libs/gtkmm2ext/pixfader.cc

   1 /*
   2     Copyright (C) 2006 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify
   5     it under the terms of the GNU General Public License as published by
   6     the Free Software Foundation; either version 2 of the License, or
   7     (at your option) any later version.
   8
   9     This program is distributed in the hope that it will be useful,
  10     but WITHOUT ANY WARRANTY; without even the implied warranty of
  11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12     GNU General Public License for more details.
  13
  14     You should have received a copy of the GNU General Public License
  15     along with this program; if not, write to the Free Software
  16     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18     $Id: fastmeter.h 570 2006-06-07 21:21:21Z sampo $
  19 */
  20
  21
  22 #include <iostream>
  23 #include "gtkmm2ext/pixfader.h"
  24 #include "gtkmm2ext/keyboard.h"
  25 #include "gtkmm2ext/rgb_macros.h"
  26
  27 using namespace Gtkmm2ext;
  28 using namespace Gtk;
  29 using namespace std;
  30
  31 int PixFader::fine_scale_modifier = Keyboard::PrimaryModifier;
  32 int PixFader::extra_fine_scale_modifier = Keyboard::SecondaryModifier;
  33
  34 PixFader::PixFader (Glib::RefPtr<Gdk::Pixbuf> belt, Gtk::Adjustment& adj, int orientation, int fader_length)
  35
  36         : adjustment (adj),
  37           pixbuf (belt),
  38           _orien(orientation)
  39 {
  40         Cairo::Format format;
  41
  42         dragging = false;
  43         default_value = adjustment.get_value();
  44         last_drawn = -1;
  45
  46         view.x = 0;
  47         view.y = 0;
  48
  49         if (orientation == VERT) {
  50                 view.width = girth = pixbuf->get_width();
  51         } else {
  52                 view.height = girth = pixbuf->get_height();
  53         }
  54
  55         set_fader_length (fader_length);
  56
  57         add_events (Gdk::BUTTON_PRESS_MASK|Gdk::BUTTON_RELEASE_MASK|Gdk::POINTER_MOTION_MASK|Gdk::SCROLL_MASK|Gdk::ENTER_NOTIFY_MASK|Gdk::LEAVE_NOTIFY_MASK);
  58
  59         adjustment.signal_value_changed().connect (mem_fun (*this, &PixFader::adjustment_changed));
  60         adjustment.signal_changed().connect (mem_fun (*this, &PixFader::adjustment_changed));
  61
  62         if (pixbuf->get_has_alpha()) {
  63                 format = Cairo::FORMAT_ARGB32;
  64         } else {
  65                 format = Cairo::FORMAT_RGB24;
  66         }
  67         belt_surface = Cairo::ImageSurface::create  (format, pixbuf->get_width(), pixbuf->get_height());
  68         belt_context = Cairo::Context::create (belt_surface);
  69         Gdk::Cairo::set_source_pixbuf (belt_context, pixbuf, 0.0, 0.0);
  70         belt_context->paint();
  71
  72         left_r = 0;
  73         left_g = 0;
  74         left_b = 0;
  75
  76         right_r = 0;
  77         right_g = 0;
  78         right_b = 0;
  79 }
  80
  81 PixFader::~PixFader ()
  82 {
  83 }
  84
  85 void
  86 PixFader::set_border_colors (uint32_t left, uint32_t right)
  87 {
  88         int r, g, b;
  89         UINT_TO_RGB(left, &r, &g, &b);
  90         left_r = r/255.0;
  91         left_g = g/255.0;
  92         left_b = b/255.0;
  93         UINT_TO_RGB(right, &r, &g, &b);
  94         right_r = r/255.0;
  95         right_g = g/255.0;
  96         right_b = b/255.0;
  97 }
  98
  99 bool
 100 PixFader::on_expose_event (GdkEventExpose* ev)
 101 {
 102         Cairo::RefPtr<Cairo::Context> context = get_window()->create_cairo_context();
 103         int srcx, srcy;
 104         int const ds = display_span ();
 105         int offset_into_pixbuf = (int) floor (span / ((float) span / ds));
 106
 107         /* account for fader lengths that are shorter than the fader pixbuf */
 108         if (_orien == VERT) {
 109                 offset_into_pixbuf += pixbuf->get_height() / 2 - view.height;
 110         } else {
 111                 offset_into_pixbuf += pixbuf->get_width() / 2 - view.width;
 112         }
 113
 114         context->rectangle (ev->area.x, ev->area.y, ev->area.width, ev->area.height);
 115         context->clip ();
 116
 117         if (_orien == VERT) {
 118                 srcx = 0;
 119                 srcy = offset_into_pixbuf;
 120         } else {
 121                 srcx = offset_into_pixbuf;
 122                 srcy = 0;
 123         }
 124
 125         /* fader */
 126
 127         context->save();
 128         context->set_source (belt_surface, -srcx, -srcy);
 129         context->rectangle (0, 0, get_width(), get_height());
 130         context->clip ();
 131         context->paint();
 132         context->restore();
 133
 134         /* bounding box lines (2 colors for nicer visuals) */
 135
 136         /* top and left side */
 137
 138         context->set_line_width (1);
 139         context->set_source_rgb (left_r, left_g, left_b);
 140         context->move_to (view.width - 1, 0); /* upper right */
 141         context->line_to (0, 0);              /* upper left */
 142         context->line_to (0, view.height - 1);/* lower left */
 143         context->stroke ();
 144
 145         /* bottom & right side */
 146
 147         context->set_line_width (1);
 148         context->set_source_rgb (right_r, right_g, right_b);
 149         context->move_to (0, view.height - 0.5); /* lower left */
 150         context->line_to (view.width - 0.5, view.height - 0.5); /* lower right */
 151         context->line_to (view.width - 0.5, 0); /* upper right */
 152         context->stroke ();
 153
 154         /* always draw the unity-position line */
 155
 156
 157         if (_orien == VERT) {
 158                 context->set_line_width (1);
 159                 context->set_source_rgb (0.0, 1.0, 0.0);
 160                 context->move_to (1, unity_loc);
 161                 context->line_to (girth, unity_loc);
 162                 context->stroke ();
 163         } else {
 164                 context->set_line_width (1);
 165                 context->set_source_rgb (0.0, 1.0, 0.0);
 166                 context->move_to (unity_loc, 1);
 167                 context->line_to (unity_loc, girth - 1);
 168                 context->stroke ();
 169         }
 170
 171         last_drawn = ds;
 172
 173         return true;
 174 }
 175
 176 void
 177 PixFader::on_size_request (GtkRequisition* req)
 178 {
 179         req->width = view.width;
 180         req->height = view.height;
 181 }
 182
 183 bool
 184 PixFader::on_button_press_event (GdkEventButton* ev)
 185 {
 186         if (ev->type != GDK_BUTTON_PRESS) {
 187                 return false;
 188         }
 189
 190         if (ev->button != 1 && ev->button != 2) {
 191                 return false;
 192         }
 193
 194         add_modal_grab ();
 195         grab_loc = (_orien == VERT) ? ev->y : ev->x;
 196         grab_start = (_orien == VERT) ? ev->y : ev->x;
 197         grab_window = ev->window;
 198         dragging = true;
 199
 200         if (ev->button == 2) {
 201                 set_adjustment_from_event (ev);
 202         }
 203
 204         return true;
 205 }
 206
 207 bool
 208 PixFader::on_button_release_event (GdkEventButton* ev)
 209 {
 210         double const ev_pos = (_orien == VERT) ? ev->y : ev->x;
 211
 212         switch (ev->button) {
 213         case 1:
 214                 if (dragging) {
 215                         remove_modal_grab();
 216                         dragging = false;
 217
 218                         if (ev_pos == grab_start) {
 219
 220                                 /* no motion - just a click */
 221
 222                                 if (ev->state & Keyboard::TertiaryModifier) {
 223                                         adjustment.set_value (default_value);
 224                                 } else if (ev->state & fine_scale_modifier) {
 225                                         adjustment.set_value (adjustment.get_lower());
 226                                 } else if ((_orien == VERT && ev_pos < span - display_span()) || (_orien == HORIZ && ev_pos > span - display_span())) {
 227                                         /* above the current display height, remember X Window coords */
 228                                         adjustment.set_value (adjustment.get_value() + adjustment.get_step_increment());
 229                                 } else {
 230                                         adjustment.set_value (adjustment.get_value() - adjustment.get_step_increment());
 231                                 }
 232                         }
 233
 234                 }
 235                 break;
 236
 237         case 2:
 238                 if (dragging) {
 239                         remove_modal_grab();
 240                         dragging = false;
 241                         set_adjustment_from_event (ev);
 242                 }
 243                 break;
 244
 245         default:
 246                 break;
 247         }
 248
 249         return false;
 250 }
 251
 252 bool
 253 PixFader::on_scroll_event (GdkEventScroll* ev)
 254 {
 255         double scale;
 256         bool ret = false;
 257
 258         if (ev->state & fine_scale_modifier) {
 259                 if (ev->state & extra_fine_scale_modifier) {
 260                         scale = 0.01;
 261                 } else {
 262                         scale = 0.05;
 263                 }
 264         } else {
 265                 scale = 0.25;
 266         }
 267
 268         if (_orien == VERT) {
 269
 270                 /* should left/right scroll affect vertical faders ? */
 271
 272                 switch (ev->direction) {
 273
 274                 case GDK_SCROLL_UP:
 275                         adjustment.set_value (adjustment.get_value() + (adjustment.get_page_increment() * scale));
 276                         ret = true;
 277                         break;
 278                 case GDK_SCROLL_DOWN:
 279                         adjustment.set_value (adjustment.get_value() - (adjustment.get_page_increment() * scale));
 280                         ret = true;
 281                         break;
 282                 default:
 283                         break;
 284                 }
 285         } else {
 286
 287                 /* up/down scrolls should definitely affect horizontal faders
 288                    because they are so much easier to use
 289                 */
 290
 291                 switch (ev->direction) {
 292
 293                 case GDK_SCROLL_RIGHT:
 294                 case GDK_SCROLL_UP:
 295                         adjustment.set_value (adjustment.get_value() + (adjustment.get_page_increment() * scale));
 296                         ret = true;
 297                         break;
 298                 case GDK_SCROLL_LEFT:
 299                 case GDK_SCROLL_DOWN:
 300                         adjustment.set_value (adjustment.get_value() - (adjustment.get_page_increment() * scale));
 301                         ret = true;
 302                         break;
 303                 default:
 304                         break;
 305                 }
 306         }
 307         return ret;
 308 }
 309
 310 bool
 311 PixFader::on_motion_notify_event (GdkEventMotion* ev)
 312 {
 313         if (dragging) {
 314                 double scale = 1.0;
 315                 double const ev_pos = (_orien == VERT) ? ev->y : ev->x;
 316
 317                 if (ev->window != grab_window) {
 318                         grab_loc = ev_pos;
 319                         grab_window = ev->window;
 320                         return true;
 321                 }
 322
 323                 if (ev->state & fine_scale_modifier) {
 324                         if (ev->state & extra_fine_scale_modifier) {
 325                                 scale = 0.05;
 326                         } else {
 327                                 scale = 0.1;
 328                         }
 329                 }
 330
 331                 double const delta = ev_pos - grab_loc;
 332                 grab_loc = ev_pos;
 333
 334                 double fract = (delta / span);
 335
 336                 fract = min (1.0, fract);
 337                 fract = max (-1.0, fract);
 338
 339                 // X Window is top->bottom for 0..Y
 340
 341                 if (_orien == VERT) {
 342                         fract = -fract;
 343                 }
 344
 345                 std::cerr << "Motion tries to set adjustment to "
 346                           << adjustment.get_value() + scale * fract * (adjustment.get_upper() - adjustment.get_lower())
 347                           << " val = " << adjustment.get_value() << " upper = " << adjustment.get_upper() << " lower = " << adjustment.get_lower()
 348                           << " fract = " << fract
 349                           << std::endl;
 350
 351                 adjustment.set_value (adjustment.get_value() + scale * fract * (adjustment.get_upper() - adjustment.get_lower()));
 352         }
 353
 354         return true;
 355 }
 356
 357 void
 358 PixFader::adjustment_changed ()
 359 {
 360         if (display_span() != last_drawn) {
 361                 queue_draw ();
 362         }
 363 }
 364
 365 /** @return pixel offset of the current value from the right or bottom of the fader */
 366 int
 367 PixFader::display_span ()
 368 {
 369         float fract = (adjustment.get_value () - adjustment.get_lower()) / ((adjustment.get_upper() - adjustment.get_lower()));
 370         return (_orien != VERT) ? (int)floor (span * (1.0 - fract)) : (int)floor (span * fract);
 371 }
 372
 373 void
 374 PixFader::set_fader_length (int l)
 375 {
 376         if (_orien == VERT) {
 377                 view.height = span = l;
 378                 unity_loc = (int) rint (view.height - (default_value * view.height)) - 1;
 379         } else {
 380                 view.width = span = l;
 381                 unity_loc = (int) rint (default_value * view.width);
 382         }
 383
 384         queue_draw ();
 385 }
 386
 387 bool
 388 PixFader::on_enter_notify_event (GdkEventCrossing*)
 389 {
 390         Keyboard::magic_widget_grab_focus ();
 391         return false;
 392 }
 393
 394 bool
 395 PixFader::on_leave_notify_event (GdkEventCrossing*)
 396 {
 397         Keyboard::magic_widget_drop_focus();
 398         return false;
 399 }
 400
 401 void
 402 PixFader::set_adjustment_from_event (GdkEventButton* ev)
 403 {
 404         double fract = (_orien == VERT) ? (1.0 - (ev->y / span)) : (ev->x / span);
 405
 406         fract = min (1.0, fract);
 407         fract = max (0.0, fract);
 408
 409         adjustment.set_value (fract * (adjustment.get_upper () - adjustment.get_lower ()));
 410 }