app: add simple macros GIMP_TIMER_START() and GIMP_TIMER_END()

which measure the time taken between them and print out a message.
Use it for projection benchmarking and add timing to scaling.

app/actions/debug-commands.c

@@ -31,6 +31,7 @@
 #include "base/tile.h"
 
 #include "core/gimp.h"
+#include "core/gimp-utils.h"
 #include "core/gimpcontext.h"
 #include "core/gimpimage.h"
 #include "core/gimplayer.h"
@@ -291,7 +292,6 @@ debug_benchmark_projection (GimpImage *image)
 {
   GimpProjection *projection = gimp_image_get_projection (image);
   TileManager    *tiles;
-  GTimer         *timer;
   gint            x, y;
 
   gimp_image_invalidate (image,
@@ -302,7 +302,7 @@ debug_benchmark_projection (GimpImage *image)
 
   tiles = gimp_pickable_get_tiles (GIMP_PICKABLE (projection));
 
-  timer = g_timer_new ();
+  GIMP_TIMER_START ();
 
   for (x = 0; x < tile_manager_width (tiles); x += TILE_WIDTH)
     {
@@ -314,10 +314,7 @@ debug_benchmark_projection (GimpImage *image)
         }
     }
 
-  g_print ("Validation of the entire projection took %.0f ms\n",
-           1000 * g_timer_elapsed (timer, NULL));
-
-  g_timer_destroy (timer);
+  GIMP_TIMER_END ("Validation of the entire projection");
 
   g_object_unref (image);
 

app/core/gimp-utils.h

@@ -19,6 +19,15 @@
 #define __APP_GIMP_UTILS_H__
 
 
+#define GIMP_TIMER_START() \
+  { GTimer *_timer = g_timer_new ();
+
+#define GIMP_TIMER_END(message) \
+  g_printerr ("%s: " message " took %0.2f seconds\n", \
+              G_STRFUNC, g_timer_elapsed (_timer, NULL)); \
+  g_timer_destroy (_timer); }
+
+
 gint64       gimp_g_type_instance_get_memsize      (GTypeInstance   *instance);
 gint64       gimp_g_object_get_memsize             (GObject         *object);
 gint64       gimp_g_hash_table_get_memsize         (GHashTable      *hash,

app/core/gimpdrawable.c

@@ -36,6 +36,7 @@
 #include "gegl/gimp-gegl-utils.h"
 
 #include "gimp.h" /* temp for gimp_use_gegl() */
+#include "gimp-utils.h" /* temp for GIMP_TIMER */
 #include "gimpchannel.h"
 #include "gimpcontext.h"
 #include "gimpdrawable-combine.h"
@@ -460,6 +461,8 @@ gimp_drawable_scale (GimpItem              *item,
 
   new_tiles = tile_manager_new (new_width, new_height, drawable->bytes);
 
+  GIMP_TIMER_START ();
+
   if (gimp_use_gegl (gimp_item_get_image (item)->gimp) &&
       ! gimp_drawable_is_indexed (drawable)            &&
       interpolation_type != GIMP_INTERPOLATION_LANCZOS)
@@ -511,6 +514,8 @@ gimp_drawable_scale (GimpItem              *item,
                     progress);
     }
 
+  GIMP_TIMER_END ("scaling");
+
   gimp_drawable_set_tiles_full (drawable, gimp_item_is_attached (item), NULL,
                                 new_tiles, gimp_drawable_type (drawable),
                                 new_offset_x, new_offset_y);