Paul Berry
b31f62c907
When rendering triangle strips, vertices come down the pipeline in the order specified, even though this causes alternate triangles to have reversed winding order. For example, if the vertices are ABCDE, then the GS is invoked on triangles ABC, BCD, and CDE, even though this means that triangle BCD is in the reverse of the normal winding order. The hardware automatically flags the triangles with reversed winding order as _3DPRIM_TRISTRIP_REVERSE, so that face culling and two-sided coloring can be adjusted to account for the reversed order. In order to ensure that winding order is correct when streaming vertices out to a transform feedback buffer, we need to alter the ordering of BCD to BDC when the first provoking vertex convention is in use, and to CBD when the last provoking vertex convention is in use. To do this, we precompute an array of indices indicating where each vertex will be placed in the transform feedback buffer; normally this is SVBI[0] + (0, 1, 2), indicating that vertex order should be preserved. When the primitive type is _3DPRIM_TRISTRIP_REVERSE, we change this order to either SVBI[0] + (0, 2, 1) or SVBI[0] + (1, 0, 2), depending on the provoking vertex convention. Fixes piglit tests "EXT_transform_feedback/tessellation triangle_strip" on Gen6. Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
File: docs/README.WIN32 Last updated: 23 April 2011 Quick Start ----- ----- Windows drivers are build with SCons. Makefiles or Visual Studio projects are no longer shipped or supported. Run scons osmesa mesagdi to build classic mesa Windows GDI drivers; or scons libgl-gdi to build gallium based GDI driver. This will work both with MSVS or Mingw. Windows Drivers ------- ------- At this time, only the gallium GDI driver is known to work. Source code also exists in the tree for other drivers in src/mesa/drivers/windows, but the status of this code is unknown. General ------- After building, you can copy the above DLL files to a place in your PATH such as $SystemRoot/SYSTEM32. If you don't like putting things in a system directory, place them in the same directory as the executable(s). Be careful about accidentially overwriting files of the same name in the SYSTEM32 directory. The DLL files are built so that the external entry points use the stdcall calling convention. Static LIB files are not built. The LIB files that are built with are the linker import files associated with the DLL files. The si-glu sources are used to build the GLU libs. This was done mainly to get the better tessellator code. If you have a Windows-related build problem or question, please post to the mesa-dev or mesa-users list.