Pileus Git - ~andy/gtk/blob - gtk/gtktimeline.c

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 2007 Carlos Garnacho <carlos@imendio.com>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Library General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library 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 GNU
  12  * Library General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Library General Public
  15  * License along with this library. If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <gtk/gtktimeline.h>
  19 #include <gtk/gtktypebuiltins.h>
  20 #include <gtk/gtksettings.h>
  21 #include <math.h>
  22
  23 #define MSECS_PER_SEC 1000
  24 #define FRAME_INTERVAL(nframes) (MSECS_PER_SEC / nframes)
  25 #define DEFAULT_FPS 30
  26
  27 typedef struct GtkTimelinePriv GtkTimelinePriv;
  28
  29 struct GtkTimelinePriv
  30 {
  31   guint duration;
  32   guint fps;
  33   guint source_id;
  34
  35   GTimer *timer;
  36   gdouble elapsed_time;
  37
  38   gdouble progress;
  39   gdouble last_progress;
  40
  41   GdkScreen *screen;
  42
  43   GtkTimelineProgressType progress_type;
  44
  45   guint animations_enabled : 1;
  46   guint loop               : 1;
  47   guint direction          : 1;
  48 };
  49
  50 enum {
  51   PROP_0,
  52   PROP_FPS,
  53   PROP_DURATION,
  54   PROP_LOOP,
  55   PROP_DIRECTION,
  56   PROP_SCREEN
  57 };
  58
  59 enum {
  60   STARTED,
  61   PAUSED,
  62   FINISHED,
  63   FRAME,
  64   LAST_SIGNAL
  65 };
  66
  67 static guint signals [LAST_SIGNAL] = { 0, };
  68
  69
  70 static void  gtk_timeline_set_property  (GObject         *object,
  71                                          guint            prop_id,
  72                                          const GValue    *value,
  73                                          GParamSpec      *pspec);
  74 static void  gtk_timeline_get_property  (GObject         *object,
  75                                          guint            prop_id,
  76                                          GValue          *value,
  77                                          GParamSpec      *pspec);
  78 static void  _gtk_timeline_finalize     (GObject *object);
  79
  80
  81 G_DEFINE_TYPE (GtkTimeline, _gtk_timeline, G_TYPE_OBJECT)
  82
  83
  84 static void
  85 _gtk_timeline_class_init (GtkTimelineClass *klass)
  86 {
  87   GObjectClass *object_class = G_OBJECT_CLASS (klass);
  88
  89   object_class->set_property = gtk_timeline_set_property;
  90   object_class->get_property = gtk_timeline_get_property;
  91   object_class->finalize = _gtk_timeline_finalize;
  92
  93   g_object_class_install_property (object_class,
  94                                    PROP_FPS,
  95                                    g_param_spec_uint ("fps",
  96                                                       "FPS",
  97                                                       "Frames per second for the timeline",
  98                                                       1, G_MAXUINT,
  99                                                       DEFAULT_FPS,
 100                                                       G_PARAM_READWRITE));
 101   g_object_class_install_property (object_class,
 102                                    PROP_DURATION,
 103                                    g_param_spec_uint ("duration",
 104                                                       "Animation Duration",
 105                                                       "Animation Duration",
 106                                                       0, G_MAXUINT,
 107                                                       0,
 108                                                       G_PARAM_READWRITE));
 109   g_object_class_install_property (object_class,
 110                                    PROP_LOOP,
 111                                    g_param_spec_boolean ("loop",
 112                                                          "Loop",
 113                                                          "Whether the timeline loops or not",
 114                                                          FALSE,
 115                                                          G_PARAM_READWRITE));
 116   g_object_class_install_property (object_class,
 117                                    PROP_SCREEN,
 118                                    g_param_spec_object ("screen",
 119                                                         "Screen",
 120                                                         "Screen to get the settings from",
 121                                                         GDK_TYPE_SCREEN,
 122                                                         G_PARAM_READWRITE));
 123
 124   signals[STARTED] =
 125     g_signal_new ("started",
 126                   G_TYPE_FROM_CLASS (object_class),
 127                   G_SIGNAL_RUN_LAST,
 128                   G_STRUCT_OFFSET (GtkTimelineClass, started),
 129                   NULL, NULL,
 130                   g_cclosure_marshal_VOID__VOID,
 131                   G_TYPE_NONE, 0);
 132
 133   signals[PAUSED] =
 134     g_signal_new ("paused",
 135                   G_TYPE_FROM_CLASS (object_class),
 136                   G_SIGNAL_RUN_LAST,
 137                   G_STRUCT_OFFSET (GtkTimelineClass, paused),
 138                   NULL, NULL,
 139                   g_cclosure_marshal_VOID__VOID,
 140                   G_TYPE_NONE, 0);
 141
 142   signals[FINISHED] =
 143     g_signal_new ("finished",
 144                   G_TYPE_FROM_CLASS (object_class),
 145                   G_SIGNAL_RUN_LAST,
 146                   G_STRUCT_OFFSET (GtkTimelineClass, finished),
 147                   NULL, NULL,
 148                   g_cclosure_marshal_VOID__VOID,
 149                   G_TYPE_NONE, 0);
 150
 151   signals[FRAME] =
 152     g_signal_new ("frame",
 153                   G_TYPE_FROM_CLASS (object_class),
 154                   G_SIGNAL_RUN_LAST,
 155                   G_STRUCT_OFFSET (GtkTimelineClass, frame),
 156                   NULL, NULL,
 157                   g_cclosure_marshal_VOID__DOUBLE,
 158                   G_TYPE_NONE, 1,
 159                   G_TYPE_DOUBLE);
 160
 161   g_type_class_add_private (klass, sizeof (GtkTimelinePriv));
 162 }
 163
 164 static void
 165 _gtk_timeline_init (GtkTimeline *timeline)
 166 {
 167   GtkTimelinePriv *priv;
 168
 169   priv = timeline->priv = G_TYPE_INSTANCE_GET_PRIVATE (timeline,
 170                                                        GTK_TYPE_TIMELINE,
 171                                                        GtkTimelinePriv);
 172
 173   priv->fps = DEFAULT_FPS;
 174   priv->duration = 0.0;
 175   priv->direction = GTK_TIMELINE_DIRECTION_FORWARD;
 176   priv->screen = gdk_screen_get_default ();
 177
 178   priv->last_progress = 0;
 179 }
 180
 181 static void
 182 gtk_timeline_set_property (GObject      *object,
 183                            guint         prop_id,
 184                            const GValue *value,
 185                            GParamSpec   *pspec)
 186 {
 187   GtkTimeline *timeline;
 188
 189   timeline = GTK_TIMELINE (object);
 190
 191   switch (prop_id)
 192     {
 193     case PROP_FPS:
 194       _gtk_timeline_set_fps (timeline, g_value_get_uint (value));
 195       break;
 196     case PROP_DURATION:
 197       _gtk_timeline_set_duration (timeline, g_value_get_uint (value));
 198       break;
 199     case PROP_LOOP:
 200       _gtk_timeline_set_loop (timeline, g_value_get_boolean (value));
 201       break;
 202     case PROP_DIRECTION:
 203       _gtk_timeline_set_direction (timeline, g_value_get_enum (value));
 204       break;
 205     case PROP_SCREEN:
 206       _gtk_timeline_set_screen (timeline,
 207                                 GDK_SCREEN (g_value_get_object (value)));
 208       break;
 209     default:
 210       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 211     }
 212 }
 213
 214 static void
 215 gtk_timeline_get_property (GObject    *object,
 216                            guint       prop_id,
 217                            GValue     *value,
 218                            GParamSpec *pspec)
 219 {
 220   GtkTimeline *timeline;
 221   GtkTimelinePriv *priv;
 222
 223   timeline = GTK_TIMELINE (object);
 224   priv = timeline->priv;
 225
 226   switch (prop_id)
 227     {
 228     case PROP_FPS:
 229       g_value_set_uint (value, priv->fps);
 230       break;
 231     case PROP_DURATION:
 232       g_value_set_uint (value, priv->duration);
 233       break;
 234     case PROP_LOOP:
 235       g_value_set_boolean (value, priv->loop);
 236       break;
 237     case PROP_DIRECTION:
 238       g_value_set_enum (value, priv->direction);
 239       break;
 240     case PROP_SCREEN:
 241       g_value_set_object (value, priv->screen);
 242       break;
 243     default:
 244       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 245     }
 246 }
 247
 248 static void
 249 _gtk_timeline_finalize (GObject *object)
 250 {
 251   GtkTimelinePriv *priv;
 252   GtkTimeline *timeline;
 253
 254   timeline = (GtkTimeline *) object;
 255   priv = timeline->priv;
 256
 257   if (priv->source_id)
 258     {
 259       g_source_remove (priv->source_id);
 260       priv->source_id = 0;
 261     }
 262
 263   if (priv->timer)
 264     g_timer_destroy (priv->timer);
 265
 266   G_OBJECT_CLASS (_gtk_timeline_parent_class)->finalize (object);
 267 }
 268
 269 static gdouble
 270 calculate_progress (gdouble                 linear_progress,
 271                     GtkTimelineProgressType progress_type)
 272 {
 273   gdouble progress;
 274
 275   progress = linear_progress;
 276
 277   switch (progress_type)
 278     {
 279     case GTK_TIMELINE_PROGRESS_LINEAR:
 280       break;
 281     case GTK_TIMELINE_PROGRESS_EASE_IN_OUT:
 282       progress *= 2;
 283
 284       if (progress < 1)
 285         progress = pow (progress, 3) / 2;
 286       else
 287         progress = (pow (progress - 2, 3) + 2) / 2;
 288
 289       break;
 290     case GTK_TIMELINE_PROGRESS_EASE:
 291       progress = (sin ((progress - 0.5) * G_PI) + 1) / 2;
 292       break;
 293     case GTK_TIMELINE_PROGRESS_EASE_IN:
 294       progress = pow (progress, 3);
 295       break;
 296     case GTK_TIMELINE_PROGRESS_EASE_OUT:
 297       progress = pow (progress - 1, 3) + 1;
 298       break;
 299     default:
 300       g_warning ("Timeline progress type not implemented");
 301     }
 302
 303   return progress;
 304 }
 305
 306 static gboolean
 307 gtk_timeline_run_frame (GtkTimeline *timeline)
 308 {
 309   GtkTimelinePriv *priv;
 310   gdouble delta_progress, progress;
 311
 312   /* the user may unref us during the signals, so save ourselves */
 313   g_object_ref (timeline);
 314
 315   priv = timeline->priv;
 316
 317   priv->elapsed_time = (guint) (g_timer_elapsed (priv->timer, NULL) * 1000);
 318   g_timer_start (priv->timer);
 319
 320   if (priv->animations_enabled)
 321     {
 322       delta_progress = (gdouble) priv->elapsed_time / priv->duration;
 323       progress = priv->last_progress;
 324
 325       if (priv->direction == GTK_TIMELINE_DIRECTION_BACKWARD)
 326         progress -= delta_progress;
 327       else
 328         progress += delta_progress;
 329
 330       priv->last_progress = progress;
 331
 332       progress = CLAMP (progress, 0., 1.);
 333     }
 334   else
 335     progress = (priv->direction == GTK_TIMELINE_DIRECTION_FORWARD) ? 1.0 : 0.0;
 336
 337   priv->progress = progress;
 338   g_signal_emit (timeline, signals [FRAME], 0,
 339                  calculate_progress (progress, priv->progress_type));
 340
 341   if ((priv->direction == GTK_TIMELINE_DIRECTION_FORWARD && progress == 1.0) ||
 342       (priv->direction == GTK_TIMELINE_DIRECTION_BACKWARD && progress == 0.0))
 343     {
 344       gboolean loop;
 345
 346       loop = priv->loop && priv->animations_enabled;
 347
 348       if (loop)
 349         _gtk_timeline_rewind (timeline);
 350       else
 351         {
 352           if (priv->source_id)
 353             {
 354               g_source_remove (priv->source_id);
 355               priv->source_id = 0;
 356             }
 357           g_timer_stop (priv->timer);
 358           g_signal_emit (timeline, signals [FINISHED], 0);
 359           g_object_unref (timeline);
 360           return FALSE;
 361         }
 362     }
 363
 364   g_object_unref (timeline);
 365
 366   return TRUE;
 367 }
 368
 369 /*
 370  * _gtk_timeline_new:
 371  * @duration: duration in milliseconds for the timeline
 372  *
 373  * Creates a new #GtkTimeline with the specified number of frames.
 374  *
 375  * Return Value: the newly created #GtkTimeline
 376  */
 377 GtkTimeline *
 378 _gtk_timeline_new (guint duration)
 379 {
 380   return g_object_new (GTK_TYPE_TIMELINE,
 381                        "duration", duration,
 382                        NULL);
 383 }
 384
 385 GtkTimeline *
 386 _gtk_timeline_new_for_screen (guint      duration,
 387                               GdkScreen *screen)
 388 {
 389   return g_object_new (GTK_TYPE_TIMELINE,
 390                        "duration", duration,
 391                        "screen", screen,
 392                        NULL);
 393 }
 394
 395 /*
 396  * _gtk_timeline_start:
 397  * @timeline: A #GtkTimeline
 398  *
 399  * Runs the timeline from the current frame.
 400  */
 401 void
 402 _gtk_timeline_start (GtkTimeline *timeline)
 403 {
 404   GtkTimelinePriv *priv;
 405   GtkSettings *settings;
 406   gboolean enable_animations = FALSE;
 407
 408   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 409
 410   priv = timeline->priv;
 411
 412   if (!priv->source_id)
 413     {
 414       if (priv->timer)
 415         g_timer_continue (priv->timer);
 416       else
 417         priv->timer = g_timer_new ();
 418
 419       /* sanity check */
 420       g_assert (priv->fps > 0);
 421
 422       if (priv->screen)
 423         {
 424           settings = gtk_settings_get_for_screen (priv->screen);
 425           g_object_get (settings, "gtk-enable-animations", &enable_animations, NULL);
 426         }
 427
 428       priv->animations_enabled = enable_animations;
 429
 430       g_signal_emit (timeline, signals [STARTED], 0);
 431
 432       if (enable_animations)
 433         priv->source_id = gdk_threads_add_timeout (FRAME_INTERVAL (priv->fps),
 434                                                    (GSourceFunc) gtk_timeline_run_frame,
 435                                                    timeline);
 436       else
 437         priv->source_id = gdk_threads_add_idle ((GSourceFunc) gtk_timeline_run_frame,
 438                                                 timeline);
 439     }
 440 }
 441
 442 /*
 443  * _gtk_timeline_pause:
 444  * @timeline: A #GtkTimeline
 445  *
 446  * Pauses the timeline.
 447  */
 448 void
 449 _gtk_timeline_pause (GtkTimeline *timeline)
 450 {
 451   GtkTimelinePriv *priv;
 452
 453   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 454
 455   priv = timeline->priv;
 456
 457   if (priv->source_id)
 458     {
 459       g_timer_stop (priv->timer);
 460       g_source_remove (priv->source_id);
 461       priv->source_id = 0;
 462       g_signal_emit (timeline, signals [PAUSED], 0);
 463     }
 464 }
 465
 466 /*
 467  * _gtk_timeline_rewind:
 468  * @timeline: A #GtkTimeline
 469  *
 470  * Rewinds the timeline.
 471  */
 472 void
 473 _gtk_timeline_rewind (GtkTimeline *timeline)
 474 {
 475   GtkTimelinePriv *priv;
 476
 477   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 478
 479   priv = timeline->priv;
 480
 481   if (_gtk_timeline_get_direction (timeline) != GTK_TIMELINE_DIRECTION_FORWARD)
 482     priv->progress = priv->last_progress = 1.;
 483   else
 484     priv->progress = priv->last_progress = 0.;
 485
 486   /* reset timer */
 487   if (priv->timer)
 488     {
 489       g_timer_start (priv->timer);
 490
 491       if (!priv->source_id)
 492         g_timer_stop (priv->timer);
 493     }
 494 }
 495
 496 /*
 497  * _gtk_timeline_is_running:
 498  * @timeline: A #GtkTimeline
 499  *
 500  * Returns whether the timeline is running or not.
 501  *
 502  * Return Value: %TRUE if the timeline is running
 503  */
 504 gboolean
 505 _gtk_timeline_is_running (GtkTimeline *timeline)
 506 {
 507   GtkTimelinePriv *priv;
 508
 509   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), FALSE);
 510
 511   priv = timeline->priv;
 512
 513   return (priv->source_id != 0);
 514 }
 515
 516 /*
 517  * _gtk_timeline_get_elapsed_time:
 518  * @timeline: A #GtkTimeline
 519  *
 520  * Returns the elapsed time since the last GtkTimeline::frame signal
 521  *
 522  * Return Value: elapsed time in milliseconds since the last frame
 523  */
 524 guint
 525 _gtk_timeline_get_elapsed_time (GtkTimeline *timeline)
 526 {
 527   GtkTimelinePriv *priv;
 528
 529   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), 0);
 530
 531   priv = timeline->priv;
 532   return priv->elapsed_time;
 533 }
 534
 535 /*
 536  * _gtk_timeline_get_fps:
 537  * @timeline: A #GtkTimeline
 538  *
 539  * Returns the number of frames per second.
 540  *
 541  * Return Value: frames per second
 542  */
 543 guint
 544 _gtk_timeline_get_fps (GtkTimeline *timeline)
 545 {
 546   GtkTimelinePriv *priv;
 547
 548   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), 1);
 549
 550   priv = timeline->priv;
 551   return priv->fps;
 552 }
 553
 554 /*
 555  * _gtk_timeline_set_fps:
 556  * @timeline: A #GtkTimeline
 557  * @fps: frames per second
 558  *
 559  * Sets the number of frames per second that
 560  * the timeline will play.
 561  */
 562 void
 563 _gtk_timeline_set_fps (GtkTimeline *timeline,
 564                       guint        fps)
 565 {
 566   GtkTimelinePriv *priv;
 567
 568   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 569   g_return_if_fail (fps > 0);
 570
 571   priv = timeline->priv;
 572
 573   priv->fps = fps;
 574
 575   if (_gtk_timeline_is_running (timeline))
 576     {
 577       g_source_remove (priv->source_id);
 578       priv->source_id = gdk_threads_add_timeout (FRAME_INTERVAL (priv->fps),
 579                                                  (GSourceFunc) gtk_timeline_run_frame,
 580                                                  timeline);
 581     }
 582
 583   g_object_notify (G_OBJECT (timeline), "fps");
 584 }
 585
 586 /*
 587  * _gtk_timeline_get_loop:
 588  * @timeline: A #GtkTimeline
 589  *
 590  * Returns whether the timeline loops to the
 591  * beginning when it has reached the end.
 592  *
 593  * Return Value: %TRUE if the timeline loops
 594  */
 595 gboolean
 596 _gtk_timeline_get_loop (GtkTimeline *timeline)
 597 {
 598   GtkTimelinePriv *priv;
 599
 600   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), FALSE);
 601
 602   priv = timeline->priv;
 603   return priv->loop;
 604 }
 605
 606 /*
 607  * _gtk_timeline_set_loop:
 608  * @timeline: A #GtkTimeline
 609  * @loop: %TRUE to make the timeline loop
 610  *
 611  * Sets whether the timeline loops to the beginning
 612  * when it has reached the end.
 613  */
 614 void
 615 _gtk_timeline_set_loop (GtkTimeline *timeline,
 616                         gboolean     loop)
 617 {
 618   GtkTimelinePriv *priv;
 619
 620   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 621
 622   priv = timeline->priv;
 623
 624   if (loop != priv->loop)
 625     {
 626       priv->loop = loop;
 627       g_object_notify (G_OBJECT (timeline), "loop");
 628     }
 629 }
 630
 631 void
 632 _gtk_timeline_set_duration (GtkTimeline *timeline,
 633                             guint        duration)
 634 {
 635   GtkTimelinePriv *priv;
 636
 637   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 638
 639   priv = timeline->priv;
 640
 641   if (duration != priv->duration)
 642     {
 643       priv->duration = duration;
 644       g_object_notify (G_OBJECT (timeline), "duration");
 645     }
 646 }
 647
 648 guint
 649 _gtk_timeline_get_duration (GtkTimeline *timeline)
 650 {
 651   GtkTimelinePriv *priv;
 652
 653   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), 0);
 654
 655   priv = timeline->priv;
 656
 657   return priv->duration;
 658 }
 659
 660 /*
 661  * _gtk_timeline_set_direction:
 662  * @timeline: A #GtkTimeline
 663  * @direction: direction
 664  *
 665  * Sets the direction of the timeline.
 666  */
 667 void
 668 _gtk_timeline_set_direction (GtkTimeline          *timeline,
 669                              GtkTimelineDirection  direction)
 670 {
 671   GtkTimelinePriv *priv;
 672
 673   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 674
 675   priv = timeline->priv;
 676   priv->direction = direction;
 677 }
 678
 679 /*
 680  * _gtk_timeline_get_direction:
 681  * @timeline: A #GtkTimeline
 682  *
 683  * Returns the direction of the timeline.
 684  *
 685  * Return Value: direction
 686  */
 687 GtkTimelineDirection
 688 _gtk_timeline_get_direction (GtkTimeline *timeline)
 689 {
 690   GtkTimelinePriv *priv;
 691
 692   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), GTK_TIMELINE_DIRECTION_FORWARD);
 693
 694   priv = timeline->priv;
 695   return priv->direction;
 696 }
 697
 698 void
 699 _gtk_timeline_set_screen (GtkTimeline *timeline,
 700                           GdkScreen   *screen)
 701 {
 702   GtkTimelinePriv *priv;
 703
 704   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 705   g_return_if_fail (GDK_IS_SCREEN (screen));
 706
 707   priv = timeline->priv;
 708
 709   if (priv->screen)
 710     g_object_unref (priv->screen);
 711
 712   priv->screen = g_object_ref (screen);
 713
 714   g_object_notify (G_OBJECT (timeline), "screen");
 715 }
 716
 717 GdkScreen *
 718 _gtk_timeline_get_screen (GtkTimeline *timeline)
 719 {
 720   GtkTimelinePriv *priv;
 721
 722   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), NULL);
 723
 724   priv = timeline->priv;
 725   return priv->screen;
 726 }
 727
 728 gdouble
 729 _gtk_timeline_get_progress (GtkTimeline *timeline)
 730 {
 731   GtkTimelinePriv *priv;
 732
 733   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), 0.);
 734
 735   priv = timeline->priv;
 736   return calculate_progress (priv->progress, priv->progress_type);
 737 }
 738
 739 GtkTimelineProgressType
 740 _gtk_timeline_get_progress_type (GtkTimeline *timeline)
 741 {
 742   GtkTimelinePriv *priv;
 743
 744   g_return_val_if_fail (GTK_IS_TIMELINE (timeline), GTK_TIMELINE_PROGRESS_LINEAR);
 745
 746   priv = timeline->priv;
 747   return priv->progress_type;
 748 }
 749
 750 void
 751 _gtk_timeline_set_progress_type (GtkTimeline             *timeline,
 752                                  GtkTimelineProgressType  progress_type)
 753 {
 754   GtkTimelinePriv *priv;
 755
 756   g_return_if_fail (GTK_IS_TIMELINE (timeline));
 757
 758   priv = timeline->priv;
 759   priv->progress_type = progress_type;
 760 }