Intel's Mesa Driver Gets Patches For New EXT_shader_framebuffer_fetch

Open-source Intel driver developer Francisco Jerez has sent out a set of 15 patches implementing a new version of the EXT_shader_framebuffer_fetch OpenGL extension.

EXT_shader_framebuffer_fetch in its current form on the OpenGL registry is for OpenGL ES 2.0+ and allows a fragment shader to read existing frame-buffer data as input. This is intended to allow for more advanced compositing operations.

But that public version is revision six of the extension while Khronos members internally have been working on a seventh revision. It's the seventh revision that these patches implement. That new version of the specification isn't yet publicly available but the patch message makes it known that EXT_shader_framebuffer_fetch will now work with conventional desktop OpenGL rather than just OpenGL ES. There are also some improvements worked in to benefit Mesa.

These patches also implement EXT_shader_framebuffer_fetch_non_coherent as an OpenGL extension that isn't published yet but presumably just for allowing shader frame-buffer fetches on non-coherent / relaxed coherency frame-buffer memory, similar to Qualcomm's existing QCOM_shader_framebuffer_fetch_noncoherent extension.

These 15 latest Intel i965 OpenGL driver patches can be found on Mesa-dev.