[clutter] [patch] clutter_stage_read_pixels off-by-one error

[Geoff Gustafson]

If I'm not mistaken, there's an off-by-one error in 
clutter_stage_read_pixels in this line:
y = stage_height - 1 - y - height;

It always reads an area one line lower than the user expected. Consider 
for example when the user is reading the full stage... then stage_height 
== height and y comes in as 0. This line sets the new y to -1 instead of 0.

This patch fixes the problem for me on clutter-0.8.4. It appears the 
line hasn't changed in the latest git tree.

- Geoff

diff -Naurp a/clutter/clutter-stage.c b/clutter/clutter-stage.c
--- a/clutter/clutter-stage.c   2009-01-05 15:30:02.000000000 -0800
+++ b/clutter/clutter-stage.c   2009-01-05 15:30:07.000000000 -0800
@@ -1202,7 +1202,7 @@ clutter_stage_read_pixels (ClutterStage 
 
   /* The y co-ordinate should be given in OpenGL's coordinate system
      so 0 is the bottom row */
-  y = stage_height - 1 - y - height;
+  y = stage_height - y - height;
 
   glFinish ();