swapped
                        }
                        final GraphicsConfiguration gc = getGraphicsConfiguration();
                        display.getProject().getLoader().releaseToFit(getWidth() * getHeight() * 4 * 5); // 5 images

                        // Protect volatile image while rendering it
                        synchronized (volatile_lock) {
                                if (invalid_volatile || null == volatileImage
                                 || volatileImage.validate(gc) != VolatileImage.IMAGE_OK)
                                {
                                        // clear clip, remade in full
                                        clipRect = null;
                                        renderVolatileImage(gc, offscreen, top, active, active_layer, layers, c_alphas, at, clipRect);
                                }
                                if (null != clipRect) g2d.setClip(clipRect);
                                g2d.drawImage(volatileImage, 0, 0, null);
                        }
                } while (volatileImage.contentsLost());

                g2d.dispose();

                // Flush all old offscreen images
                synchronized (offscreen_lock) {
                        for (final BufferedImage bi : to_flush) {
                                bi.flush();
                        }
                        to_flush.clear();
                }
        }

        protected void invalidateVolatile() {
                synchronized (volatile_lock) {
                        this.invalid_volatile = true;
                }
        }

        /////////////////

        public DisplayCanvas(final Display display, final int width, final int height) {
                super(new FakeImagePlus(width, height, display));
                fake_win = new FakeImageWindow(imp, this, display);
                this.display = display;
                this.imageWidth = width;
                this.imageHeight = height;
                removeKeyListener(IJ.getInstance());
                addKeyListener(this);
                addMouseWheelListener(this);
        }

        public Display getDisplay() { return display; }

        /** Used to constrain magnification so that only snapshots are used for painting when opening a new, large and filled Display. */
        protected void setInitialMagnification(final double mag) { // calling this method 'setMagnification' would conflict with the super class homonimous method.
                this.magnification = mag; // don't save in the database. This value is overriden when reopening from the database by calling the setup method.
        }

        /** Used for restoring properties from the database. */
        public void setup(final double mag, final Rectangle srcRect) {
                this.magnification = mag;
                this.srcRect = (Rectangle)srcRect.clone(); // just in case
                super.setDrawingSize((int)Math.ceil(srcRect.width * mag), (int)Math.ceil(srcRect.height * mag));
                setMagnification(mag);
                //no longer needed//display.pack(); // TODO should be run via invokeLater ... need to check many potential locks of invokeLater calling each other.
        }

        /** Does not repaint. */
        public void setDimensions(final double width, final double height) {
                this.imageWidth = (int)Math.ceil(width);
                this.imageHeight = (int)Math.ceil(height);
                ((FakeImagePlus)imp).setDimensions(imageWidth, imageHeight);
        }

        /** Overriding to disable it. */
        public void handlePopupMenu() {}

        @Override
        public final void update(final Graphics g) {
                // overriding to avoid default behaviour in java.awt.Canvas which consists in first repainting the entire drawable area with the background color, and then calling method paint.
                this.paint(g);
        }

        /** Handles repaint event requests and the generation of offscreen threads. */
        private final AbstractRepaintThread RT = new AbstractRepaintThread(this, "T2-Canvas-Repainter", new OffscreenThread()) {
                @Override
                protected void handleUpdateGraphics(final Component target, final Rectangle clipRect) {
                        final Layer active_layer = display.getLayer();
                        this.off.setProperties(new RepaintProperties(clipRect, active_layer, active_layer.getParent().getColorCueLayerRange(active_layer), target.getWidth(), target.getHeight(), srcRect, magnification, display.getActive(), display.getDisplayChannelAlphas(), display.getMode().getGraphicsSource()));
                }
        };

        /*
        private final void setRenderingHints(final Graphics2D g) {
                // so slow!! Particularly the first one.
                g.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BICUBIC);
                //g.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
                //g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,  RenderingHints.VALUE_ANTIALIAS_ON); // to smooth edges of the images
                //g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
                //g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
        }
        */

        @Override
        public void setMagnification(double mag) {
                if (mag < 0.00000001) mag = 0.00000001;
                // ensure a stroke of thickness 1.0 regardless of magnification
                this.stroke = new BasicStroke((float)(1.0/mag), BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER);
                // FIXES MAG TO ImageCanvas.zoomLevel LIMITS!!
                //super.setMagnification(mag);
                // So, manually:
                this.magnification = mag;
                imp.setTitle(imp.getTitle());
                display.getMode().magnificationUpdated(srcRect, mag);
        }

        /** Paint lines always with a thickness of 1 pixel. This stroke is modified when the magnification is changed, to compensate. */
        private BasicStroke stroke = new BasicStroke(1.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER);

        /** The affine transform representing the srcRect displacement and the magnification. */
        private final AffineTransform atc = new AffineTransform();

        @Override
        public void paint(final Graphics g) {
                if (null == g) return;
                try {
                        synchronized (lock_paint) {
                                lock_paint.lock();
                        }

                        // ensure proper positioning
                        g.translate(0, 0); // ints!

                        final Rectangle clipRect = g.getClipBounds();

                        final Displayable active = display.getActive();
                        final int c_alphas = display.getDisplayChannelAlphas();

                        final Layer active_layer = display.getLayer();
                        final List<Layer> layers = active_layer.getParent().getColorCueLayerRange(active_layer);

                        final Graphics2D g2d = (Graphics2D)g;

                        // prepare the canvas for the srcRect and magnification
                        final AffineTransform at_original = g2d.getTransform();
                        atc.setToIdentity();
                        atc.scale(magnification, magnification);
                        atc.translate(-srcRect.x, -srcRect.y);
                        at_original.preConcatenate(atc);

                        if (null != offscreen && dragging) invalidateVolatile(); // to update the active at least
                        render(g, active, active_layer, layers, c_alphas, at_original, clipRect);

                        g2d.setTransform(at_original);

                        g2d.setStroke(this.stroke);

                        // debug buckets
                        //if (null != display.getLayer().root) display.getLayer().root.paint(g2d, srcRect, magnification, Color.red);
                        //if (null != display.getLayer().getParent().lbucks.get(display.getLayer()).root) display.getLayer().getParent().lbucks.get(display.getLayer()).root.paint(g2d, srcRect, magnification, Color.blue);


                        // reset to identity
                        g2d.setTransform(new AffineTransform());
                        // reset to 1.0 thickness
                        g2d.setStroke(new BasicStroke(1.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER));

                        // paint brush outline for AreaList, or fast-marching area
                        if (mouse_in && null != active && AreaContainer.class.isInstance(active)) {
                                switch (ProjectToolbar.getToolId()) {
                                        case ProjectToolbar.BRUSH:
                                                final int brushSize = ProjectToolbar.getBrushSize();
                                                g.setColor(active.getColor());
                                                g.drawOval((int)((xMouse -srcRect.x -brushSize/2)*magnification), (int)((yMouse - srcRect.y -brushSize/2)*magnification), (int)(brushSize * magnification), (int)(brushSize * magnification));
                                                break;
                                        case ProjectToolbar.PENCIL:
                                        case ProjectToolbar.WAND:
                                                final Composite co = g2d.getComposite();
                                                if (IJ.isWindows()) g2d.setColor(Color.yellow);
                                                else g2d.setXORMode(Color.yellow); // XOR on yellow for best contrast
                                                g2d.drawRect((int)((xMouse -srcRect.x -Segmentation.fmp.width/2)  * magnification),
                                                             (int)((yMouse -srcRect.y -Segmentation.fmp.height/2) * magnification),
                                                             (int)(Segmentation.fmp.width  * magnification),
                                                             (int)(Segmentation.fmp.height * magnification));
                                                g2d.setComposite(co); // undo XOR mode
                                                break;
                                }
                        }


                        final Roi roi = imp.getRoi();
                        if (null != roi) {
                                roi.draw(g);
                        }

                        // Mathias code:
                        if (null != freehandProfile) {
                                freehandProfile.paint(g, magnification, srcRect, true);
                                if(noCursor == null)
                                        noCursor = Toolkit.getDefaultToolkit().createCustomCursor(new BufferedImage(1,1,BufferedImage.TYPE_BYTE_BINARY), new Point(0,0), "noCursor");
                        }

                } catch (final Exception e) {
                        Utils.log2("DisplayCanvas.paint(Graphics) Error: " + e);
                        IJError.print(e);
                } finally {
                        synchronized (lock_paint) {
                                lock_paint.unlock();
                        }
                }
        }

        public void waitForRepaint() {
                // wait for all offscreen methods to finish painting
                RT.waitForOffs();
                // wait for the paint method to finish painting
                synchronized (lock_paint) {
                        lock_paint.lock();
                        lock_paint.unlock();
                }
        }

        /** Paints a handle on the screen coords. Adapted from ij.gui.Roi class. */
        static public void drawHandle(final Graphics g, final int x, final int y, final double magnification) {
                final int width5 = (int)(5 / magnification + 0.5);
                final int width3 = (int)(3 / magnification + 0.5);
                final int corr2 = (int)(2 / magnification + 0.5);
                final int corr1 = (int)(1 / magnification + 0.5);
                g.setColor(Color.white);
                g.drawRect(x - corr2, y - corr2, width5, width5);
                g.setColor(Color.black);
                g.drawRect(x - corr1, y - corr1, width3, width3);
                g.setColor(Color.white);
                g.fillRect(x, y, corr1, corr1);
        }

        /** Paints a handle at x,y screen coords. */
        static public void drawScreenHandle(final Graphics g, final int x, final int y) {
                g.setColor(Color.orange);
                g.drawRect(x - 2, y - 2, 5, 5);
                g.setColor(Color.black);
                g.drawRect(x - 1, y - 1, 3, 3);
                g.setColor(Color.orange);
                g.fillRect(x, y, 1, 1);
        }

        /** Paints a handle on the offscreen x,y. Adapted from ij.gui.Roi class. */
        /*
        private void drawHandle(Graphics g, double x, double y) {
                g.setColor(Color.black);
                g.fillRect((int) ((x - srcRect.x) * magnification) - 1, (int) ((y - srcRect.y) * magnification) - 1, 3, 3);
                g.setColor(Color.white);
                g.drawRect((int) ((x - srcRect.x) * magnification) - 2, (int) ((y - srcRect.y) * magnification) - 2, 5, 5);
        }
        */

        static protected BasicStroke DEFAULT_STROKE = new BasicStroke(1.0f, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER);
        static protected AffineTransform DEFAULT_AFFINE = new AffineTransform();

        static public void drawHandle(final Graphics2D g, final double x, final double y, final Rectangle srcRect, final double magnification) {
                final AffineTransform original = g.getTransform();
                g.setTransform(DEFAULT_AFFINE);
                final Stroke st = g.getStroke();
                g.setStroke(DEFAULT_STROKE);

                g.setColor(Color.black);
                g.fillRect((int) ((x - srcRect.x) * magnification) - 1, (int) ((y - srcRect.y) * magnification) - 1, 3, 3);
                g.setColor(Color.white);
                g.drawRect((int) ((x - srcRect.x) * magnification) - 2, (int) ((y - srcRect.y) * magnification) - 2, 5, 5);

                g.setStroke(st);
                g.setTransform(original);
        }

        /** As offscreen. */
        private int x_p, y_p, x_d, y_d, x_d_old, y_d_old;

        private boolean popup = false;

        private boolean locked = false;

        private int tmp_tool = -1;

        /** In world coordinates. */
        protected Point last_popup = null;

        protected Point consumeLastPopupPoint() {
                final Point p = last_popup;
                last_popup = null;
                return p;
        }

        @Override
        public void mousePressed(final MouseEvent me) {

                super.flags = me.getModifiers();

                x_p = x_d = srcRect.x + (int) (me.getX() / magnification); // offScreenX(me.getX());
                y_p = y_d = srcRect.y + (int) (me.getY() / magnification); // offScreenY(me.getY());

                this.xMouse = x_p;
                this.yMouse = y_p;

                // ban if beyond bounds:
                if (x_p < srcRect.x || y_p < srcRect.y || x_p > srcRect.x + srcRect.width || y_p > srcRect.y + srcRect.height) {
                        return;
                }

                // Popup:
                popup = false; // not reset properly in macosx
                if (Utils.isPopupTrigger(me)) {
                        popup = true;
                        last_popup = new Point(x_p, y_p);
                        display.getPopupMenu().show(this, me.getX(), me.getY());
                        return;
                }

                // reset
                snapping = false;

                int tool = ProjectToolbar.getToolId();

                // pan with middle mouse like in inkscape
                /* // works, but can't use it: the alt button then is useless (so no erasing with areas, and so on)
                if (0 != (flags & InputEvent.BUTTON2_MASK))
                */
                if (me.getButton() == MouseEvent.BUTTON2) {
                        tmp_tool = tool;
                        ProjectToolbar.setTool(Toolbar.HAND);
                        tool = Toolbar.HAND;
                }
                //Utils.log2("button: " + me.getButton() + "  BUTTON2: " + MouseEvent.BUTTON2);

                if (!zoom_and_pan) {
                        // stop animations when clicking (and on pushing ESC)
                        cancelAnimations();
                }

                switch (tool) {
                case Toolbar.MAGNIFIER:
                        if (me.isAltDown()) zoomOut(me.getX(), me.getY());
                        else zoomIn(me.getX(), me.getY());
                        return;
                case Toolbar.HAND:
                        super.setupScroll(x_p, y_p); // offscreen coords.
                        return;
                }

                if (input_disabled) {
                        input_disabled2 = true;
                        Utils.showMessage("Please wait while completing the task.\nOnly the glass and hand tool are enabled.");
                        return; // only zoom and pan are allowed
                }

                Displayable active = display.getActive();

                if (isTransforming() && ProjectToolbar.SELECT != tool) {
                        Utils.logAll("Notice: the 'Select' tool is not active!\n Activate the 'Select' tool to operate transformation modes.");
                }

                switch (tool) {
                case ProjectToolbar.PENCIL:
                        if (null != active && active.isVisible() && active.getClass() == Profile.class) {
                                final Profile prof = (Profile) active;
                                this.freehandProfile = new FreeHandProfile(prof);
                                freehandProfile.mousePressed(x_p, y_p);
                                return;
                        }
                        break;
                case Toolbar.RECTANGLE:
                case Toolbar.OVAL:
                case Toolbar.POLYGON:
                case Toolbar.FREEROI:
                case Toolbar.LINE:
                case Toolbar.POLYLINE:
                case Toolbar.FREELINE:
                case Toolbar.ANGLE:
                case Toolbar.POINT:
                        // pass the mouse event to superclass ImageCanvas.
                        super.mousePressed(me);
                        repaint();
                        return;
                case Toolbar.DROPPER:
                        // The color dropper
                        setDrawingColor(x_p, y_p, me.isAltDown());
                        return;
                }

                // check:
                if (display.isReadOnly()) return;

                switch (tool) {
                case Toolbar.TEXT:
                        if (!isTransforming()) {
                                // edit a label, or add a new one
                                if (null == active || !active.contains(x_p, y_p)) {
                                        // find a Displayable to activate, if any
                                        display.choose(me.getX(), me.getY(), x_p, y_p, DLabel.class);
                                        active = display.getActive();
                                }
                                if (null != active && active.isVisible() && active instanceof DLabel) {
                                        // edit
                                        ((DLabel) active).edit();
                                } else {
                                        // new
                                        final DLabel label = new DLabel(display.getProject(), "  ", x_p, y_p);
                                        display.getLayer().add(label);
                                        label.edit();
                                }
                        }
                        return;
                }

                // SPECIFIC for SELECT and above tools

                // no ROIs allowed past this point
                if (tool >= ProjectToolbar.SELECT) imp.killRoi();
                else return;

                Selection selection = display.getSelection();
                if (isTransforming()) {
                        box = display.getMode().getRepaintBounds();
                        display.getMode().mousePressed(me, x_p, y_p, magnification);
                        return;
                }
                // select or deselect another active Displayable, or add it to the selection group:
                if (ProjectToolbar.SELECT == tool) {
                        display.choose(me.getX(), me.getY(), x_p, y_p, me.isShiftDown(), null);
                }
                active = display.getActive();
                selection = display.getSelection();

                if (null == active || !active.isVisible()) return;

                switch (tool) {
                case ProjectToolbar.SELECT:
                        // gather initial box (for repainting purposes)
                        box = display.getMode().getRepaintBounds();
                        // check if the active is usable:
                        // check if the selection contains locked objects
                        if (selection.isLocked()) {
                                locked = true;
                                return;
                        }
                        display.getMode().mousePressed(me, x_p, y_p, magnification);
                        break;
                default: // the PEN and PENCIL tools, and any other custom tool
                        display.getLayerSet().addPreDataEditStep(active);
                        box = active.getBoundingBox();
                        active.mousePressed(me, display.getLayer(), x_p, y_p, magnification);
                        invalidateVolatile();
                        break;
                }
        }

        @Override
        public void mouseDragged(final MouseEvent me) {

                super.flags = me.getModifiers();

                if (popup) return;

                // ban if beyond bounds:
                if (x_p < srcRect.x || y_p < srcRect.y || x_p > srcRect.x + srcRect.width || y_p > srcRect.y + srcRect.height) {
                        return;
                }

                if (ProjectToolbar.SELECT == ProjectToolbar.getToolId() && locked) {
                        Utils.log2("Selection is locked.");
                        return;
                }

                dragging = true;

                x_d_old = x_d;
                y_d_old = y_d;

                x_d = srcRect.x + (int) (me.getX() / magnification); // offscreen
                y_d = srcRect.y + (int) (me.getY() / magnification);

                this.xMouse = x_d;
                this.yMouse = y_d;

                // protection:
                final int me_x = me.getX();
                final int me_y = me.getY();
                if (me_x < 0 || me_x > this.getWidth() || me_y < 0 || me_y > this.getHeight()) {
                        x_d = x_d_old;
                        y_d = y_d_old;
                        return;
                }

                final int tool = ProjectToolbar.getToolId();


                // pan with middle mouse like in inkscape
                /* // works, but can't use it: the alt button then is useless (so no erasing with areas, and so on)
                if (0 != (flags & InputEvent.BUTTON2_MASK)) {
                        tool = Toolbar.HAND;
                }
                */ // so the above has been implemented as a temporary switch to the HAND tool at the mousePressed function.

                switch (tool) {
                case Toolbar.MAGNIFIER: // TODO : create a zooms-area tool
                        return;
                case Toolbar.HAND:
                        final int srx = srcRect.x,
                            sry = srcRect.y;
                        scroll(me.getX(), me.getY());
                        if (0 != srx - srcRect.x || 0 != sry - srcRect.y) {
                                update_graphics = true; // update the offscreen images.
                                display.getNavigator().repaint(false);
                                repaint(true);
                        }
                        return;
                }

                if (input_disabled2) return;

                //debug:
                //Utils.log2("x_d,y_d : " + x_d + "," + y_d + "   x_d_old, y_d_old : " + x_d_old + "," + y_d_old + "  dx, dy : " + (x_d_old - x_d) + "," + (y_d_old - y_d));

                // Code for Matthias' FreehandProfile (TODO this should be done on mousePressed, not on mouseDragged)

                final Displayable active = display.getActive();
                if (null != active && active.getClass() == Profile.class) {
                        try {
                                if (r == null) {
                                        r = new Robot(this.getGraphicsConfiguration().getDevice());
                                }
                        } catch (final AWTException e) {
                                e.printStackTrace();
                        }
                }

                switch (tool) {
                case ProjectToolbar.PENCIL:
                        if (null != active && active.isVisible() && active.getClass() == Profile.class) {
                                if (freehandProfile == null)
                                        return; // starting painting out of the DisplayCanvas border
                                final double dx = x_d - x_d_old;
                                final double dy = y_d - y_d_old;
                                freehandProfile.mouseDragged(me, x_d, y_d, dx, dy);
                                repaint();
                                // Point screenLocation = getLocationOnScreen();
                                // mousePos[0] += screenLocation.x;
                                // mousePos[1] += screenLocation.y;
                                // r.mouseMove( mousePos[0], mousePos[1]);
                                return;
                        }
                        break;
                case Toolbar.RECTANGLE:
                case Toolbar.OVAL:
                case Toolbar.POLYGON:
                case Toolbar.FREEROI:
                case Toolbar.LINE:
                case Toolbar.POLYLINE:
                case Toolbar.FREELINE:
                case Toolbar.ANGLE:
                case Toolbar.POINT:
                        // pass the mouse event to superclass ImageCanvas.
                        super.mouseDragged(me);
                        repaint(false);
                        return;
                }
                // no ROIs beyond this point
                if (tool >= ProjectToolbar.SELECT) imp.killRoi();
                else return;

                // check:
                if (display.isReadOnly()) return;

                if (null != active && active.isVisible()) {
                        // prevent dragging beyond the layer limits
                        if (display.getLayer().contains(x_d, y_d, 1)) {
                                Rectangle box2;
                                switch (tool) {
                                case ProjectToolbar.SELECT:
                                        display.getMode().mouseDragged(me, x_p, y_p, x_d, y_d, x_d_old, y_d_old);
                                        box2 = display.getMode().getRepaintBounds();
                                        box.add(box2);
                                        // repaint all Displays (where it was and where it is now, hence the sum of both boxes):
                                        Display.repaint(display.getLayer(), Selection.PADDING, box, false, active.isLinked() || active.getClass() == Patch.class);
                                        // box for next mouse dragged iteration
                                        box = box2;
                                        break;
                                default:
                                        active.mouseDragged(me, display.getLayer(), x_p, y_p, x_d, y_d, x_d_old, y_d_old);
                                        // the line above must repaint on its own
                                        break;
                                }
                        } else {
                                //beyond_srcRect = true;
                                Utils.log("DisplayCanvas.mouseDragged: preventing drag beyond layer limits.");
                        }
                } else if (display.getMode() instanceof ManualAlignMode
                        || display.getMode() instanceof InspectPatchTrianglesMode) {
                        if (display.getLayer().contains(x_d, y_d, 1)) {
                                if (tool >= ProjectToolbar.SELECT) {
                                        display.getMode().mouseDragged(me, x_p, y_p, x_d, y_d, x_d_old, y_d_old);
                                }
                        }
                }
        }

        @Override
        public void mouseReleased(final MouseEvent me) {

                super.flags = me.getModifiers();

                final boolean dragging2 = dragging;
                dragging = false;
                final boolean locked2 = locked;
                locked = false;

                if (popup) {
                        popup = false;
                        return;
                }

                // ban if beyond bounds:
                if (x_p < srcRect.x || y_p < srcRect.y || x_p > srcRect.x + srcRect.width || y_p > srcRect.y + srcRect.height) {
                        return;
                }

                final int tool = ProjectToolbar.getToolId();

                // pan with middle mouse like in inkscape
                /* // works, but can't use it: the alt button then is useless (so no erasing with areas, and so on)
                if (0 != (flags & InputEvent.BUTTON2_MASK)) {
                        tool = Toolbar.HAND;
                }
                */

                switch (tool) {
                case Toolbar.MAGNIFIER:
                        // display.updateInDatabase("srcRect"); // TODO if the display.frame
                        // is shrinked, the pack() in the zoom methods will also call the
                        // updateInDatabase("srcRect") (so it's going to be done twice)
                        display.updateFrameTitle();
                        return;
                case Toolbar.HAND:
                        display.updateInDatabase("srcRect");
                        if (-1 != tmp_tool) {
                                ProjectToolbar.setTool(tmp_tool);
                                tmp_tool = -1;
                        }
                        if (!dragging2) repaint(true); // TEMPORARY just to allow fixing bad screen when simply cliking with the hand
                        display.getMode().srcRectUpdated(srcRect, magnification);
                        return;
                }

                if (input_disabled2) {
                        input_disabled2 = false; // reset
                        return;
                }

                if (locked2) {
                        if (ProjectToolbar.SELECT == tool) {
                                if (dragging2) {
                                        Utils.showMessage("Selection is locked!");
                                }
                                return;
                        }
                }

                // pan with middle mouse like in inkscape
                /* // works, but can't use it: the alt button then is useless (so no erasing with areas, and so on)
                if (0 != (flags & InputEvent.BUTTON2_MASK)) {
                        tool = Toolbar.HAND;
                }
                */

                super.flags &= ~InputEvent.BUTTON1_MASK; // make sure button 1 bit is not set
                super.flags &= ~InputEvent.BUTTON2_MASK; // make sure button 2 bit is not set
                super.flags &= ~InputEvent.BUTTON3_MASK; // make sure button 3 bit is not set

                final int x_r = srcRect.x + (int)(me.getX() / magnification);
                final int y_r = srcRect.y + (int)(me.getY() / magnification);

                /*
                if (beyond_srcRect) {
                        // Artificial release on the last dragged point
                        x_r = x_d;
                        y_r = y_d;
                }
                */

                this.xMouse = x_r;
                this.yMouse = y_r;

                final Displayable active = display.getActive();

                switch (tool) {
                        case ProjectToolbar.PENCIL:
                                if (null != active && active.isVisible() && active.getClass() == Profile.class) {
                                        if (freehandProfile == null)
                                                return; // starting painting out of the DisplayCanvas boarder
                                        freehandProfile.mouseReleased(me, x_p, y_p, x_d, y_d, x_r, y_r);
                                        freehandProfile = null;
                                        //repaint(true);
                                        final Selection selection = display.getSelection();
                                        selection.updateTransform(display.getActive());
                                        Display.repaint(display.getLayer(), selection.getBox(), Selection.PADDING); // repaints the navigator as well
                                        return;
                                }
                                break;
                        case Toolbar.RECTANGLE:
                        case Toolbar.OVAL:
                        case Toolbar.POLYGON:
                        case Toolbar.FREEROI:
                        case Toolbar.LINE:
                        case Toolbar.POLYLINE:
                        case Toolbar.FREELINE:
                        case Toolbar.ANGLE:
                        case Toolbar.POINT:
                                // pass the mouse event to superclass ImageCanvas.
                                super.mouseReleased(me);
                                repaint();
                                // return; // replaced by #SET_ROI
                }

                final Roi roi = imp.getRoi();

                // check:
                if (display.isReadOnly()) return;

                if (tool >= ProjectToolbar.SELECT) {
                        if (null != roi) imp.killRoi();
                } else return; // #SET_ROI

                final Selection selection = display.getSelection();

                if (snapping) {
                        // finish dragging
                        display.getMode().mouseReleased(me, x_p, y_p, x_d, y_d, x_r, y_r);
                        box.add(display.getMode().getRepaintBounds());
                        Display.repaint(display.getLayer(), box, Selection.PADDING); // repaints the navigator as well
                        Display.snap((Patch)active);
                        // reset:
                        snapping = false;
                        return;
                }

                if (null != active && active.isVisible()) {
                        switch(tool) {
                        case ProjectToolbar.SELECT:
                                display.getMode().mouseReleased(me, x_p, y_p, x_d, y_d, x_r, y_r);
                                box.add(display.getMode().getRepaintBounds());
                                Display.repaint(display.getLayer(), Selection.PADDING, box, !isTransforming(), active.isLinked() || active.getClass() == Patch.class); // does not repaint the navigator
                                break;
                        case ProjectToolbar.PENCIL:
                        case ProjectToolbar.PEN:
                        case ProjectToolbar.BRUSH:
                                active.mouseReleased(me, display.getLayer(), x_p, y_p, x_d, y_d, x_r, y_r); // active, not selection (Selection only handles transforms, not active's data editions)
                                // update active's bounding box
                                selection.updateTransform(active);
                                box.add(selection.getBox());
                                Display.repaint(display.getLayer(), Selection.PADDING, box, !isTransforming(), active.isLinked() || active.getClass() == Patch.class); // does not repaint the navigator
                                //if (!active.getClass().equals(AreaList.class)) Display.repaint(display.getLayer(), box, Selection.PADDING); // repaints the navigator as well
                                // TODO: this last repaint call is unnecessary, if the box was properly repainted on mouse drag for Profile etc.
                                //else
                                if (null != old_brush_box) {
                                        repaint(old_brush_box, 0, false);
                                        old_brush_box = null; // from mouseMoved
                                }
                                // The current state:
                                display.getLayerSet().addDataEditStep(active);
                                break;
                        }
                }
        }

        private boolean mouse_in = false;

        @Override
        public void mouseEntered(final MouseEvent me) {
                mouse_in = true;
                // try to catch focus if the JFrame is front most
                if (display.isActiveWindow() && !this.hasFocus()) {
                        this.requestFocus();
                }
                // bring dragged point to mouse pointer
                // TODO doesn't work as expected.
                /*
                Displayable active = display.getActive();
                int x = offScreenX(me.getX());
                int y = offScreenY(me.getY());
                if (null != active) {
                        active.snapTo(x, y, x_p, y_p);
                        x_p = x_d = x_d_old = x;
                        y_p = y_d = y_d_old = y;
                }
                */
                //Utils.log2("mouseEntered x,y: " + offScreenX(me.getX()) + "," + offScreenY(me.getY()));
        }

        @Override
        public void mouseExited(final MouseEvent me) {
                mouse_in = false;
                // paint away the circular brush if any
                if (ProjectToolbar.getToolId() == ProjectToolbar.BRUSH) {
                        final Displayable active = display.getActive();
                        if (null != active && active.isVisible() && AreaContainer.class.isInstance(active)) {
                                if (null != old_brush_box) {
                                        this.repaint(old_brush_box, 0);
                                        old_brush_box = null;
                                }
                        }
                }
        }

        /** Sets the cursor based on the current tool and cursor location. */
        @Override
        public void setCursor(final int sx, final int sy, final int ox, final int oy) {
                // copy of ImageCanvas.setCursor without the win==null
                xMouse = ox;
                yMouse = oy;
                final Roi roi = imp.getRoi();
                /*
                 * ImageWindow win = imp.getWindow(); if (win==null) return;
                 */
                if (IJ.spaceBarDown()) {
                        setCursor(handCursor);
                        return;
                }
                switch (Toolbar.getToolId()) {
                case Toolbar.MAGNIFIER:
                        if (IJ.isMacintosh())
                                setCursor(defaultCursor);
                        else
                                setCursor(moveCursor);
                        break;
                case Toolbar.HAND:
                        setCursor(handCursor);
                        break;
                case ProjectToolbar.SELECT:
                case ProjectToolbar.PENCIL:
                        setCursor(defaultCursor);
                        break;
                default: // selection tool

                        if (roi != null && roi.getState() != Roi.CONSTRUCTING && roi.isHandle(sx, sy) >= 0)
                                setCursor(handCursor);
                        else if (Prefs.usePointerCursor || (roi != null && roi.getState() != Roi.CONSTRUCTING && roi.contains(ox, oy)))
                                setCursor(defaultCursor);
                        else
                                setCursor(crosshairCursor);
                        break;
                }
        }
        /** Set the srcRect - used by the DisplayNavigator. */
        protected void setSrcRect(final int x, final int y, int width, int height) {
                if (width < 1) width = 1;
                if (height < 1) height = 1;
                this.srcRect.setRect(x, y, width, height);
                display.updateInDatabase("srcRect");
                display.getMode().srcRectUpdated(srcRect, magnification);
        }

        @Override
        public void setDrawingSize(final int new_width, final int new_height) {
                adjustSrcRect(new_width, new_height);
                super.setDrawingSize(new_width, new_height);
        }

        /** Adjust srcRect and internal variables to the canvas' bounds. */
        public void adjustDimensions() {
                final Rectangle r = getBounds();
                adjustSrcRect(r.width, r.height);
                super.dstWidth = r.width;
                super.dstHeight = r.height;
        }

        /** Adjust srcRect to new dimensions. */
        public void adjustSrcRect(final int new_width, final int new_height) {
                final double mag = super.getMagnification();
                // This method is very important! Make it fit perfectly.
                if (srcRect.width * mag < new_width) {
                        // expand
                        if (new_width > imageWidth * mag) {
                                // too large, limit
                                srcRect.x = 0;
                                srcRect.width = imageWidth;
                        } else {
                                srcRect.width = (int) Math.ceil(new_width / mag);
                                if (srcRect.x + srcRect.width > imageWidth) {
                                        srcRect.x = imageWidth - srcRect.width;
                                }
                        }
                } else {
                        // shrink
                        srcRect.width = (int) Math.ceil(new_width / mag);
                }
                if (srcRect.height * mag < new_height) {
                        // expand
                        if (new_height > imageHeight * mag) {
                                // too large, limit
                                srcRect.y = 0;
                                srcRect.height = imageHeight;
                        } else {
                                srcRect.height = (int) Math.ceil(new_height / mag);
                                if (srcRect.y + srcRect.height > imageHeight) {
                                        srcRect.y = imageHeight - srcRect.height;
                                }
                        }
                } else {
                        // shrink
                        srcRect.height = (int) Math.ceil(new_height / mag);
                }
        }

        private void zoomIn2(int x, int y) {
                // copy of ImageCanvas.zoomIn except for the canEnlarge is different and
                // there's no call to the non-existing ImageWindow
                if (magnification >= 32)
                        return;
                final double newMag = getHigherZoomLevel2(magnification);

                // zoom at point: correct mag drift
                final int cx = getWidth() / 2;
                final int cy = getHeight() / 2;
                final int dx = (int)(((x - cx) * magnification) / newMag);
                final int dy = (int)(((y - cy) * magnification) / newMag);
                x -= dx;
                y -= dy;

                // Adjust the srcRect to the new dimensions
                int w = (int) Math.round(dstWidth / newMag);
                if (w * newMag < dstWidth)
                        w++;
                if (w > imageWidth)
                        w = imageWidth;
                int h = (int) Math.round(dstHeight / newMag);
                if (h * newMag < dstHeight)
                        h++;
                if (h > imageHeight)
                        h = imageHeight;
                x = offScreenX(x);
                y = offScreenY(y);
                final Rectangle r = new Rectangle(x - w / 2, y - h / 2, w, h);
                if (r.x < 0)
                        r.x = 0;
                if (r.y < 0)
                        r.y = 0;
                if (r.x + w > imageWidth)
                        r.x = imageWidth - w;
                if (r.y + h > imageHeight)
                        r.y = imageHeight - h;
                srcRect = r;

                //display.pack();

                setMagnification(newMag);
                display.updateInDatabase("srcRect");
                display.repaintAll2(); // this repaint includes this canvas's repaint as well, but also the navigator, etc. // repaint();
        }

        private void zoomOut2(int x, int y) {
                //if (magnification <= 0.03125)
                //      return;
                final double newMag = getLowerZoomLevel2(magnification);

                // zoom at point: correct mag drift
                final int cx = getWidth() / 2;
                final int cy = getHeight() / 2;
                final int dx = (int)(((x - cx) * magnification) / newMag);
                final int dy = (int)(((y - cy) * magnification) / newMag);
                x -= dx;
                y -= dy;

                if (imageWidth * newMag > dstWidth || imageHeight * newMag > dstHeight) {
                        int w = (int) Math.round(dstWidth / newMag);
                        if (w * newMag < dstWidth)
                                w++;
                        int h = (int) Math.round(dstHeight / newMag);
                        if (h * newMag < dstHeight)
                                h++;
                        x = offScreenX(x);
                        y = offScreenY(y);
                        final Rectangle r = new Rectangle(x - w / 2, y - h / 2, w, h);
                        if (r.x < 0)
                                r.x = 0;
                        if (r.y < 0)
                                r.y = 0;
                        if (r.x + w > imageWidth)
                                r.x = imageWidth - w;
                        if (r.y + h > imageHeight)
                                r.y = imageHeight - h;
                        srcRect = r;
                } else {
                        // Shrink srcRect, but NOT the dstWidth,dstHeight of the canvas, which remain the same:
                        srcRect = new Rectangle(0, 0, imageWidth, imageHeight);
                }

                setMagnification(newMag);
                display.repaintAll2(); // this repaint includes this canvas's repaint, but updates the navigator without update_graphics
                display.updateInDatabase("srcRect");
        }

        /** The minimum amout of pixels allowed for width or height when zooming out. */
        static private final int MIN_DIMENSION = 10; // pixels

        /** Enable zooming out up to the point where the display becomes 10 pixels in width or height. */
        protected double getLowerZoomLevel2(final double currentMag) {
                // if it is 1/72 or lower, then:
                if (Math.abs(currentMag - 1/72.0) < 0.00000001 || currentMag < 1/72.0) { // lowest zoomLevel in ImageCanvas is 1/72.0
                        // find nearest power of two under currentMag
                        // start at level 7, which is 1/128
                        int level = 7;
                        double scale = currentMag;
                        while (scale * srcRect.width > MIN_DIMENSION && scale * srcRect.height > MIN_DIMENSION) {
                                scale = 1 / Math.pow(2, level);
                                // if not equal and actually smaller, break:
                                if (Math.abs(scale - currentMag) != 0.00000001 && scale < currentMag) break;
                                level++;
                        }
                        return scale;
                } else {
                        return ImageCanvas.getLowerZoomLevel(currentMag);
                }
        }
        protected double getHigherZoomLevel2(final double currentMag) {
                // if it is not 1/72 and its lower, then:
                if (Math.abs(currentMag - 1/72.0) > 0.00000001 && currentMag < 1/72.0) { // lowest zoomLevel in ImageCanvas is 1/72.0
                        // find nearest power of two above currentMag
                        // start at level 14, which is 0.00006103515625 (0.006 %)
                        int level = 14; // this value may be increased in the future
                        double scale = currentMag;
                        while (level >= 0) {
                                scale = 1 / Math.pow(2, level);
                                if (scale > currentMag) break;
                                level--;
                        }
                        return scale;
                } else {
                        return ImageCanvas.getHigherZoomLevel(currentMag);
                }
        }


        /*
         * // OBSOLETE: modified ij.gui.ImageCanvas directly
         public void mouseMoved(MouseEvent e) { if (IJ.getInstance()==null) return; int sx =
         * e.getX(); int sy = e.getY(); int ox = offScreenX(sx); int oy =
         * offScreenY(sy); flags = e.getModifiers(); setCursor(sx, sy, ox, oy);
         * IJ.setInputEvent(e); Roi roi = imp.getRoi(); if (roi!=null &&
         * (roi.getType()==Roi.POLYGON || roi.getType()==Roi.POLYLINE ||
         * roi.getType()==Roi.ANGLE) && roi.getState()==roi.CONSTRUCTING) {
         * PolygonRoi pRoi = (PolygonRoi)roi; pRoi.handleMouseMove(ox, oy); } else {
         * if (ox<imageWidth && oy<imageHeight) { //ImageWindow win =
         * imp.getWindow(); //if (win!=null) win.mouseMoved(ox, oy);
         * imp.mouseMoved(ox, oy); } else IJ.showStatus(""); } }
         */

        private Rectangle old_brush_box = null;

        private MouseMovedThread mouse_moved = new MouseMovedThread();

        private class MouseMovedThread extends Thread {
                private volatile MouseEvent me = null;
                MouseMovedThread() {
                        super("T2-mouseMoved");
                        setDaemon(true);
                        setPriority(Thread.NORM_PRIORITY);
                        start();
                }
                void dispatch(final MouseEvent me) {
                        //Utils.log2("before");
                        synchronized (this) {
                                //Utils.log2("in");
                                this.me = me;
                                notifyAll();
                        }
                }
                void quit() {
                        interrupt();
                        synchronized (this) { notifyAll(); }
                }
                @Override
                public void run() {
                        while (!isInterrupted()) {
                                MouseEvent me = this.me;
                                if (null != me) {
                                        try { mouseMoved(me); } catch (final Exception e) { IJError.print(e); }
                                }
                                // Wait only if the event has not changed
                                synchronized (this) {
                                        if (me == this.me) {
                                                // Release the pointer
                                                me = null;
                                                this.me = null;
                                                if (isInterrupted()) return;
                                                // Wait until there is a new event
                                                try { wait(); } catch (final Exception e) {}
                                        }
                                }
                        }
                }
                private void mouseMoved(final MouseEvent me) {
                        if (null == me) return;

                        if (input_disabled || display.getMode().isDragging()) return;

                        xMouse = (int)(me.getX() / magnification) + srcRect.x;
                        yMouse = (int)(me.getY() / magnification) + srcRect.y;
                        final Displayable active = display.getActive();

                        // only when no mouse buttons are down
                        final int flags = DisplayCanvas.super.flags;
                        if (0 == (flags & InputEvent.BUTTON1_MASK)
                        /* && 0 == (flags & InputEvent.BUTTON2_MASK) */ // this is the alt key down ..
                         && 0 == (flags & InputEvent.BUTTON3_MASK)
                        //if (me.getButton() == MouseEvent.NOBUTTON
                         && null != active && active.isVisible() && AreaContainer.class.isInstance(active)) {
                                final int tool = ProjectToolbar.getToolId();
                                Rectangle r = null;
                                if (ProjectToolbar.BRUSH == tool) {
                                        // repaint area where the brush circle is
                                        final int brushSize = ProjectToolbar.getBrushSize() +2; // +2 padding
                                        r = new Rectangle( xMouse - brushSize/2,
                                                           yMouse - brushSize/2,
                                                           brushSize+1,
                                                           brushSize+1 );
                                } else if (ProjectToolbar.PENCIL == tool || ProjectToolbar.WAND == tool) {
                                        // repaint area where the fast-marching box is
                                        r = new Rectangle( xMouse - Segmentation.fmp.width/2 - 2,
                                                           yMouse - Segmentation.fmp.height/2 - 2,
                                                           Segmentation.fmp.width + 4,
                                                           Segmentation.fmp.height + 4 );
                                }
                                if (null != r) {
                                        final Rectangle copy = (Rectangle)r.clone();
                                        if (null != old_brush_box) r.add(old_brush_box);
                                        old_brush_box = copy;
                                        repaint(r, 1); // padding because of painting rounding which would live dirty trails
                                }
                        }

                        if (me.isShiftDown()) {
                                // Print a comma-separated list of objects under the mouse pointer
                                final Layer layer = DisplayCanvas.this.display.getLayer();
                                final List<Displayable> al = getDisplayablesUnderMouse(me);
                                if (0 == al.size()) {
                                        Utils.showStatus("", false);
                                        return;
                                }
                                final StringBuilder sb = new StringBuilder();
                                final Project pr = layer.getProject();
                                for (final Displayable d : al) sb.append(pr.getShortMeaningfulTitle(d)).append(", ");
                                sb.setLength(sb.length()-2);
                                Utils.showStatus(sb.toString(), false);
                        } else {
                                // For very large images, the Patch.getPixel can take even half a minute
                                // to do the pixel grab operation.
                                //DisplayCanvas.super.mouseMoved(me);
                                // Instead, find out over what are we
                                final List<Displayable> under = getDisplayablesUnderMouse(me);
                                final Calibration cal = display.getLayerSet().getCalibration();
                                if (under.isEmpty()) {
                                        Utils.showStatus("x=" + (int)(xMouse * cal.pixelWidth) + " " + cal.getUnit()
                                                                                                         + ", y=" + (int)(yMouse * cal.pixelHeight) + " " + cal.getUnit());
                                        return;
                                }
                                final Displayable top = under.get(0);
                                String msg =
                                                        "x=" + (int)(xMouse * cal.pixelWidth) + " " + cal.getUnit()
                                                        + ", y=" + (int)(yMouse * cal.pixelHeight) + " " + cal.getUnit();
                                if (top.getClass() == Patch.class) {
                                        final Patch patch = (Patch)top;
                                        final int[] p = new int[4];
                                        BufferedImage offsc;
                                        synchronized (offscreen_lock) {
                                                offsc = offscreen;
                                        }
                                        if (null == offsc) return;
                                        try {
                                                final PixelGrabber pg = new PixelGrabber(offsc, me.getX(), me.getY(), 1, 1, p, 0, offsc.getWidth(null));
                                                pg.grabPixels();
                                        } catch (final InterruptedException ie) {
                                                IJError.print(ie);
                                                return;
                                        } catch (final Throwable t) {
                                                // The offscreen might have been flushed. Just ignore; pixel value will be reported next.
                                                return;
                                        }
                                        patch.approximateTransferPixel(p);
                                        msg += ", value=";
                                        switch (patch.getType()) {
                                                case ImagePlus.GRAY16:
                                                case ImagePlus.GRAY8:
                                                        msg += p[0];
                                                        break;
                                                case ImagePlus.GRAY32:
                                                        msg += Float.intBitsToFloat(p[0]);
                                                        break;
                                                case ImagePlus.COLOR_RGB:
                                                case ImagePlus.COLOR_256:
                                                        msg += "(" + p[0] + "," + p[1] + "," + p[2] + ")";
                                                        break;
                                        }
                                        msg += " [Patch #" + patch.getId() + "]";
                                } else {
                                        final Color c = top.getColor();
                                        msg += ", value=[" + c.getRed() + "," + c.getGreen() + "," + c.getBlue() + "] [" + Project.getName(top.getClass()) + " #" + top.getId() + "]";
                                }
                                Utils.showStatus(msg);
                        }
                }
        }

        /** See {@link DisplayCanvas#getDisplayablesUnderMouse(MouseEvent)}. */
        public List<Displayable> getDisplayablesUnderMouse() {
                return getDisplayablesUnderMouse(new MouseEvent(this, -1, 0, 0, xMouse, yMouse, 1, false));
        }

        /** Return the list of Displayable objects under the mouse,
         * sorted by proper stack order. */
        public List<Displayable> getDisplayablesUnderMouse(final MouseEvent me) {
                                final Layer layer = display.getLayer();
                                final int x_p = offScreenX(me.getX()),
                                          y_p = offScreenY(me.getY());
                                final ArrayList<Displayable> al = new ArrayList<Displayable>(layer.getParent().findZDisplayables(layer, x_p, y_p, true));
                                Collections.reverse(al);
                                final ArrayList<Displayable> al2 = new ArrayList<Displayable>(layer.find(x_p, y_p, true));
                                Collections.reverse(al2);
                                al.addAll(al2);
                                return al;
        }

        public boolean isDragging() {
                return display.getMode().isDragging();
        }

        @Override
        public void mouseMoved(final MouseEvent me) {
                super.flags = me.getModifiers();
                final int tool = Toolbar.getToolId();
                switch (tool) {
                case Toolbar.POLYLINE:
                case Toolbar.POLYGON:
                case Toolbar.ANGLE:
                        super.mouseMoved(me);
                        repaint();
                        return;
                }
                mouse_moved.dispatch(me);
        }

        /** Zoom in using the current mouse position, or the center if the mouse is out. */
        public void zoomIn() {
                if (xMouse < 0 || screenX(xMouse) > dstWidth || yMouse < 0 || screenY(yMouse) > dstHeight) {
                        zoomIn(dstWidth/2, dstHeight/2);
                } else {
                        zoomIn(screenX(xMouse), screenY(yMouse));
                }
        }

        /** Overriding to repaint the DisplayNavigator as well. */
        @Override
        public void zoomIn(final int x, final int y) {
                update_graphics = true; // update the offscreen images.
                zoomIn2(x, y);
        }

        /** Zoom out using the current mouse position, or the center if the mouse is out. */
        public void zoomOut() {
                if (xMouse < 0 || screenX(xMouse) > dstWidth || yMouse < 0 || screenY(yMouse) > dstHeight) {
                        zoomOut(dstWidth/2, dstHeight/2);
                } else zoomOut(screenX(xMouse), screenY(yMouse));
        }

        /** Overriding to repaint the DisplayNavigator as well. */
        @Override
        public void zoomOut(final int x, final int y) {
                update_graphics = true; // update the offscreen images.
                zoomOut2(x, y);
        }

        /** Center the srcRect around the given object(s) bounding box, zooming if necessary,
         *  so that the given r becomes a rectangle centered in the srcRect and zoomed out by a factor of 2. */
        public void showCentered(final Rectangle r) {
                // multiply bounding box dimensions by two
                r.x -= r.width / 2;
                r.y -= r.height / 2;
                r.width += r.width;
                r.height += r.height;
                // compute target magnification
                final double magn = getWidth() / (double)(r.width > r.height ? r.width : r.height);
                center(r, magn);
        }

        /** Show the given r as the srcRect (or as much of it as possible) at the given magnification. */
        public void center(final Rectangle r, double magn) {
                // bring bounds within limits of the layer and the canvas' drawing size
                final double lw = display.getLayer().getLayerWidth();
                final double lh = display.getLayer().getLayerHeight();
                final int cw = (int) (getWidth() / magn); // canvas dimensions in offscreen coords
                final int ch = (int) (getHeight() / magn);

                // 2nd attempt:
                // fit to canvas drawing size:
                r.y += (r.height - ch) / 2;
                r.width = cw;
                r.height = ch;
                // place within layer bounds
                if (r.x < 0) r.x = 0;
                if (r.y < 0) r.y = 0;
                if (r.width > lw) {
                        r.x = 0;
                        r.width = (int)lw;
                }
                if (r.height > lh) {
                        r.y = 0;
                        r.height = (int)lh;
                }
                if (r.x + r.width > lw) r.x = (int)(lw - cw);
                if (r.y + r.height > lh) r.y = (int)(lh - ch);
                // compute magn again, since the desired width may have changed:
                magn = getWidth() / (double)r.width;

                // set magnification and srcRect
                setup(magn, r);
                try { Thread.sleep(200); } catch (final Exception e) {} // swing ... waiting for the display.pack()
                update_graphics = true;
                RT.paint(null, update_graphics);
                display.updateInDatabase("srcRect");
                display.updateFrameTitle();
                display.getNavigator().repaint(false);
        }

        /** Repaint as much as the bounding box around the given Displayable. If the Displayable is null, the entire canvas is repainted, remaking the offscreen images. */
        public void repaint(final Displayable d) {
                repaint(d, 0);
        }

        /**
         * Repaint as much as the bounding box around the given Displayable plus the
         * extra padding. If the Displayable is null, the entire canvas is
         * repainted, remaking the offscreen images.
         */
        public void repaint(final Displayable displ, final int extra) {
                repaint(displ, extra, update_graphics);
        }
        public void repaint(final Displayable displ, final int extra, final boolean update_graphics) {
                if (null != displ) {
                        final Rectangle r = displ.getBoundingBox();
                        r.x = (int) ((r.x - srcRect.x) * magnification) - extra;
                        r.y = (int) ((r.y - srcRect.y) * magnification) - extra;
                        r.width = (int) Math.ceil(r.width * magnification) + extra + extra;
                        r.height = (int) Math.ceil(r.height * magnification) + extra + extra;
                        invalidateVolatile();
                        RT.paint(r, update_graphics);
                } else {
                        // everything
                        repaint(true);
                }
        }

        /**
         * Repaint the clip corresponding to the sum of all boundingboxes of
         * Displayable objects in the hashset.
         */
        // it is assumed that the linked objects are close to each other, otherwise
        // the clip rectangle grows enormously.
        public void repaint(final HashSet<Displayable> hs) {
                if (null == hs) return;
                Rectangle r = null;
                final Layer dl = display.getLayer();
                for (final Displayable d : hs) {
                        if (d.getLayer() == dl) {
                                if (null == r) r = d.getBoundingBox();
                                else r.add(d.getBoundingBox());
                        }
                }
                if (null != r) {
                        //repaint(r.x, r.y, r.width, r.height);
                        invalidateVolatile();
                        RT.paint(r, update_graphics);
                }
        }

        /**
         * Repaint the given offscreen Rectangle after transforming its data on the fly to the
         * srcRect and magnification of this DisplayCanvas. The Rectangle is not
         * modified.
         */
        public void repaint(final Rectangle r, final int extra) {
                invalidateVolatile();
                if (null == r) {
                        //Utils.log2("DisplayCanvas.repaint(Rectangle, int) warning: null r");
                        RT.paint(null, update_graphics);
                        return;
                }
                // repaint((int) ((r.x - srcRect.x) * magnification) - extra, (int) ((r.y - srcRect.y) * magnification) - extra, (int) Math .ceil(r.width * magnification) + extra + extra, (int) Math.ceil(r.height * magnification) + extra + extra);
                RT.paint(new Rectangle((int) ((r.x - srcRect.x) * magnification) - extra, (int) ((r.y - srcRect.y) * magnification) - extra, (int) Math.ceil(r.width * magnification) + extra + extra, (int) Math.ceil(r.height * magnification) + extra + extra), update_graphics);
        }

        /**
         * Repaint the given Rectangle after transforming its data on the fly to the
         * srcRect and magnification of this DisplayCanvas. The Rectangle is not
         * modified.
         * @param box The rectangle to repaint
         * @param extra The extra outbound padding to add to the rectangle
         * @param update_graphics Whether to recreate the offscreen images or not
         */
        public void repaint(final Rectangle box, final int extra, final boolean update_graphics) {
                this.update_graphics = update_graphics;
                repaint(box, extra);
        }

        /** Repaint everything, updating offscreen graphics if so specified. */
        public void repaint(final boolean update_graphics) {
                this.update_graphics = update_graphics | this.update_graphics;
                invalidateVolatile();
                RT.paint(null, this.update_graphics);
        }

        /** Overridden to multithread. This method is here basically to enable calls to the FakeImagePlus.draw from the HAND and other tools to repaint properly.*/
        @Override
        public void repaint() {
                //Utils.log2("issuing thread");
                invalidateVolatile();
                RT.paint(null, update_graphics);
        }

        /** Overridden to multithread. */
        /* // saved as unoveridden to make sure there are no infinite thread loops when calling super in buggy JVMs
        public void repaint(long ms, int x, int y, int width, int height) {
                RT.paint(new Rectangle(x, y, width, height), update_graphics);
        }
        */

        /** Overridden to multithread. */
        @Override
        public void repaint(final int x, final int y, final int width, final int height) {
                invalidateVolatile();
                RT.paint(new Rectangle(x, y, width, height), update_graphics);
        }

        public void setUpdateGraphics(final boolean b) {
                update_graphics = b;
        }

        /** Release offscreen images and stop threads. */
        public void flush() {
                // cleanup update graphics thread if any
                RT.quit();
                synchronized (offscreen_lock) {
                        if (null != offscreen) {
                                offscreen.flush();
                                offscreen = null;
                        }
                        update_graphics = true;
                        for (final BufferedImage bi : to_flush) bi.flush();
                        to_flush.clear();
                }
                mouse_moved.quit();
                try {
                        synchronized (this) { if (null != animator) animator.shutdownNow(); }
                        cancelAnimations();
                } catch (final Exception e) {}
                animator = null;
        }

        public void destroy() {
                flush();
                WindowManager.setTempCurrentImage(imp); // the FakeImagePlus
                WindowManager.removeWindow(fake_win); // the FakeImageWindow
        }

        public boolean applyTransform() {
                final boolean b = display.getMode().apply();
                if (b) {
                        display.setMode(new DefaultMode(display));
                        Display.repaint();
                }
                return b;
        }

        public boolean isTransforming() {
                // TODO this may have to change if modes start getting used for a task other than transformation.
                // Perhaps "isTransforming" will have to broaden its meaning to "isNotDefaultMode"
                return display.getMode().getClass() != DefaultMode.class;
        }

        public void cancelTransform() {
                display.getMode().cancel();
                display.setMode(new DefaultMode(display));
                repaint(true);
        }

        private int last_keyCode = KeyEvent.VK_ESCAPE;
        private boolean tagging = false;

        @Override
        public void keyPressed(final KeyEvent ke) {

                final Displayable active = display.getActive();

                if (null != freehandProfile
                        && ProjectToolbar.getToolId() == ProjectToolbar.PENCIL
                        && ke.getKeyCode() == KeyEvent.VK_ESCAPE
                        && null != freehandProfile)
                {
                        freehandProfile.abort();
                        ke.consume();
                        return;
                }

                final int keyCode = ke.getKeyCode();

                try {
                        // Enable tagging system for any alphanumeric key:
                        if (!input_disabled && null != active && active instanceof Tree<?> && ProjectToolbar.isDataEditTool(ProjectToolbar.getToolId())) {
                                if (tagging) {
                                        if (KeyEvent.VK_0 == keyCode && KeyEvent.VK_0 != last_keyCode) {
                                                // do nothing: keep tagging as true
                                        } else {
                                                // last step of tagging: a char after t or after t and a number (and the char itself can be a number)
                                                tagging = false;
                                        }
                                        active.keyPressed(ke);
                                        return;
                                } else if (KeyEvent.VK_T == keyCode) {
                                        tagging = true;
                                        active.keyPressed(ke);
                                        return;
                                }
                        }
                } finally {
                        last_keyCode = keyCode;
                }

                tagging = false;

                if (ke.isConsumed()) return;

                /*
                 * TODO screen editor ... TEMPORARY if (active instanceof DLabel) {
                 * active.keyPressed(ke); ke.consume(); return; }
                 */

                if (!zoom_and_pan) {
                        if (KeyEvent.VK_ESCAPE == keyCode) {
                                cancelAnimations();
                        }
                        return;
                }

                final int keyChar = ke.getKeyChar();

                boolean used = false;

                switch (keyChar) {
                case '+':
                case '=':
                        zoomIn();
                        used = true;
                        break;
                case '-':
                case '_':
                        zoomOut();
                        used = true;
                        break;
                default:
                        break;
                }


                if (used) {
                        ke.consume(); // otherwise ImageJ would use it!
                        return;
                }

                if (input_disabled) {
                        if (KeyEvent.VK_ESCAPE == keyCode) {
                                // cancel last job if any
                                if (Utils.checkYN("Really cancel job?")) {
                                        display.getProject().getLoader().quitJob(null);
                                        display.repairGUI();
                                }
                        }
                        ke.consume();
                        return; // only zoom is enabled, above
                }

                if (KeyEvent.VK_S == keyCode && 0 == ke.getModifiers() && display.getProject().getLoader().isAsynchronous()) {
                        display.getProject().getLoader().saveTask(display.getProject(), "Save");
                        ke.consume();
                        return;
                } else if (KeyEvent.VK_F == keyCode && Utils.isControlDown(ke)) {
                        Search.showWindow();
                        ke.consume();
                        return;
                }

                // if display is not read-only, check for other keys:
                switch (keyChar) {
                case '<':
                case ',': // select next Layer up
                        display.previousLayer(ke.getModifiers()); // repaints as well
                        ke.consume();
                        return;
                case '>':
                case '.': // select next Layer down
                        display.nextLayer(ke.getModifiers());
                        ke.consume();
                        return;
                }

                if (null == active && null != imp.getRoi() && KeyEvent.VK_A != keyCode) { // control+a and a roi should select under roi
                        IJ.getInstance().keyPressed(ke);
                        return;
                }

                // end here if display is read-only
                if (display.isReadOnly()) {
                        ke.consume();
                        display.repaintAll();
                        return;
                }

                if (KeyEvent.VK_ENTER == keyCode) {
                        if (isTransforming()) {
                                applyTransform();
                                ke.consume();
                                return;
                        } else {
                                IJ.getInstance().toFront();
                                ke.consume();
                                return;
                        }
                }

                // check preconditions (or the keys are meaningless). Allow 'enter' to
                // bring forward the ImageJ window, and 'v' to paste a patch.
                /*if (null == active && KeyEvent.VK_ENTER != keyCode && KeyEvent.VK_V != keyCode && KeyEvent) {
                        return;
                }*/

                final Layer layer = display.getLayer();

                final int mod = ke.getModifiers();

                switch (keyCode) {
                        case KeyEvent.VK_COMMA:
                        case 0xbc: // select next Layer up
                                display.nextLayer(ke.getModifiers());
                                break;
                        case KeyEvent.VK_PERIOD:
                        case 0xbe: // select next Layer down
                                display.previousLayer(ke.getModifiers());
                                break;
                        case KeyEvent.VK_Z:
                                // UNDO: shift+z or ctrl+z
                                if (0 == (mod ^ Event.SHIFT_MASK) || 0 == (mod ^ Utils.getControlModifier())) {
                                        Bureaucrat.createAndStart(new Worker.Task("Undo") { @Override
                                        public void exec() {
                                                if (isTransforming()) display.getMode().undoOneStep();
                                                else display.getLayerSet().undoOneStep();
                                                Display.repaint(display.getLayerSet());
                                        }}, display.getProject());
                                        ke.consume();
                                // REDO: alt+z or ctrl+shift+z
                                } else if (0 == (mod ^ Event.ALT_MASK) || 0 == (mod ^ (Event.SHIFT_MASK | Utils.getControlModifier())) ) {
                                        Bureaucrat.createAndStart(new Worker.Task("Redo") { @Override
                                        public void exec() {
                                                if (isTransforming()) display.getMode().redoOneStep();
                                                else display.getLayerSet().redoOneStep();
                                                Display.repaint(display.getLayerSet());
                                        }}, display.getProject());
                                        ke.consume();
                                }
                                // else, the 'z' command restores the image using ImageJ internal undo
                                break;
                        case KeyEvent.VK_T:
                                // Enable with any tool to the left of the PENCIL
                                if (null != active && !isTransforming() && ProjectToolbar.getToolId() < ProjectToolbar.PENCIL) {
                                        ProjectToolbar.setTool(ProjectToolbar.SELECT);
                                        if (0 == ke.getModifiers()) {
                                                display.setMode(new AffineTransformMode(display));
                                        } else if (Event.SHIFT_MASK == ke.getModifiers()) {
                                                for (final Displayable d : display.getSelection().getSelected()) {
                                                        if (d.isLinked()) {
                                                                Utils.showMessage("Can't enter manual non-linear transformation mode:\nat least one image is linked.");
                                                                return;
                                                        }
                                                }
                                                display.setMode(new NonLinearTransformMode(display));
                                        }
                                        ke.consume();
                                }
                                // else, let ImageJ grab the ROI into the Manager, if any
                                break;
                        case KeyEvent.VK_A:
                                if (0 == (ke.getModifiers() ^ Utils.getControlModifier())) {
                                        final Roi roi = getFakeImagePlus().getRoi();
                                        if (null != roi) display.getSelection().selectAll(roi, true);
                                        else display.getSelection().selectAllVisible();
                                        Display.repaint(display.getLayer(), display.getSelection().getBox(), 0);
                                        ke.consume();
                                        break; // INSIDE the 'if' block, so that it can bleed to the default block which forwards to active!
                                } else if (null != active) {
                                        active.keyPressed(ke);
                                        if (ke.isConsumed()) break;
                                        // TODO this is just a hack really. Should just fall back to default switch option.
                                        // The whole keyPressed method needs revision: should not break from it when not using the key.
                                }
                                break;
                        case KeyEvent.VK_ESCAPE: // cancel transformation
                                if (isTransforming()) cancelTransform();
                                else {
                                        display.select(null); // deselect
                                        // repaint out the brush if present
                                        if (ProjectToolbar.BRUSH == ProjectToolbar.getToolId()) {
                                                repaint(old_brush_box, 0);
                                        }
                                }
                                ke.consume();
                                break;
                        case KeyEvent.VK_SPACE:
                                if (0 == ke.getModifiers()) {
                                        if (null != active) {
                                                invalidateVolatile();
                                                if (Math.abs(active.getAlpha() - 0.5f) > 0.001f) active.setAlpha(0.5f);
                                                else active.setAlpha(1.0f);
                                                display.setTransparencySlider(active.getAlpha());
                                                Display.repaint();
                                                ke.consume();
                                        }
                                } else {
                                        // ;)
                                        final int kem = ke.getModifiers();
                                        if (0 != (kem & KeyEvent.SHIFT_MASK)
                                         && 0 != (kem & KeyEvent.ALT_MASK)
                                         && 0 != (kem & KeyEvent.CTRL_MASK)) {
                                                Utils.showMessage("A mathematician, like a painter or poet,\nis a maker of patterns.\nIf his patterns are more permanent than theirs,\nit is because they are made with ideas\n \nG. H. Hardy.");
                                                ke.consume();
                                         }
                                }
                                break;
                        case KeyEvent.VK_S:
                                if (ke.isAltDown()) {
                                        snapping = true;
                                        ke.consume();
                                } else if (dragging) {
                                        // ignore improper 's' that open ImageJ's save dialog (linux problem ... in macosx, a single dialog opens with lots of 'ssss...' in the text field)
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_H:
                                handleHide(ke);
                                ke.consume();
                                break;
                        case KeyEvent.VK_J:
                                if (!display.getSelection().isEmpty()) {
                                        display.adjustMinAndMaxGUI();
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_F1:
                        case KeyEvent.VK_F2:
                        case KeyEvent.VK_F3:
                        case KeyEvent.VK_F4:
                        case KeyEvent.VK_F5:
                        case KeyEvent.VK_F6:
                        case KeyEvent.VK_F7:
                        case KeyEvent.VK_F8:
                        case KeyEvent.VK_F9:
                        case KeyEvent.VK_F10:
                        case KeyEvent.VK_F11:
                        case KeyEvent.VK_F12:
                                ProjectToolbar.keyPressed(ke);
                                ke.consume();
                                break;
                        case KeyEvent.VK_M:
                                if (0 == ke.getModifiers() && ProjectToolbar.getToolId() == ProjectToolbar.SELECT) {
                                        display.getSelection().measure();
                                        ke.consume();
                                }
                                break;
                }

                switch (keyChar) {
                        case ':':
                        case ';':
                                if (null != active && active instanceof ZDisplayable) {
                                        if (null != display.getProject().getProjectTree().tryAddNewConnector(active, true)) {
                                                ProjectToolbar.setTool(ProjectToolbar.PEN);
                                        }
                                        ke.consume();
                                }
                                break;
                }

                if (ke.isConsumed()) return;

                if (null != active) {
                        if (display.getMode().getClass() == DefaultMode.class) {
                                active.keyPressed(ke);
                        }
                        if (ke.isConsumed()) return;
                }

                // Else:
                switch (keyCode) {
                        case KeyEvent.VK_G:
                                if (browseToNodeLayer(ke.isShiftDown())) {
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_I:
                                if (ke.isAltDown()) {
                                        if (ke.isShiftDown()) display.importImage();
                                        else display.importNextImage();
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_PAGE_UP: // as in Inkscape
                                if (null != active) {
                                        update_graphics = true;
                                        layer.getParent().addUndoMoveStep(active);
                                        layer.getParent().move(LayerSet.UP, active);
                                        layer.getParent().addUndoMoveStep(active);
                                        Display.repaint(layer, active, 5);
                                        Display.updatePanelIndex(layer, active);
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_PAGE_DOWN: // as in Inkscape
                                if (null != active) {
                                        update_graphics = true;
                                        layer.getParent().addUndoMoveStep(active);
                                        layer.getParent().move(LayerSet.DOWN, active);
                                        layer.getParent().addUndoMoveStep(active);
                                        Display.repaint(layer, active, 5);
                                        Display.updatePanelIndex(layer, active);
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_HOME: // as in Inkscape
                                if (null != active) {
                                        update_graphics = true;
                                        layer.getParent().addUndoMoveStep(active);
                                        layer.getParent().move(LayerSet.TOP, active);
                                        layer.getParent().addUndoMoveStep(active);
                                        Display.repaint(layer, active, 5);
                                        Display.updatePanelIndex(layer, active);
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_END: // as in Inkscape
                                if (null != active) {
                                        update_graphics = true;
                                        layer.getParent().addUndoMoveStep(active);
                                        layer.getParent().move(LayerSet.BOTTOM, active);
                                        layer.getParent().addUndoMoveStep(active);
                                        Display.repaint(layer, active, 5);
                                        Display.updatePanelIndex(layer, active);
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_V:
                                if (0 == ke.getModifiers()) {
                                        if (null == active || active.getClass() == Patch.class) {
                                                // paste a new image
                                                final ImagePlus clipboard = ImagePlus.getClipboard();
                                                if (null != clipboard) {
                                                        final ImagePlus imp = new ImagePlus(clipboard.getTitle() + "_" + System.currentTimeMillis(), clipboard.getProcessor().crop());
                                                        final Object info = clipboard.getProperty("Info");
                                                        if (null != info) imp.setProperty("Info", (String)info);
                                                        final double x = srcRect.x + srcRect.width/2 - imp.getWidth()/2;
                                                        final double y = srcRect.y + srcRect.height/2 - imp.getHeight()/2;
                                                        // save the image somewhere:
                                                        final Patch pa = display.getProject().getLoader().addNewImage(imp, x, y);
                                                        display.getLayer().add(pa);
                                                        ke.consume();
                                                } // TODO there isn't much ImageJ integration in the pasting. Can't paste to a selected image, for example.
                                        } else {
                                                // Each type may know how to paste data from the copy buffer into itself:
                                                active.keyPressed(ke);
                                                ke.consume();
                                        }
                                }
                                break;
                        case KeyEvent.VK_P:
                                if (0 == ke.getModifiers()) {
                                        display.getLayerSet().color_cues = !display.getLayerSet().color_cues;
                                        Display.repaint(display.getLayerSet());
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_F:
                                if (0 == (ke.getModifiers() ^ KeyEvent.SHIFT_MASK)) {
                                        // toggle visibility of tags
                                        display.getLayerSet().paint_tags = !display.getLayerSet().paint_tags;
                                        Display.repaint();
                                        ke.consume();
                                } else if (0 == (ke.getModifiers() ^ KeyEvent.ALT_MASK)) {
                                        // toggle visibility of edge arrows
                                        display.getLayerSet().paint_arrows = !display.getLayerSet().paint_arrows;
                                        Display.repaint();
                                        ke.consume();
                                } else if (0 == ke.getModifiers()) {
                                        // toggle visibility of edge confidence boxes
                                        display.getLayerSet().paint_edge_confidence_boxes = !display.getLayerSet().paint_edge_confidence_boxes;
                                        Display.repaint();
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_DELETE:
                                if (0 == ke.getModifiers()) {
                                        display.getSelection().deleteAll();
                                }
                                break;
                        case KeyEvent.VK_B:
                                if (0 == ke.getModifiers() && null != active && active.getClass() == Profile.class) {
                                        display.duplicateLinkAndSendTo(active, 0, active.getLayer().getParent().previous(layer));
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_N:
                                if (0 == ke.getModifiers() && null != active && active.getClass() == Profile.class) {
                                        display.duplicateLinkAndSendTo(active, 1, active.getLayer().getParent().next(layer));
                                        ke.consume();
                                }
                                break;
                        case KeyEvent.VK_1:
                        case KeyEvent.VK_2:
                        case KeyEvent.VK_3:
                        case KeyEvent.VK_4:
                        case KeyEvent.VK_5:
                        case KeyEvent.VK_6:
                        case KeyEvent.VK_7:
                        case KeyEvent.VK_8:
                        case KeyEvent.VK_9:
                                // run a plugin, if any
                                if (null != Utils.launchTPlugIn(ke, "Display", display.getProject(), display.getActive())) {
                                        ke.consume();
                                        break;
                                }
                }

                if ( !(keyCode == KeyEvent.VK_UNDEFINED || keyChar == KeyEvent.CHAR_UNDEFINED) && !ke.isConsumed() && null != active && active instanceof Patch) {
                        // TODO should allow forwarding for all, not just Patch
                        // forward to ImageJ for a final try
                        IJ.getInstance().keyPressed(ke);
                        repaint(active, 5);
                        ke.consume();
                }
                //Utils.log2("keyCode, keyChar: " + keyCode + ", " + keyChar + " ref: " + KeyEvent.VK_UNDEFINED + ", " + KeyEvent.CHAR_UNDEFINED);
        }

        @Override
        public void keyTyped(final KeyEvent ke) {}

        @Override
        public void keyReleased(final KeyEvent ke) {}

        public void zoomToFit() {
                final double magw = (double) getWidth() / imageWidth;
                final double magh = (double) getHeight() / imageHeight;
                this.magnification = magw < magh ? magw : magh;
                this.srcRect.setRect(0, 0, imageWidth, imageHeight);
                setMagnification(magnification);
                display.updateInDatabase("srcRect"); // includes magnification
        }


        public void setReceivesInput(final boolean b) {
                this.input_disabled = !b;
        }

        public boolean isInputEnabled() {
                return !input_disabled;
        }

        /** CAREFUL: the ImageProcessor of the returned ImagePlus is fake, that is, a 4x4 byte array; but the dimensions that it returns are those of the host LayerSet. Used to retrieve ROIs for example.*/
        public ImagePlus getFakeImagePlus() {
                return this.imp;
        }

        /** Key/Mouse bindings like:
         * - ij.gui.StackWindow: wheel to scroll slices (in this case Layers)
         * - Inkscape: control+wheel to zoom (apple+wheel in macosx, since control+wheel zooms desktop)
         */
        @Override
        public void mouseWheelMoved(final MouseWheelEvent mwe) {
                if (dragging) return; // prevent unexpected mouse wheel movements
                final int modifiers = mwe.getModifiers();
                final int rotation = mwe.getWheelRotation();
                final int tool = ProjectToolbar.getToolId();
                if (0 != (modifiers & Utils.getControlModifier())) {
                        if (!zoom_and_pan) return;
                        // scroll zoom under pointer
                        int x = mwe.getX();
                        int y = mwe.getY();
                        if (x < 0 || y < 0 || x >= getWidth() || y >= getHeight()) {
                                x = getWidth()/2;
                                y = getHeight()/2;
                        }

                        // Current mouse point in world coords
                        final double xx = x/magnification + srcRect.x;
                        final double yy = y/magnification + srcRect.y;
                        // Delta of view, in screen pixels:
                        final int px_inc;
                        if ( 0 != (modifiers & MouseWheelEvent.SHIFT_MASK)) {
                                if (0 != (modifiers & MouseWheelEvent.ALT_MASK)) px_inc = 1;
                                else px_inc = 5;
                        } else px_inc = 20;
                        final double inc = px_inc/magnification;

                        final Rectangle r = new Rectangle();

                        if (rotation > 0) {
                                // zoom out
                                r.width = srcRect.width + (int)(inc+0.5);
                                r.height = srcRect.height + (int)(inc+0.5);
                                r.x = (int)(xx - ((xx - srcRect.x)/srcRect.width) * r.width + 0.5);
                                r.y = (int)(yy - ((yy - srcRect.y)/srcRect.height) * r.height + 0.5);
                                // check boundaries
                                if (r.width * magnification < getWidth()
                                 || r.height * magnification < getHeight()) {
                                        // Can't zoom at point: would chage field of view's flow or would have to shift the canvas position!
                                        Utils.showStatus("To zoom more, use -/+ keys");
                                        return;
                                }
                        } else {
                                //zoom in
                                r.width = srcRect.width - (int)(inc+0.5);
                                r.height = srcRect.height - (int)(inc+0.5);
                                if (r.width < 1 || r.height < 1) {
                                        return;
                                }
                                r.x = (int)(xx - ((xx - srcRect.x)/srcRect.width) * r.width + 0.5);
                                r.y = (int)(yy - ((yy - srcRect.y)/srcRect.height) * r.height + 0.5);
                        }
                        final double newMag = magnification * (srcRect.width / (double)r.width);
                        // correct floating-point-induced erroneous drift: the int-precision offscreen point under the mouse shoud remain the same
                        r.x -= (int)((x/newMag + r.x) - xx);
                        r.y -= (int)((y/newMag + r.y) - yy);

                        // adjust bounds
                        int w = (int) Math.round(dstWidth / newMag);
                        if (w * newMag < dstWidth) w++;
                        if (w > imageWidth) w = imageWidth;
                        int h = (int) Math.round(dstHeight / newMag);
                        if (h * newMag < dstHeight) h++;
                        if (h > imageHeight) h = imageHeight;
                        if (r.x < 0) r.x = 0;
                        if (r.y < 0) r.y = 0;
                        if (r.x + w > imageWidth) r.x = imageWidth - w;
                        if (r.y + h > imageHeight) r.y = imageHeight - h; //imageWidth and imageHeight are the LayerSet's width,height, ie. the world's 2D dimensions.

                        // set!
                        this.setMagnification(newMag);
                        this.setSrcRect(r.x, r.y, w, h);
                        display.repaintAll2();

                } else if (0 == (modifiers ^ InputEvent.SHIFT_MASK) && null != display.getActive() && ProjectToolbar.PEN != tool && AreaContainer.class.isInstance(display.getActive())) {
                        final int sign = rotation > 0 ? 1 : -1;
                        if (ProjectToolbar.BRUSH == tool) {
                                final int brushSize_old = ProjectToolbar.getBrushSize();
                                // resize brush for AreaList/AreaTree painting
                                int brushSize = ProjectToolbar.setBrushSize((int)(5 * sign / magnification)); // the getWheelRotation provides the sign
                                if (brushSize_old > brushSize) brushSize = brushSize_old; // for repainting purposes alone
                                int extra = (int)(10 / magnification);
                                if (extra < 2) extra = 2;
                                extra += 4; // for good measure
                                this.repaint(new Rectangle((int)(mwe.getX() / magnification) + srcRect.x - brushSize/2 - extra, (int)(mwe.getY() / magnification) + srcRect.y - brushSize/2 - extra, brushSize+extra, brushSize+extra), 0);
                        } else if (ProjectToolbar.PENCIL == tool || ProjectToolbar.WAND == tool) {
                                // resize area to consider for fast-marching
                                int w = Segmentation.fmp.width;
                                int h = Segmentation.fmp.height;
                                Segmentation.fmp.resizeArea(sign, magnification);
                                w = Math.max(w, Segmentation.fmp.width);
                                h = Math.max(h, Segmentation.fmp.height);
                                this.repaint(new Rectangle((int)(mwe.getX() / magnification) + srcRect.x - w/2 + 2,
                                                           (int)(mwe.getY() / magnification) + srcRect.y - h/2 + 2,
                                                           w + 4, h + 4), 0);
                        }
                } else if (0 == modifiers) {
                        // scroll layers
                        if (rotation > 0) display.nextLayer(modifiers);
                        else display.previousLayer(modifiers);
                } else if (null != display.getActive()) {
                        // forward to active
                        display.getActive().mouseWheelMoved(mwe);
                }
        }

        protected class RepaintProperties implements AbstractOffscreenThread.RepaintProperties {
                final private Layer layer;
                final private List<Layer> layers;
                final private int g_width;
                final private int g_height;
                final private Rectangle srcRect;
                final private double magnification;
                final private Displayable active;
                final private int c_alphas;
                final private Rectangle clipRect;
                final private int mode;
                final private HashMap<Color,Layer> hm;
                final private ArrayList<LayerPanel> blending_list;
                final private GraphicsSource graphics_source;

                RepaintProperties(final Rectangle clipRect, final Layer layer, final List<Layer> layers, final int g_width, final int g_height, final Rectangle srcRect, final double magnification, final Displayable active, final int c_alphas, final GraphicsSource graphics_source) {
                        this.clipRect = clipRect;
                        this.layer = layer;
                        this.layers = layers;
                        this.g_width = g_width;
                        this.g_height = g_height;
                        this.srcRect = srcRect;
                        this.magnification = magnification;
                        this.active = active;
                        this.c_alphas = c_alphas;

                        // query the display for repainting mode
                        this.hm = new HashMap<Color,Layer>();
                        this.blending_list = new ArrayList<LayerPanel>();
                        this.mode = display.getPaintMode(hm, blending_list);
                        this.graphics_source = graphics_source;
                }
        }

        private final class OffscreenThread extends AbstractOffscreenThread {

                OffscreenThread() {
                        super("T2-Canvas-Offscreen");
                }

                @Override
                public void paint() {
                        final Layer active_layer;
                        final List<Layer> layers;
                        final int g_width;
                        final int g_height;
                        final Rectangle srcRect;
                        final double magnification;
                        final Displayable active;
                        final int c_alphas;
                        final Rectangle clipRect;
                        final Loader loader;
                        final HashMap<Color,Layer> hm;
                        final ArrayList<LayerPanel> blending_list;
                        final int mode;
                        final GraphicsSource graphics_source;

                        synchronized (this) {
                                final DisplayCanvas.RepaintProperties rp = (DisplayCanvas.RepaintProperties) this.rp;
                                active_layer = rp.layer;
                                layers = rp.layers;
                                g_width = rp.g_width;
                                g_height = rp.g_height;
                                srcRect = rp.srcRect;
                                magnification = rp.magnification;
                                active = rp.active;
                                c_alphas = rp.c_alphas;
                                clipRect = rp.clipRect;
                                loader = active_layer.getProject().getLoader();
                                mode = rp.mode;
                                hm = rp.hm;
                                blending_list = rp.blending_list;
                                graphics_source = rp.graphics_source;
                        }

                        BufferedImage target = null;

                        final ArrayList<Displayable> al_top = new ArrayList<Displayable>();

                        // Check if the image is cached
                        Screenshot sc = null;
                        try {
                                if (display.getMode().getClass() == DefaultMode.class) {
                                        sc = active_layer.getParent().getScreenshot(new ScreenshotProperties(active_layer, srcRect, magnification, g_width, g_height, c_alphas, graphics_source));
                                        if (null != sc) {
                                                //Utils.log2("Using cached screenshot " + sc + " with srcRect " + sc.srcRect);
                                                target = (BufferedImage) loader.getCachedAWT(sc.sid, 0);
                                                if (null == target) active_layer.getParent().removeFromOffscreens(sc); // the image was thrown out of the cache
                                                else if ( (sc.al_top.size() > 0 && sc.al_top.get(0) != display.getActive())
                                                       || (0 == sc.al_top.size() && null != display.getActive()) ) {
                                                        // Can't accept: different active object
                                                        Utils.log2("rejecting: different active object");
                                                        target = null;
                                                } else {
                                                        al_top.addAll(sc.al_top);
                                                        display.applyFilters(target);
                                                }
                                        }
                                }
                        } catch (final Throwable t) {
                                IJError.print(t);
                        }

                        //Utils.log2("Found target " + target + "\n  with al_top.size() = " + al_top.size());

                        if (null == target) {
                                target = paintOffscreen(active_layer, layers, g_width, g_height, srcRect, magnification, active, c_alphas, clipRect, loader, hm, blending_list, mode, graphics_source, active_layer.getParent().prepaint, al_top, true);
                                // Store it:
                                /* CAN'T, may have prePaint in it
                                if (null != sc && display.getProject().getProperty("look_ahead_cache", 0) > 0) {
                                        sc.assoc(target);
                                        layer.getParent().storeScreenshot(sc);
                                }
                                */
                        }

                        synchronized (offscreen_lock) {
                                // only on success:
                                if (null != offscreen) to_flush.add(offscreen);
                                offscreen = target;
                                update_graphics = false;
                                DisplayCanvas.this.al_top = al_top;
                        }
                        // Outside, otherwise could deadlock
                        invalidateVolatile();

                        // Send repaint event, without offscreen graphics
                        RT.paint(clipRect, false);
                }
        }

        /** Looks into the layer and its LayerSet and finds out what needs to be painted, putting it into the three lists.
         *  @return the index of the first non-image object. */
        private final int gatherDisplayables(final Layer layer, final List<Layer> layers, final Rectangle srcRect, final Displayable active, final ArrayList<Displayable> al_paint, final ArrayList<Displayable> al_top, final boolean preload_patches) {
                layer.getParent().checkBuckets();
                layer.checkBuckets();
                final Iterator<Displayable> ital = layer.find(srcRect, true).iterator();
                final Collection<Displayable> zdal;
                final LayerSet layer_set = layer.getParent();
                // Which layers to color cue, if any?
                if (layer_set.color_cues) {
                        final Collection<Displayable> atlayer = layer_set.roughlyFindZDisplayables(layer, srcRect, true);
                        final Set<Displayable> others = new HashSet<Displayable>();
                        for (final Layer la : layers) {
                                if (la == layer) continue;
                                others.addAll(layer_set.roughlyFindZDisplayables(la, srcRect, true));
                        }
                        others.removeAll(atlayer);
                        zdal = new ArrayList<Displayable>(others); // in whatever order, to paint under
                        zdal.addAll(atlayer); // in proper stack-index order
                } else {
                        zdal = layer_set.roughlyFindZDisplayables(layer, srcRect, true);
                }
                final Iterator<Displayable> itzd = zdal.iterator();

                // Assumes the Layer has its objects in order:
                // 1 - Patches
                // 2 - Profiles, Balls
                // 3 - Pipes and ZDisplayables (from the parent LayerSet)
                // 4 - DLabels

                Displayable tmp = null;
                boolean top = false;
                final ArrayList<Patch> al_patches = preload_patches ? new ArrayList<Patch>() : null;

                int first_non_patch = 0;

                while (ital.hasNext()) {
                        final Displayable d = ital.next();
                        final Class<?> c = d.getClass();
                        if (DLabel.class == c || LayerSet.class == c) {
                                tmp = d; // since ital.next() has moved forward already
                                break;
                        }
                        if (Patch.class == c) {
                                al_paint.add(d);
                                if (preload_patches) al_patches.add((Patch)d);
                        } else {
                                if (!top && d == active) top = true; // no Patch on al_top ever
                                if (top) al_top.add(d); // so active is added to al_top, if it's not a Patch
                                else al_paint.add(d);
                        }
                        first_non_patch += 1;
                }

                // preload concurrently as many as possible
                if (preload_patches) Loader.preload(al_patches, magnification, false); // must be false; a 'true' would incur in an infinite loop.

                // paint the ZDisplayables here, before the labels and LayerSets, if any
                while (itzd.hasNext()) {
                        final Displayable zd = itzd.next();
                        if (zd == active) top = true;
                        if (top) al_top.add(zd);
                        else al_paint.add(zd);
                }
                // paint LayerSet and DLabel objects!
                if (null != tmp) {
                        if (tmp == active) top = true;
                        if (top) al_top.add(tmp);
                        else al_paint.add(tmp);
                }
                while (ital.hasNext()) {
                        final Displayable d = ital.next();
                        if (d == active) top = true;
                        if (top) al_top.add(d);
                        else al_paint.add(d);
                }

                return first_non_patch;
        }

        @Deprecated
        public BufferedImage paintOffscreen(final Layer active_layer, final int g_width, final int g_height,
                        final Rectangle srcRect, final double magnification, final Displayable active,
                        final int c_alphas, final Rectangle clipRect, final Loader loader, final HashMap<Color,Layer> hm,
                        final ArrayList<LayerPanel> blending_list, final int mode, final GraphicsSource graphics_source,
                        final boolean prepaint, final ArrayList<Displayable> al_top) {
                return paintOffscreen(active_layer, active_layer.getParent().getColorCueLayerRange(active_layer), g_width, g_height, srcRect, magnification, active,
                                                c_alphas, clipRect, loader, hm, blending_list, mode, graphics_source,
                                                prepaint, al_top, false);
        }

        /** This method uses data only from the arguments, and changes none.
         *  Will fill @param al_top with proper Displayable objects, or none when none are selected. */
        public BufferedImage paintOffscreen(final Layer active_layer, final List<Layer> layers, final int g_width, final int g_height,
                        final Rectangle srcRect, final double magnification, final Displayable active,
                        final int c_alphas, final Rectangle clipRect, final Loader loader, final HashMap<Color,Layer> hm,
                        final ArrayList<LayerPanel> blending_list, final int mode, final GraphicsSource graphics_source,
                        final boolean prepaint, final ArrayList<Displayable> al_top, final boolean preload) {

                final ArrayList<Displayable> al_paint = new ArrayList<Displayable>();
                final int first_non_patch = gatherDisplayables(active_layer, layers, srcRect, active, al_paint, al_top, preload);

                return paintOffscreen(active_layer, layers, al_paint, active, g_width, g_height, c_alphas, loader, hm, blending_list, mode, graphics_source, prepaint, first_non_patch);
        }

        public BufferedImage paintOffscreen(final Layer active_layer, final List<Layer> layers, final ArrayList<Displayable> al_paint, final Displayable active, final int g_width, final int g_height, final int c_alphas, final Loader loader, final HashMap<Color,Layer> hm, final ArrayList<LayerPanel> blending_list, final int mode, final GraphicsSource graphics_source, final boolean prepaint, int first_non_patch) {
                try {
                        if (0 == g_width || 0 == g_height) return null;
                        // ALMOST, but not always perfect //if (null != clipRect) g.setClip(clipRect);

                        // prepare the canvas for the srcRect and magnification
                        final AffineTransform atc = new AffineTransform();
                        atc.scale(magnification, magnification);
                        atc.translate(-srcRect.x, -srcRect.y);

                        // the non-srcRect areas, in offscreen coords
                        final Rectangle r1 = new Rectangle(srcRect.x + srcRect.width, srcRect.y, (int)(g_width / magnification) - srcRect.width, (int)(g_height / magnification));
                        final Rectangle r2 = new Rectangle(srcRect.x, srcRect.y + srcRect.height, srcRect.width, (int)(g_height / magnification) - srcRect.height);

                        // create new graphics
                        try {
                                display.getProject().getLoader().releaseToFit(g_width * g_height * 10);
                        } catch (final Exception e) {} // when closing, asynch state may throw for a null loader.

                        final BufferedImage target = getGraphicsConfiguration().createCompatibleImage(g_width, g_height, Transparency.TRANSLUCENT); // creates a BufferedImage.TYPE_INT_ARGB image in my T60p ATI FireGL laptop
                        //Utils.log2("offscreen acceleration priority: " + target.getAccelerationPriority());
                        final Graphics2D g = target.createGraphics();

                        g.setTransform(atc); //at_original);

                        //setRenderingHints(g);
                        // always a stroke of 1.0, regardless of magnification; the stroke below corrects for that
                        g.setStroke(stroke);



                        // Testing: removed Area.subtract, now need to fill in background
                        g.setColor(Color.black);
                        g.fillRect(0, 0, g_width - r1.x, g_height - r2.y);


                        // paint:
                        //  1 - background
                        //  2 - images and anything else not on al_top
                        //  3 - non-srcRect areas

                        //Utils.log2("offscreen painting: " + al_paint.size());

                        // filter paintables
                        final Collection<? extends Paintable> paintables = graphics_source.asPaintable(al_paint);

                        // adjust:
                        first_non_patch = paintables.size() - (al_paint.size() - first_non_patch);

                        // Determine painting mode
                        if (Display.REPAINT_SINGLE_LAYER == mode) {
                                if (display.isLiveFilteringEnabled()) {
                                        paintWithFiltering(g, al_paint, paintables, first_non_patch, g_width, g_height, active, c_alphas, active_layer, layers, true);
                                } else {
                                        // Direct painting mode, with prePaint abilities
                                        int i = 0;
                                        for (final Paintable d : paintables) {
                                                if (i == first_non_patch) {
                                                        //Object antialias = g.getRenderingHint(RenderingHints.KEY_ANTIALIASING);
                                                        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,  RenderingHints.VALUE_ANTIALIAS_ON); // to smooth edges of the images
                                                        //Object text_antialias = g.getRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING);
                                                        g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
                                                        //Object render_quality = g.getRenderingHint(RenderingHints.KEY_RENDERING);
                                                        g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
                                                }
                                                if (prepaint) d.prePaint(g, srcRect, magnification, d == active, c_alphas, active_layer, layers);
                                                else d.paint(g, srcRect, magnification, d == active, c_alphas, active_layer, layers);
                                                i++;
                                        }
                                }
                        } else if (Display.REPAINT_MULTI_LAYER == mode) {
                                // paint first the current layer Patches only (to set the background)
                                // With prePaint capabilities:
                                if (display.isLiveFilteringEnabled()) {
                                        paintWithFiltering(g, al_paint, paintables, first_non_patch, g_width, g_height, active, c_alphas, active_layer, layers, false);
                                } else {
                                        int i = 0;
                                        if (prepaint) {
                                                for (final Paintable d : paintables) {
                                                        if (first_non_patch == i) break;
                                                        d.prePaint(g, srcRect, magnification, d == active, c_alphas, active_layer, layers);
                                                        i++;
                                                }
                                        } else {
                                                for (final Paintable d : paintables) {
                                                        if (first_non_patch == i) break;
                                                        d.paint(g, srcRect, magnification, d == active, c_alphas, active_layer, layers);
                                                        i++;
                                                }
                                        }
                                }

                                // then blend on top the ImageData of the others, in reverse Z order and using the alpha of the LayerPanel
                                final Composite original = g.getComposite();
                                // reset
                                g.setTransform(new AffineTransform());
                                // Paint what:
                                final Set<Class<?>> included = display.classes_to_multipaint;
                                for (final ListIterator<LayerPanel> it = blending_list.listIterator(blending_list.size()); it.hasPrevious(); ) {
                                        final LayerPanel lp = it.previous();
                                        if (lp.layer == active_layer) continue;
                                        active_layer.getProject().getLoader().releaseToFit(g_width * g_height * 4 + 1024);
                                        final BufferedImage bi = getGraphicsConfiguration().createCompatibleImage(g_width, g_height, Transparency.TRANSLUCENT);
                                        final Graphics2D gb = bi.createGraphics();
                                        gb.setTransform(atc);
                                        for (final Displayable d : lp.layer.find(srcRect, true)) {
                                                if (included.contains(d.getClass()))
                                                        d.paint(gb, srcRect, magnification, false, c_alphas, lp.layer, layers); // not prePaint! We want direct painting, even if potentially slow
                                        }
                                        // Repeating loop ... the human compiler at work, just because one cannot lazily concatenate both sequences:
                                        for (final Displayable d : lp.layer.getParent().roughlyFindZDisplayables(lp.layer, srcRect, true)) {
                                                if (included.contains(d.getClass()))
                                                                d.paint(gb, srcRect, magnification, false, c_alphas, lp.layer, layers); // not prePaint! We want direct painting, even if potentially slow
                                        }
                                        try {
                                                g.setComposite(Displayable.getComposite(display.getLayerCompositeMode(lp.layer), lp.getAlpha()));
                                                g.drawImage(display.applyFilters(bi), 0, 0, null);
                                        } catch (final Throwable t) {
                                                Utils.log("Could not use composite mode for layer overlays! Your graphics card may not support it.");
                                                g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, lp.getAlpha()));
                                                g.drawImage(bi, 0, 0, null);
                                                IJError.print(t);
                                        }
                                        bi.flush();
                                }
                                // restore
                                g.setComposite(original);
                                g.setTransform(atc);

                                // then paint the non-Patch objects of the current layer

                                //Object antialias = g.getRenderingHint(RenderingHints.KEY_ANTIALIASING);
                                g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,  RenderingHints.VALUE_ANTIALIAS_ON); // to smooth edges of the images
                                //Object text_antialias = g.getRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING);
                                g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
                                //Object render_quality = g.getRenderingHint(RenderingHints.KEY_RENDERING);
                                g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);

                                // TODO this loop should be reading from the paintable_patches and paintables, since their length/order *could* have changed
                                // For the current layer:
                                for (int i = first_non_patch; i < al_paint.size(); i++) {
                                        final Displayable d = al_paint.get(i);
                                        d.paint(g, srcRect, magnification, d == active, c_alphas, active_layer, layers);
                                }
                        } else if(Display.REPAINT_RGB_LAYER == mode) {
                                // TODO rewrite to avoid calling the list twice
                                final Collection<? extends Paintable> paintable_patches = graphics_source.asPaintable(al_paint);
                                //
                                final HashMap<Color,byte[]> channels = new HashMap<Color,byte[]>();
                                hm.put(Color.green, active_layer);
                                for (final Map.Entry<Color,Layer> e : hm.entrySet()) {
                                        final BufferedImage bi = new BufferedImage(g_width, g_height, BufferedImage.TYPE_BYTE_GRAY); //INDEXED, Loader.GRAY_LUT);
                                        final Graphics2D gb = bi.createGraphics();
                                        gb.setTransform(atc);
                                        final Layer la = e.getValue();
                                        final ArrayList<Paintable> list = new ArrayList<Paintable>();
                                        if (la == active_layer) {
                                                if (Color.green != e.getKey()) continue; // don't paint current layer in two channels
                                                list.addAll(paintable_patches);
                                        } else {
                                                list.addAll(la.find(Patch.class, srcRect, true));
                                        }
                                        list.addAll(la.getParent().getZDisplayables(ImageData.class, true)); // Stack.class and perhaps others
                                        for (final Paintable d : list) {
                                                d.paint(gb, srcRect, magnification, false, c_alphas, la, layers);
                                        }
                                        channels.put(e.getKey(), (byte[])new ByteProcessor(bi).getPixels());
                                }
                                final byte[] red, green, blue;
                                green = channels.get(Color.green);
                                if (null == channels.get(Color.red)) red = new byte[green.length];
                                else red = channels.get(Color.red);
                                if (null == channels.get(Color.blue)) blue = new byte[green.length];
                                else blue = channels.get(Color.blue);
                                final int[] pix = new int[green.length];
                                for (int i=0; i<green.length; i++) {
                                        pix[i] = ((red[i] & 0xff) << 16) + ((green[i] & 0xff) << 8) + (blue[i] & 0xff);
                                }
                                // undo transform, is intended for Displayable objects
                                g.setTransform(new AffineTransform());
                                final ColorProcessor cp = new ColorProcessor(g_width, g_height, pix);
                                if (display.invert_colors) cp.invert();
                                display.applyFilters(cp);
                                final Image img = cp.createImage();
                                g.drawImage(img, 0, 0, null);
                                img.flush();
                                // reset
                                g.setTransform(atc);

                                // then paint the non-Image objects of the current layer
                                //Object antialias = g.getRenderingHint(RenderingHints.KEY_ANTIALIASING);
                                g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,  RenderingHints.VALUE_ANTIALIAS_ON); // to smooth edges of the images
                                //Object text_antialias = g.getRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING);
                                g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
                                //Object render_quality = g.getRenderingHint(RenderingHints.KEY_RENDERING);
                                g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);

                                for (final Displayable d : al_paint) {
                                        if (ImageData.class.isInstance(d)) continue;
                                        d.paint(g, srcRect, magnification, d == active, c_alphas, active_layer, layers);
                                }
                                // TODO having each object type in a key/list<type> table would be so much easier and likely performant.
                        }

                        // finally, paint non-srcRect areas
                        if (r1.width > 0 || r1.height > 0 || r2.width > 0 || r2.height > 0) {
                                g.setColor(Color.gray);
                                g.setClip(r1);
                                g.fill(r1);
                                g.setClip(r2);
                                g.fill(r2);
                        }

                        return target;
                } catch (final OutOfMemoryError oome) {
                        // so OutOfMemoryError won't generate locks
                        IJError.print(oome);
                } catch (final Exception e) {
                        IJError.print(e);
                }
                return null;
        }

        private final void paintWithFiltering(final Graphics2D g, final ArrayList<Displayable> al_paint,
                                                                                  final Collection<? extends Paintable> paintables,
                                                                                  final int first_non_patch,
                                                                                  final int g_width, final int g_height,
                                                                                  final Displayable active, final int c_alphas,
                                                                                  final Layer layer, final List<Layer> layers, final boolean paint_non_images) {
                // Determine the type of the image: if any Patch is of type COLOR_RGB or COLOR_256, use RGB
                int type = BufferedImage.TYPE_BYTE_GRAY;
                search: for (final Displayable d : al_paint) {
                        if (d.getClass() == Patch.class) {
                                switch (((Patch)d).getType()) {
                                        case ImagePlus.COLOR_256:
                                        case ImagePlus.COLOR_RGB:
                                                type = BufferedImage.TYPE_INT_ARGB;
                                                break search;
                                }
                        }
                }

                // Paint all patches to an image
                final BufferedImage bi = new BufferedImage(g_width, g_height, type);
                final Graphics2D gpre = bi.createGraphics();
                gpre.setTransform(atc);
                int i = 0;
                for (final Paintable p : paintables) {
                        if (i == first_non_patch) break;
                        p.paint(gpre, srcRect, magnification, p == active, c_alphas, layer, layers);
                        i++;
                }
                gpre.dispose();
                final ImagePlus imp = new ImagePlus("filtered", type == BufferedImage.TYPE_BYTE_GRAY ? new ByteProcessor(bi) : new ColorProcessor(bi));
                bi.flush();

                display.applyFilters(imp);

                // Paint the filtered image
                final AffineTransform aff = g.getTransform();
                g.setTransform(new AffineTransform()); // reset
                g.drawImage(imp.getProcessor().createImage(), 0, 0, null);
                // Paint the remaining elements if any
                if (paint_non_images && first_non_patch != paintables.size()) {
                        g.setTransform(aff); // restore srcRect and magnification
                        g.setRenderingHint(RenderingHints.KEY_ANTIALIASING,  RenderingHints.VALUE_ANTIALIAS_ON); // to smooth edges of the images
                        g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
                        g.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
                        i = 0;
                        for (final Paintable p : paintables) {
                                if (i < first_non_patch) {
                                        i++;
                                        continue;
                                }
                                p.paint(g, srcRect, magnification, p == active, c_alphas, layer, layers);
                                i++;
                        }
                }

        }

        // added here to prevent flickering, but doesn't help. All it does is avoid a call to imp.redraw()
        @Override
        protected void scroll(final int sx, final int sy) {
                final int ox = xSrcStart + (int)(sx/magnification);  //convert to offscreen coordinates
                final int oy = ySrcStart + (int)(sy/magnification);
                int newx = xSrcStart + (xMouseStart-ox);
                int newy = ySrcStart + (yMouseStart-oy);
                if (newx<0) newx = 0;
                if (newy<0) newy = 0;
                if ((newx+srcRect.width)>imageWidth) newx = imageWidth-srcRect.width;
                if ((newy+srcRect.height)>imageHeight) newy = imageHeight-srcRect.height;
                srcRect.x = newx;
                srcRect.y = newy;
                display.getMode().srcRectUpdated(srcRect, magnification);
        }

        private void handleHide(final KeyEvent ke) {
                if (ke.isAltDown() && !ke.isShiftDown()) {
                        // show hidden
                        Display.updateCheckboxes(display.getLayer().getParent().setAllVisible(false), DisplayablePanel.VISIBILITY_STATE);
                        //Display.repaint(display.getLayer());
                        Display.update(display.getLayer());
                        ke.consume();
                        return;
                }
                if (ke.isShiftDown()) {
                        // hide deselected
                        display.hideDeselected(ke.isAltDown());
                        ke.consume();
                        return;
                }
                // else, hide selected
                display.getSelection().setVisible(false);
                Display.update(display.getLayer());
                ke.consume();
        }

        DisplayCanvas.Screenshot createScreenshot(final Layer layer) {
                return new Screenshot(layer);
        }

        protected class ScreenshotProperties {
                final Layer layer;
                final Rectangle srcRect;
                final double magnification;
                final int g_width, g_height, c_alphas;
                final GraphicsSource graphics_source;
                final ArrayList<LayerPanel> blending_list;
                final HashMap<Color,Layer> hm;
                final int mode;
                ScreenshotProperties(final Layer layer, final Rectangle srcRect, final double magnification, final int g_width, final int g_height, final int c_alphas, final GraphicsSource graphics_source) {
                        this.srcRect = new Rectangle(srcRect);
                        this.magnification = magnification;
                        this.layer = layer;
                        this.blending_list = new ArrayList<LayerPanel>();
                        this.hm = new HashMap<Color,Layer>();
                        this.mode = display.getPaintMode(hm, blending_list);
                        this.g_width = g_width;
                        this.g_height = g_height;
                        this.graphics_source = graphics_source;
                        this.c_alphas = c_alphas;
                        final Layer current_layer = display.getLayer();
                        if (Display.REPAINT_RGB_LAYER == mode) {
                                final Layer red = hm.get(Color.red);
                                final Layer blue = hm.get(Color.blue);
                                if (null != red || null != blue) {
                                        final LayerSet ls = layer.getParent();
                                        final int i_layer = ls.indexOf(layer);
                                        final int i_current = ls.indexOf(current_layer);
                                        if (null != red) {
                                                final int i_red = ls.indexOf(red);
                                                final Layer l = red.getParent().getLayer(i_red + i_current - i_layer);
                                                if (null != l) {
                                                        hm.put(Color.red, l);
                                                } else {
                                                        hm.remove(Color.red);
                                                }
                                        }
                                        if (null != blue) {
                                                final int i_blue = ls.indexOf(blue);
                                                final Layer l = blue.getParent().getLayer(i_blue + i_current - i_layer);
                                                if (null != l) {
                                                        hm.put(Color.blue, l);
                                                } else {
                                                        hm.remove(Color.blue);
                                                }
                                        }
                                }
                        }
                }
                @Override
                public final boolean equals(final Object o) {
                        final ScreenshotProperties s = (ScreenshotProperties)o;
                        return s.layer == this.layer
                          && s.magnification == this.magnification
                          && s.srcRect.x == this.srcRect.x && s.srcRect.y == this.srcRect.y
                          && s.srcRect.width == this.srcRect.width && s.srcRect.height == this.srcRect.height
                          && s.mode == this.mode
                          && s.c_alphas == this.c_alphas
                          && Utils.equalContent(s.blending_list, this.blending_list)
                          && Utils.equalContent(s.hm, this.hm);
                }
                @Override
                public int hashCode() { return 0; } //$%^&$#@!
        }

        public class Screenshot {
                final Layer layer;
                long sid = Long.MIN_VALUE;
                long born = 0;
                final ArrayList<Displayable> al_top = new ArrayList<Displayable>();
                final ScreenshotProperties props;

                Screenshot(final Layer layer) {
                        this(layer, DisplayCanvas.this.srcRect, DisplayCanvas.this.magnification, DisplayCanvas.this.getWidth(), DisplayCanvas.this.getHeight(), DisplayCanvas.this.display.getDisplayChannelAlphas(), DisplayCanvas.this.display.getMode().getGraphicsSource());
                }

                Screenshot(final Layer layer, final Rectangle srcRect, final double magnification, final int g_width, final int g_height, final int c_alphas, final GraphicsSource graphics_source) {
                        this.layer = layer;
                        this.props = new ScreenshotProperties(layer, srcRect, magnification, g_width, g_height, c_alphas, graphics_source);
                }

                public long init() {
                        this.born = System.currentTimeMillis();
                        this.sid = layer.getProject().getLoader().getNextTempId();
                        return this.sid;
                }
                /** Associate @param img to this, with a new sid. */
                public long assoc(final BufferedImage img) {
                        init();
                        if (null != img) layer.getProject().getLoader().cacheAWT(this.sid, img);
                        return this.sid;
                }
                public void createImage() {
                        final BufferedImage img = paintOffscreen(layer, layer.getParent().getColorCueLayerRange(layer),  props.g_width, props.g_height, props.srcRect, props.magnification,
                                                  display.getActive(), props.c_alphas, null, layer.getProject().getLoader(),
                                                  props.hm, props.blending_list, props.mode, props.graphics_source, false, al_top, false);
                        layer.getProject().getLoader().cacheAWT(sid, img);
                }
                public void flush() {
                        layer.getProject().getLoader().decacheAWT(sid);
                }
        }

        private boolean browseToNodeLayer(final boolean is_shift_down) {
                // find visible instances of Tree that are currently painting in the canvas
                try {
                        final Layer active_layer = display.getLayer();
                        final Point po = getCursorLoc(); // in offscreen coords
                        for (final ZDisplayable zd : display.getLayerSet().getDisplayableList()) {
                                if (!zd.isVisible()) continue;
                                if (!(zd instanceof Tree<?>)) continue;
                                final Tree<?> t = (Tree<?>)zd;
                                final Layer la = t.toClosestPaintedNode(active_layer, po.x, po.y, magnification);
                                if (null == la) continue;
                                // Else:
                                display.toLayer(la);
                                if (!is_shift_down) display.getSelection().clear();
                                display.getSelection().add(t);
                                switch (ProjectToolbar.getToolId()) {
                                        case ProjectToolbar.PEN:
                                        case ProjectToolbar.BRUSH:
                                                break;
                                        default:
                                                ProjectToolbar.setTool(ProjectToolbar.PEN);
                                                break;
                                }
                                return true;
                        }
                } catch (final Exception e) {
                        Utils.log2("Oops: " + e);
                }
                return false;
        }

        /** Smoothly move the canvas from x0,y0,layer0 to x1,y1,layer1 */
        protected void animateBrowsing(final int dx, final int dy) {
                // check preconditions
                final float mag = (float)this.magnification;
                final Rectangle startSrcRect = (Rectangle)this.srcRect.clone();
                // The motion will be displaced by some screen pixels at every time step.
                final Vector2f v = new Vector2f(dx, dy);
                final float sqdist_to_travel = v.lengthSquared();
                v.normalize();
                v.scale(20/mag);
                final Point2f cp = new Point2f(0, 0); // the current deltas
                //
                final ScheduledFuture<?>[] sf = new ScheduledFuture[1];
                sf[0] = animate(new Runnable() {
                        @Override
                        public void run() {
                                cp.add(v);
                                //Utils.log2("advanced by x,y = " + cp.x + ", " + cp.y);
                                int x, y;
                                if (v.lengthSquared() >= sqdist_to_travel) {
                                        // set target position
                                        x = startSrcRect.x + dx;
                                        y = startSrcRect.y + dy;
                                        // quit animation
                                        cancelAnimation(sf[0]);
                                } else {
                                        // set position
                                        x = startSrcRect.x + (int)(cp.x);
                                        y = startSrcRect.y + (int)(cp.y);
                                }
                                setSrcRect(x, y, startSrcRect.width, startSrcRect.height);
                                display.repaintAll2();
                        }
                }, 0, 50, TimeUnit.MILLISECONDS);
        }

        /** Smoothly move the canvas from its current position until the given rectangle is included within the srcRect.
         * If the given rectangle is larger than the srcRect, it will refuse to work (for now). */
        public boolean animateBrowsing(final Rectangle target_, final Layer target_layer) {
                // Crop target to world's 2D dimensions
                final Area a = new Area(target_);
                a.intersect(new Area(display.getLayerSet().get2DBounds()));
                final Rectangle target = a.getBounds();
                if (0 == target.width || 0 == target.height) {
                        return false;
                }
                // animate at all?
                if (this.srcRect.contains(target) && target_layer == display.getLayer()) {
                        // So: don't animate, but at least highlight the target
                        playHighlight(target);
                        return false;
                }

                // The motion will be displaced by some screen pixels at every time step.
                final int ox = srcRect.x + srcRect.width/2;
                final int oy = srcRect.y + srcRect.height/2;
                final int tx = target.x + target.width/2;
                final int ty = target.y + target.height/2;
                final Vector2f v = new Vector2f(tx - ox, ty - oy);
                v.normalize();
                v.scale(20/(float)magnification);


                // The layer range
                final Layer start_layer = display.getLayer();
                /*
                int ithis = display.getLayerSet().indexOf(start_layer);
                int itarget = display.getLayerSet().indexOf(target_layer);
                final java.util.List<Layer> layers = display.getLayerSet().getLayers(ithis, itarget);
                */
                final Calibration cal = display.getLayerSet().getCalibrationCopy();
                final double pixelWidth = cal.pixelWidth;
                final double pixelHeight = cal.pixelHeight;

                //final double dist_to_travel = Math.sqrt(Math.pow((tx - ox)*pixelWidth, 2) + Math.pow((ty - oy)*pixelHeight, 2)
                //                                              + Math.pow((start_layer.getZ() - target_layer.getZ()) * pixelWidth, 2));

                // vector in calibrated coords between origin and target
                final Vector3d g = new Vector3d((tx - ox)*pixelWidth, (ty - oy)*pixelHeight, (target_layer.getZ() - start_layer.getZ())*pixelWidth);

                final ScheduledFuture<?>[] sf = new ScheduledFuture[1];
                sf[0] = animate(new Runnable() {
                        @Override
                        public void run() {
                                if (DisplayCanvas.this.srcRect.contains(target)) {
                                        // reached destination
                                        if (display.getLayer() != target_layer) display.toLayer(target_layer);
                                        playHighlight(target);
                                        cancelAnimation(sf[0]);
                                } else {
                                        setSrcRect(srcRect.x + (int)v.x, srcRect.y + (int)v.y, srcRect.width, srcRect.height);
                                        // which layer?
                                        if (start_layer != target_layer) {
                                                final int cx = srcRect.x + srcRect.width/2;
                                                final int cy = srcRect.y + srcRect.height/2;
                                                final double dist = Math.sqrt(Math.pow((cx - ox)*pixelWidth, 2) + Math.pow((cy - oy)*pixelHeight, 2)
                                                                        + Math.pow((display.getLayer().getZ() - start_layer.getZ()) * pixelWidth, 2));

                                                final Vector3d gg = new Vector3d(g);
                                                gg.normalize();
                                                gg.scale((float)dist);
                                                final Layer la = display.getLayerSet().getNearestLayer(start_layer.getZ() + gg.z/pixelWidth);
                                                if (la != display.getLayer()) {
                                                        display.toLayer(la);
                                                }
                                        }
                                        display.repaintAll2();
                                }
                        }
                }, 0, 50, TimeUnit.MILLISECONDS);
                return true;
        }

        private ScheduledExecutorService animator = null;
        private boolean zoom_and_pan = true;
        private final Vector<ScheduledFuture<?>> sfs = new Vector<ScheduledFuture<?>>();

        private void cancelAnimations() {
                if (sfs.isEmpty()) return;
                Vector<ScheduledFuture<?>> sfs;
                synchronized (this.sfs) { sfs = new Vector<ScheduledFuture<?>>(this.sfs); }
                for (final ScheduledFuture<?> sf : sfs) {
                        sf.cancel(true);
                }
                this.sfs.clear();
                try {
                        // wait
                        Thread.sleep(150);
                } catch (final InterruptedException ie) {}
                // Re-enable input, in case the watcher task is canceled as well:
                // (It's necessary since there isn't any easy way to tell the scheduler to execute a code block when it cancels its tasks).
                restoreUserInput();
        }
        private void cancelAnimation(final ScheduledFuture<?> sf) {
                sfs.remove(sf);
                sf.cancel(true);
                restoreUserInput();
        }

        private void restoreUserInput() {
                zoom_and_pan = true;
                display.getProject().setReceivesInput(true);
        }

        private ScheduledFuture<?> animate(final Runnable run, final long initialDelay, final long delay, final TimeUnit units) {
                initAnimator();
                // Cancel any animations currently running
                cancelAnimations();
                // Disable user input
                display.getProject().setReceivesInput(false);
                zoom_and_pan = false;
                // Create tasks to run periodically: a task and a watcher task
                final ScheduledFuture<?>[] sf = new ScheduledFuture[2];
                sf[0] = animator.scheduleWithFixedDelay(run, initialDelay, delay, units);
                sf[1] = animator.scheduleWithFixedDelay(new Runnable() {
                        @Override
                        public void run() {
                                if (sf[0].isCancelled()) {
                                        // Enable user input
                                        zoom_and_pan = true;
                                        display.getProject().setReceivesInput(true);
                                        // cancel yourself
                                        sf[1].cancel(true);
                                }
                        }
                }, 100, 700, TimeUnit.MILLISECONDS);
                // Store task for future cancelation
                sfs.add(sf[0]);
                // but not the watcher task, which must finish on its own after the main task finishes.
                return sf[0];
        }

        /** Draw a dotted circle centered on the given Rectangle. */
        private final class Highlighter {
                Ellipse2D.Float elf;
                final Stroke stroke = new BasicStroke(2, BasicStroke.CAP_BUTT, BasicStroke.JOIN_MITER, 3, new float[]{4,4,4,4}, 0);
                final float dec;
                final Rectangle target;
                Highlighter(final Rectangle target) {
                        this.target = target;
                        elf = new Ellipse2D.Float(target.x, target.y, target.width, target.height);
                        display.getLayerSet().getOverlay().add(elf, Color.yellow, stroke, true);
                        dec = (float)((Math.max(target.width, target.height)*magnification / 10)/magnification);
                }
                boolean next() {
                        invalidateVolatile();
                        repaint(target, 5, false);
                        // setup next iteration
                        display.getLayerSet().getOverlay().remove(elf);
                        final Ellipse2D.Float elf2 = (Ellipse2D.Float) elf.clone();
                        elf2.x += dec;
                        elf2.y += dec;
                        elf2.width -= (dec+dec);
                        elf2.height -= (dec+dec);
                        if (elf2.width > 1 || elf2.height > 1) {
                                elf = elf2;
                                display.getLayerSet().getOverlay().add(elf, Color.yellow, stroke, true);
                                return true;
                        } else {
                                display.getLayerSet().getOverlay().remove(elf);
                                return false;
                        }
                }
                void cleanup() {
                        display.getLayerSet().getOverlay().remove(elf);
                }
        }

        private interface Animation extends Runnable {}

        private ScheduledFuture<?> playHighlight(final Rectangle target) {
                initAnimator();
                final Highlighter highlight = new Highlighter(target);
                final ScheduledFuture<?>[] sf = (ScheduledFuture<?>[])new ScheduledFuture[2];
                sf[0] = animator.scheduleWithFixedDelay(new Animation() {
                        @Override
                        public void run() {
                                if (!highlight.next()) {
                                        cancelAnimation(sf[0]);
                                        highlight.cleanup();
                                }
                        }
                }, 10, 100, TimeUnit.MILLISECONDS);
                sf[1] = animator.scheduleWithFixedDelay(new Animation() {
                        @Override
                        public void run() {
                                if (sf[0].isCancelled()) {
                                        highlight.cleanup();
                                        sf[1].cancel(true); // itself
                                }
                        }
                }, 50, 100, TimeUnit.MILLISECONDS);
                sfs.add(sf[0]);
                return sf[0];
        }

        synchronized private void initAnimator() {
                if (null == animator) animator = Executors.newScheduledThreadPool(2);
        }
}