Re: [patch] gl: when using a surface as source/mask in drawing operation on GL surface target, we can avoid map_to_image()
"Henry (Yu) Song - SISA" <[email protected]>
| Newsgroups | gmane.comp.lib.cairo |
|---|---|
| Message-ID | <3955FA337689574EB32F94B12A7E6E9E0B4FA48F@ex10mail> |
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. Thanks Henry -----Original Message----- From: Chris Wilson [mailto:[email protected]] Sent: Friday, March 30, 2012 8:09 AM To: Henry (Yu) Song - SISA; [email protected] Subject: RE: [cairo] [patch] gl: when using a surface as source/mask in drawing operation on GL surface target, we can avoid map_to_image() On Fri, 30 Mar 2012 15:05:44 +0000, "Henry (Yu) Song - SISA" <[email protected]> wrote: > Hi, Chris > > Do you mean the patch is OK? I don't see a need to download image from a newly created GL surface, it is just like you create a new image surface. Am I right? No, the patch forces the use of system memory when we could be allocating a PBO. Also it is performing an optimization at a higher level which I think is more suitable in map-to-image. -Chris -- Chris Wilson, Intel Open Source Technology Centre -- cairo mailing list [email protected] http://lists.cairographics.org/mailman/listinfo/cairo