[cairo] [patch] gl: when using a surface as source/mask in drawing operation on GL surface target, we can avoid map_to_image()

[Chris Wilson]

On Fri, 30 Mar 2012 15:16:59 +0000, "Henry (Yu) Song - SISA" <hsong at sisa.samsung.com> wrote:
> Hi, Chris
> 
> Is cairo_surface_map_to_image() calls _cairo_gl_surface_map_to_image() in which a new image surface is allocated and use glReadPixels() to read pixels from gl surface to image surface?  I could not see where PBO is allocated.

Patches welcome. :)

The reason for introducing map-to-image and create-similar-image was for
the express purpose of being able to do PBO (or SHM transport for X),
and exposing that ability to the user as well.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre