On Fri, May 11, 2012 at 10:49 AM, Ian Romanick <i...@freedesktop.org> wrote: > On 05/11/2012 10:35 AM, Marek Olšák wrote: >> On Fri, May 11, 2012 at 7:17 PM, Brian Paul<bri...@vmware.com> wrote: >>> So setting MESA_EXTENSION_OVERRIDE=-GL_NV_primitive_restart should be an >>> option. The o(dummy_true) convention might prevent that, but I haven't >>> tested that... >> >> In that case, I think we should disable it in the state tracker if >> there's no driver support. If it's faster for svga, it's very likely >> faster for the other DX9-level drivers too. > > I can imagine that it's certainly faster for hardware TNL cards. Mapping an > index buffer that's probably in VRAM, scanning it on the CPU, then > submitting multiple draw calls doesn't even sound like it would be fast.
Drivers can disable software support in one of two ways: 1. gallium: enable PIPE_CAP_PRIMITIVE_RESTART 2. set ctx->Const.PrimitiveRestartInSoftware = GL_FALSE, (similar to patch 3/8 which implements #1 for gallium) The driver can still call vbo_sw_primitive_restart if they want to take the software path. > It also seems like the pure software paths might want to handle it directly > in their index processing loop rather than chopping up the draw call before > hand. Do you mean it is better to not advertise the extension and let GL API users handle this? > The real value of these software paths is handling cases that the hardware > can't do. The GL spec allows any value to be specified for the restart > index, but some hardware (*cough*) only supports ~0. So, what is the consensus here? I believe that state_tracker enables the NV_primitive_restart extension for all gallium drivers currently, and enables software support for drivers that don't advertise the support. So, this changeset essentially mirrors that behaviour, but under vbo. -Jordan _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
