Mesa Gets Plumbed For Conservative Rasterization Support

An independent contributor to Mesa has posted a set of patches for implementing NVIDIA's OpenGL conservative rasterization extensions.

Nearly one thousand lines of code is now available for getting GL_NV_conservative_raster and friends wired into core Mesa and Gallium3D while getting it working for the Nouveau NVC0 driver on Maxwell GPUs and newer. Besides GL_NV_conservative_raster is the NV_conservative_raster_dilate and NV_conservative_raster_pre_snap_triangles extensions too.

The conservative rasterization mode can be used for binning to a low-resolution render target. NVIDIA has supported conservative rasterization since Maxwell GPUs and with their drivers supports it both for OpenGL and Vulkan. NVIDIA has a great and thorough guide on their conservative rasterization work via this developer blog post.

The four current Mesa patches working on this rasterization mode can be found via the Mesa-dev list.