On Tue, Aug 3, 2010 at 12:33 AM, Chia-I Wu <olva...@gmail.com> wrote: > While studying the draw module, I noticed that multiple primitive > decomposers exist: draw_pt_vcache_tmp.h, draw_gs_tmp.h, > draw_so_emit_tmp.h, and draw_pt_decompose.h. The differences between > them are small, yet some of them support primitive modes that others > don't. So I started the work to add a generic draw_decompose_tmp.h > that can be included by other tmp header files. You may find the > changes in the attachments, or > > http://cgit.freedesktop.org/~olv/mesa/log/?h=draw-decompose > > draw_decompose_tmp.h supports all primitive modes. While it is a > rewrite, it resembles the existing decomposers a lot. There are two > changes regarding how PIPE_PRIM_POLYGON and > PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY are decomposed. > > When flatshade_first is TRUE, the first triangle of the decomposed > polygon has edge flags 0 and 1 set; the last triangle has edge flags 1 > and 2 set; the other triangles has edge flags 1 set. This is > different from the existing decomposers, which seem to set the edge > flags wrongly(?). > > As for PIPE_PRIM_TRIANGLE_STRIP_ADJACENCY, the GS decomposer does not > seem to follow the vertex ordering of GL_TRIANGLE_STRIP_ADJACENCY. I > write that part from scratch. I am not 100% sure here as I don't have > a test case to verify. It would be great if someone can clarify. > > I haven't done a thorough (read: piglit) test yet. I would like to > get early feedback before continuing. Suggestions? I've pushed v2 of draw_decompose_tmp.h to
http://cgit.freedesktop.org/~olv/mesa/log/?h=draw-decompose-2.1 The main changes are - Fix decomposition of triangle strip with adjacency (idx[3] was updated before saved to idx[4]) - Fix several copy-and-paste errors in the comments - vcache should not decompose, for example, tri_adj to tri - Return directly for impossible primitive types to help the compiler generate better code - Rename the local variable flatfirst to last_vertex_last and invert its meaning, as the variable is used to control how a bigger primitive is decomposed. For example, a triangle strip with vertices [0, 1, 2, 3] will be decomposed to two triangles with vertices [0, 1, 2] and [2, 1, 3] respectively when last_vertex_last is TRUE (note that the last vertex of each triangle is emitted last); it will be decomposed to [0, 1, 2] and [0, 2, 1] when last_vertex_last is FALSE (note that the first vertex of each triangle is emitted first). Zack has helped a lot while I am updating the patches (big thanks!). The patches have been verified with piglit (only those in glean) and manually verified with a dozen of demos (in demos/src/trivial). If there is no objection, I'd like to commit the patches tomorrow. -- o...@lunarg.com _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
