Implies no preference for which backend is used
Use EGL with the Android platform
Use EGL with the GDL platform
Use EGL with the KMS platform
Use EGL with the Mir server
Use EGL with the PowerVR NULL window system
Use EGL with the Wayland window system
Use EGL with the X window system via XLib
Use the GLX window system binding API
Use the SDL window system
Use the no-op stub backend
Use the Microsoft Windows WGL binding API
Identifies specific window system backends that Cogl supports.
These can be used to query what backend Cogl is using or to try and explicitly select a backend to use.