Libgbm

This is the gbm frontend used by (for example) weston compositor to load the GLES stack, and retrieve the backing buffer objects behind an eglImage (created with EGL_WAYLAND_BUFFER_WL), etc.

The frontend is really just a backend loader and shim. The backend library must be provided by the GLES implementation.

To get wayland up and running on your GLES stack:

1. implement gbm backend
2. implement EGL_WL_bind_wayland_display extension (including EGL_WAYLAND_BUFFER_WL eglCreateImageKHR target for compositor-drm it looks like we also need EGL_KHR_surfaceless_gles2 extension..

<robclark> hmm, I don't suppose there is any extension description for EGL_KHR_surfaceless_gles2 ? <pq> robclark, it should simply mean you can eglMakeCurrent with NULL surface, but a real context.

3. implement wayland-egl (must provide wayland-egl.pc)
4. ???
5. PROFIT!!

need this in your eglext.h:

#ifndef EGL_WL_bind_wayland_display #define EGL_WL_bind_wayland_display 1

#define EGL_WAYLAND_BUFFER_WL 0x31D5 /* eglCreateImageKHR target */ struct wl_display; #ifdef EGL_EGLEXT_PROTOTYPES EGLAPI EGLBoolean EGLAPIENTRY eglBindWaylandDisplayWL(EGLDisplay dpy, struct wl_display *display); EGLAPI EGLBoolean EGLAPIENTRY eglUnbindWaylandDisplayWL(EGLDisplay dpy, struct wl_display *display); #endif typedef EGLBoolean (EGLAPIENTRYP PFNEGLBINDWAYLANDDISPLAYWL) (EGLDisplay dpy, struct wl_display *display); typedef EGLBoolean (EGLAPIENTRYP PFNEGLUNBINDWAYLANDDISPLAYWL) (EGLDisplay dpy, struct wl_display *display); #endif