Make drawing even faster (in most cases)

1 files changed, 29 insertions, 8 deletions

diff --git a/window.c b/window.c
index 03de0dc..36d4e78 100644
--- a/window.c
+++ b/window.c
@@ -62,6 +62,20 @@ compute_size (Window *window, int *w, int *h)
 }
 
 static void
+initialize_bg (GtkWidget *drawing_area, GdkRegion *region)
+{
+    GdkWindowObject *private = (GdkWindowObject *)drawing_area->window;
+    GdkGC *gc = gdk_gc_new (drawing_area->window);
+
+    gdk_gc_set_rgb_fg_color (gc, &(private->bg_color));
+    gdk_gc_set_clip_region (gc, region);
+
+    gdk_draw_rectangle (drawing_area->window, gc, TRUE, 0, 0, -1, -1);
+
+    g_object_unref (gc);
+}
+
+static void
 paint_rect (GtkWidget *drawing_area, GdkRectangle *area, Window *window)
 {
     GdkPixbuf *tmp;
@@ -70,6 +84,7 @@ paint_rect (GtkWidget *drawing_area, GdkRectangle *area, Window *window)
     int window_width, window_height;
     GdkRectangle image;
     guint32 color1, color2;
+    GdkRegion *bg_reg, *image_reg;
 
     gdk_window_get_size (drawing_area->window, &window_width, &window_height);
 
@@ -81,6 +96,16 @@ paint_rect (GtkWidget *drawing_area, GdkRectangle *area, Window *window)
 
     if (image.height < window_height)
 	image.y = (window_height - image.height) / 2;
+
+    bg_reg = gdk_region_rectangle (area);
+    image_reg = gdk_region_rectangle (&image);
+
+    gdk_region_subtract (bg_reg, image_reg);
+
+    initialize_bg (drawing_area, bg_reg);
+
+    gdk_region_destroy (bg_reg);
+    gdk_region_destroy (image_reg);
     
     if (!gdk_rectangle_intersect (area, &image, &dest))
 	return;
@@ -131,6 +156,7 @@ static gboolean
 on_expose (GtkWidget *drawing_area, GdkEventExpose *expose, Window *window)
 {
     GdkRectangle *rects;
+    GdkGC *gc;
     int n_rects;
     int i;
     
@@ -141,19 +167,11 @@ on_expose (GtkWidget *drawing_area, GdkEventExpose *expose, Window *window)
 	return;
 
     gdk_region_get_rectangles (expose->region, &rects, &n_rects);
-
-#if 0
-    g_print ("painting %d rectangles\n", n_rects);
-#endif
     
     for (i = 0; i < n_rects; ++i)
 	paint_rect (drawing_area, &(rects[i]), window);
 
     g_free (rects);
-#if 0
-
-    g_print ("done painting\n");
-#endif
     
     return TRUE;
 }
@@ -908,6 +926,9 @@ window_new (App *app)
     gtk_widget_add_events (get_widget (window, "drawing_area"),
 			   GDK_SCROLL_MASK |
 			   GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK);
+
+    gtk_widget_set_double_buffered (get_widget (window, "drawing_area"), FALSE);
+    
     gtk_widget_set_redraw_on_allocate (get_widget (window, "drawing_area"), FALSE);
 
     gtk_widget_realize (get_widget (window, "main_window"));