[cairo] FW: [patch] gl: disable GL_DITHER

[Henry (Yu) Song - SISA]

re-post patch
________________________________________
From: Henry (Yu) Song - SISA
Sent: Tuesday, January 29, 2013 9:30 AM
To: cairo at cairographics.org
Subject: [patch] gl: disable GL_DITHER

gl: disable GL_DITHER

Leaving GL_DITHER enabled (by default) causes color pixel mismatch on 
some drivers by comparing uploading then glReadPixels and original image



>From 08cbdc9127b8638d04f70f36545f08965fe631db Mon Sep 17 00:00:00 2001
From: Henry Song <henry.song at samsung.com>
Date: Tue, 29 Jan 2013 09:26:43 -0800
Subject: [PATCH] gl: disable GL_DITHER - GL_DITHER is enabled by default by
 spec. GL_DITHER causes color dithering before written to
 color buffer on some drivers.

---
 src/cairo-gl-device.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/cairo-gl-device.c b/src/cairo-gl-device.c
index 22297b3..b30c49c 100644
--- a/src/cairo-gl-device.c
+++ b/src/cairo-gl-device.c
@@ -725,6 +725,8 @@ _cairo_gl_context_set_destination (cairo_gl_context_t *ctx,
 #endif
     }

+    glDisable (GL_DITHER);
+
     glViewport (0, 0, surface->width, surface->height);

     if (_cairo_gl_surface_is_texture (surface))
--
1.7.9.5