On Mon, 2019-04-29 at 20:35 -0400, Marek Olšák wrote: > Yeah that's possible. The thing is that a GL context can have a > doublebuffered config and begin with GL_BACK as the draw buffer, but > MakeCurrent can set a pbuffer with a singlebuffered config and then > nothing is rendered with Mesa because there is no back buffer. This > case appears to work on NVIDIA.
Okay, that makes sense. Thanks for the explanation. I think this is only true because of EGL_KHR_no_config_context? If the context has a config, then you shouldn't be able to make a single- buffered pbuffer current to a double-buffered context. EGL section 2.2's definition of compatibility includes having "color and ancillary buffers of the same depth"; if you don't have a back buffer, then you have zero bits of back buffer, and you would not be compatible with non-zero bits of back buffer. I would think, anyway. Now if you bind a single-buffered pbuffer to a no-config context, obviously rendering should go to GL_FRONT. - ajax _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
