WIP: egl: add EGL_HOST_POINTER_MESA
This is an attempt to add a way for EGL clients to tell software renderers like llvmpipe to render to an existing chunk of memory. The end goal is to allow llvmpipe to work with wlroots, which uses only
EGLImageKHR and never uses
Clients create an
EGLImageKHR with the target
EGL_HOST_POINTER_MESA, and a pointer to the chunk of memory in
buffer. Width, height, stride and format are provided as attributes.
Is this an acceptable approach?