some background: so on r600g, the only way to directly write to the stencil is via the shader, using a transfer would require an extra step to flush the DS buffer out via the pipe again to make it useable by the hw as a DS buffer. So using the current gallium stencil draw would be a major overhead, compared to just doing it properly.
So to do it properly I decided to expose the GL_ARB_shader_stencil_export type functionality. http://cgit.freedesktop.org/~airlied/mesa/log/?h=gallium-stencil-export 7 commits in here: two simple one liners, add the cap to gallium headers, and add FRAG_RESULT_STENCIL to mesa. then a "fix" to the mesa texstore so it will store S8 in an 8/24 so we can put the stencil values in a texture. mesa state tracker support to use the new capability to hw accel drawpixels on the stencil (outputs to Y of FRAG_RESULT_STENCIL). r600g support for the capability take the second TGSI_SEMANTIC_POSITION output and use its Y value as stencil (looking at this now, I should probably be taking the X value really). very initial mesa/GLSL support for the extension (completely untested). initial softpipe support for the capability a demonstration. TODO: probably stop using Y (this was just because the hw uses Y), the GLSL extension just defines an integer output for the fragprog. fix the 24/8 texstore variant. write some test code for piglit and test the GL extension/GLSL bits. I'm a lot more interested in the non-GL extension bits as it allows stencil writes to work properly on r600g. Dave. _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
