From b0e1c837acea2d6a78d5e5b1a011b1d43354b3ac Mon Sep 17 00:00:00 2001
From: Andrea Canciani <ranma42@gmail.com>
Date: Fri, 7 Jan 2011 13:27:27 +0200
Subject: [PATCH] gl: Ensure that gl surface resizes are properly applied

If a gl surface is resized (with cairo_gl_surface_set_size()) while being the
current target, the resize does not take effect until the target changes to a
different surface and back to the original one. This patch allows a gl_context
to track when the current target surface has been changed and ensures that a
resize always take effect the next time a resized surface is used as the target.
---
 src/cairo-gl-device.c  | 3 ++-
 src/cairo-gl-private.h | 1 +
 src/cairo-gl-surface.c | 8 ++++++--
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/src/cairo-gl-device.c b/src/cairo-gl-device.c
index 3793f9d61..048d48b8e 100644
--- a/src/cairo-gl-device.c
+++ b/src/cairo-gl-device.c
@@ -279,12 +279,13 @@ void
 _cairo_gl_context_set_destination (cairo_gl_context_t *ctx,
                                    cairo_gl_surface_t *surface)
 {
-    if (ctx->current_target == surface)
+    if (ctx->current_target == surface && ! surface->needs_update)
         return;
 
     _cairo_gl_composite_flush (ctx);
 
     ctx->current_target = surface;
+    surface->needs_update = FALSE;
 
     if (_cairo_gl_surface_is_texture (surface)) {
         _cairo_gl_ensure_framebuffer (ctx, surface);
diff --git a/src/cairo-gl-private.h b/src/cairo-gl-private.h
index 2f47b9a4d..3eb7e0901 100644
--- a/src/cairo-gl-private.h
+++ b/src/cairo-gl-private.h
@@ -93,6 +93,7 @@ typedef struct _cairo_gl_surface {
     GLuint fb; /* GL framebuffer object wrapping our data. */
     GLuint depth; /* GL framebuffer object holding depth */
     int owns_tex;
+    cairo_bool_t needs_update;
 } cairo_gl_surface_t;
 
 typedef struct cairo_gl_glyph_cache {
diff --git a/src/cairo-gl-surface.c b/src/cairo-gl-surface.c
index 0e4d275a7..211fe0287 100644
--- a/src/cairo-gl-surface.c
+++ b/src/cairo-gl-surface.c
@@ -214,6 +214,7 @@ _cairo_gl_surface_init (cairo_device_t *device,
 
     surface->width = width;
     surface->height = height;
+    surface->needs_update = FALSE;
 }
 
 static cairo_surface_t *
@@ -465,8 +466,11 @@ cairo_gl_surface_set_size (cairo_surface_t *abstract_surface,
 	return;
     }
 
-    surface->width = width;
-    surface->height = height;
+    if (surface->width != width || surface->height != height) {
+	surface->needs_update = TRUE;
+	surface->width = width;
+	surface->height = height;
+    }
 }
 
 int