Eric Anholt wrote: > Module: Mesa > Branch: master > Commit: 2792baec343e5773ff51e93c1b6df8b63d3af4af > URL: > http://cgit.freedesktop.org/mesa/mesa/commit/?id=2792baec343e5773ff51e93c1b6df8b63d3af4af > > Author: Eric Anholt <e...@anholt.net> > Date: Tue Jan 26 18:04:03 2010 -0800 > > intel: Remove dead code from having to clip copyteximage source rect. > > mesa core does it now. If only it did so for other entrypoints.
There's actually a subtle reason why core Mesa doesn't do clipping for all the glDrawPixels/CopyPixels/etc functions. The GL spec says that pixel-transfer ops such as histograms and minmax are applied before fragments are clipped/culled. Mesa allows the driver functions to take a crack at applying any/all pixel transfer operations (scale/bias, LUT, histogram, etc). If the driver can do those things, great. Otherwise a sw fallback is used. If we clipped glDrawPixels (for example) in core Mesa before doing pixel transfer ops and before calling the driver function that would upset the histogram/minmax outcome. That said, this is a pretty obscure case and we've never had a driver implement histograms. But that's why. There are utility functions such as _mesa_clip_pixels() that drivers can use to do clipping. -Brian ------------------------------------------------------------------------------ The Planet: dedicated and managed hosting, cloud storage, colocation Stay online with enterprise data centers and the best network in the business Choose flexible plans and management services without long-term contracts Personal 24x7 support from experience hosting pros just a phone call away. http://p.sf.net/sfu/theplanet-com _______________________________________________ Mesa3d-dev mailing list Mesa3d-dev@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mesa3d-dev
