[gimp] app: Make drawable updates happen at fixed framerate

[Alexia Death <alexiade src gnome org>]

commit 32aca3c8b68c77d69ef3b8f5facb42d235491638
Author: Alexia Death <alexiadeath gmail com>
Date:   Sun Apr 18 15:52:17 2010 +0300

    app: Make drawable updates happen at fixed framerate

 app/core/gimpdrawable.c |   55 +++++++++++++++++++++++++++++++++++++++++++++-
 app/core/gimpdrawable.h |    9 +++++++
 2 files changed, 62 insertions(+), 2 deletions(-)
---
diff --git a/app/core/gimpdrawable.c b/app/core/gimpdrawable.c
index 887769c..9222036 100644
--- a/app/core/gimpdrawable.c
+++ b/app/core/gimpdrawable.c
@@ -18,6 +18,7 @@
 #include "config.h"
 
 #include <gegl.h>
+
 #include <gegl-plugin.h>
 
 #include "libgimpbase/gimpbase.h"
@@ -125,6 +126,8 @@ static void       gimp_drawable_real_update        (GimpDrawable      *drawable,
                                                     gint               width,
                                                     gint               height);
 
+static gboolean   gimp_drawable_update_timeout     (GimpDrawable *drawable);
+
 static gint64  gimp_drawable_real_estimate_memsize (const GimpDrawable *drawable,
                                                     gint               width,
                                                     gint               height);
@@ -256,6 +259,14 @@ gimp_drawable_init (GimpDrawable *drawable)
   drawable->bytes     = 0;
   drawable->type      = -1;
   drawable->has_alpha = FALSE;
+
+  drawable->dirty_x1 = 0;
+  drawable->dirty_y1 = 0;
+  drawable->dirty_x2 = 0;
+  drawable->dirty_y2 = 0;
+
+  drawable->update_count = 0;
+  drawable->update_timeout = 0;
 }
 
 /* sorry for the evil casts */
@@ -1197,8 +1208,36 @@ gimp_drawable_update (GimpDrawable *drawable,
 {
   g_return_if_fail (GIMP_IS_DRAWABLE (drawable));
 
-  g_signal_emit (drawable, gimp_drawable_signals[UPDATE], 0,
-                 x, y, width, height);
+  if (drawable->update_timeout > 0)
+    {
+
+      drawable->dirty_x1 = MIN (x, drawable->dirty_x1);
+      drawable->dirty_y1 = MIN (y, drawable->dirty_y1);
+
+      drawable->dirty_x2 = MAX (x + width, drawable->dirty_x2);
+
+      drawable->dirty_y2 = MAX (y + height, drawable->dirty_y2);
+
+      drawable->update_count = drawable->update_count + 1;
+    }
+  else
+    {
+      g_signal_emit (drawable, gimp_drawable_signals[UPDATE], 0,
+                     x, y, width, height);
+
+      drawable->dirty_x1 = drawable->dirty_x2;
+      drawable->dirty_y1 = drawable->dirty_y2;
+      drawable->dirty_x2 = 0;
+      drawable->dirty_y2 = 0;
+
+      drawable->update_count = 0;
+
+      drawable->update_timeout =
+          g_timeout_add_full (G_PRIORITY_HIGH,
+                              40,
+                              (GSourceFunc) gimp_drawable_update_timeout,
+                              drawable, NULL);
+    }
 }
 
 void
@@ -1996,3 +2035,15 @@ gimp_drawable_detach_floating_sel (GimpDrawable *drawable,
 
   gimp_image_set_floating_selection (image, NULL);
 }
+
+static gboolean
+gimp_drawable_update_timeout (GimpDrawable *drawable)
+{
+  drawable->update_timeout = 0;
+
+  if (drawable->update_count > 0)
+    gimp_drawable_update(drawable,
+                         drawable->dirty_x1, drawable->dirty_y1,
+                         drawable->dirty_x2 - drawable->dirty_x1, drawable->dirty_y2 - drawable->dirty_y1);
+  return FALSE;
+}
diff --git a/app/core/gimpdrawable.h b/app/core/gimpdrawable.h
index caeed82..00c6dfa 100644
--- a/app/core/gimpdrawable.h
+++ b/app/core/gimpdrawable.h
@@ -41,6 +41,15 @@ struct _GimpDrawable
   GimpImageType  type;               /* type of drawable               */
   gboolean       has_alpha;          /* drawable has alpha             */
 
+  gint           dirty_x1;
+  gint           dirty_y1;
+  gint           dirty_x2;
+  gint           dirty_y2;
+
+  guint          update_timeout;     /* update delay timeout ID         */
+
+  guint          update_count;
+
   GimpDrawablePrivate *private;
 };