Evaluate the possibility of implementing X11 EGL support for Raspberry Pi

[ssvb]

It might be nice to support a standard API for better compatibility with the existing applications. Currently the Raspberry Pi folks are littering free software by pushing the DispmanX hacks everywhere.

PS. Wayland EGL is another alternative for the future standard common ground, but that's out of scope of the Xorg DDX driver.

[kika123]

Here:
https://github.com/kika123/x11eglrpi.git

I've half-written an X11 EGL implementation, which works with OpenGL Programming Guide book samples.

[kika123]

This implementation works with APKENV !!

Need just to reimplement eglGetAttrib.

[ssvb]

@kika123 Yes, it is always possible to do the 3D rendering entirely on the client side and then use the standard X11 API to move it to the screen. No support in the DDX driver is required for this approach at all. However the price is an extra expensive copy of the image buffer.

This ticket is actually about implementing zero-copy X11 EGL with the use of DRI.