src/edu/mit/ezyang/gravity/j3d/utils/picking/behaviors/SmartPickTranslateBehavior.java

   1 package edu.mit.ezyang.gravity.j3d.utils.picking.behaviors;
   2
   3 import edu.mit.ezyang.gravity.j3d.utils.behaviors.mouse.SmartMouseTranslate;
   4 import edu.mit.ezyang.gravity.j3d.*;
   5 import com.sun.j3d.utils.picking.behaviors.*;
   6 import com.sun.j3d.utils.picking.*;
   7 import com.sun.j3d.utils.behaviors.mouse.*;
   8 import javax.media.j3d.*;
   9
  10 /**
  11  * Reimplemented PickTranslateBehavior, but uses SmartMouseTranslate, which
  12  * has been customized to take into account rotations relative to the surface
  13  * display. Modifications are solely in constructor and new setRotateTransformGroup
  14  * method.
  15  * @warning Convenience constructor with pick mode parameter not implemented.
  16  * @author Edward Z. Yang <ezyang@mit.edu>
  17  */
  18 public class SmartPickTranslateBehavior extends PickMouseBehavior implements MouseBehaviorCallback {
  19
  20     private SmartMouseTranslate translate;
  21     private PickingCallback callback = null;
  22     private TransformGroup currentTG;
  23
  24     /**
  25      * Propagates rotation transform group to SmartMouseTranslate in order
  26      * to provide appropriate information to transform.
  27      * @note We only support one rotation transform group; this should be
  28      *       enough for people with shallow object graphs.
  29      * @param group TransformGroup with rotation we need to adjust to
  30      */
  31     public void setRotateTransformGroup(TransformGroup group) {
  32         translate.setRotateTransformGroup(group);
  33     }
  34
  35     /**
  36      * Creates a pick/translate behavior that waits for user mouse events for
  37      * the scene graph.
  38      * @param root   Root of your scene graph.
  39      * @param canvas Java 3D drawing canvas.
  40      * @param bounds Bounds of your scene.
  41      **/
  42     public SmartPickTranslateBehavior(BranchGroup root, Canvas3D canvas, Bounds bounds) {
  43         super(canvas, root, bounds);
  44         translate = new SmartMouseTranslate(MouseBehavior.MANUAL_WAKEUP);
  45         translate.setTransformGroup(currGrp);
  46         currGrp.addChild(translate);
  47         translate.setSchedulingBounds(bounds);
  48         this.setSchedulingBounds(bounds);
  49     }
  50
  51     // below code is copied verbatim from com.sun.j3d.utils.picking.behaviors
  52
  53     /**
  54      * Update the scene to manipulate any nodes. This is not meant to be
  55      * called by users. Behavior automatically calls this. You can call
  56      * this only if you know what you are doing.
  57      *
  58      * @param xpos Current mouse X pos.
  59      * @param ypos Current mouse Y pos.
  60      **/
  61     public void updateScene(int xpos, int ypos) {
  62         TransformGroup tg = null;
  63
  64         if (!mevent.isAltDown() && mevent.isMetaDown()) {
  65
  66             pickCanvas.setShapeLocation(xpos, ypos);
  67             PickResult pr = pickCanvas.pickClosest();
  68             if ((pr != null) &&
  69                     ((tg = (TransformGroup) pr.getNode(PickResult.TRANSFORM_GROUP)) != null) &&
  70                     (tg.getCapability(TransformGroup.ALLOW_TRANSFORM_READ)) &&
  71                     (tg.getCapability(TransformGroup.ALLOW_TRANSFORM_WRITE))) {
  72
  73                 translate.setTransformGroup(tg);
  74                 translate.wakeup();
  75                 currentTG = tg;
  76             // Need to clean up Issue 123 --- Chien
  77             // freePickResult(pr);
  78             } else if (callback != null) {
  79                 callback.transformChanged(PickingCallback.NO_PICK, null);
  80             }
  81         }
  82
  83     }
  84
  85     /**
  86      * Callback method from MouseTranslate
  87      * This is used when the Picking callback is enabled
  88      */
  89     public void transformChanged(int type, Transform3D transform) {
  90         callback.transformChanged(PickingCallback.TRANSLATE, currentTG);
  91     }
  92
  93     /**
  94      * Register the class @param callback to be called each
  95      * time the picked object moves
  96      */
  97     public void setupCallback(PickingCallback callback) {
  98         this.callback = callback;
  99         if (callback == null) {
 100             translate.setupCallback(null);
 101         } else {
 102             translate.setupCallback(this);
 103         }
 104     }
 105 }