OpenGL is a standard API for 3D rendering, which is provided by Haiku and many other operating systems and libraries.

EGL complements OpenGL with a way to open and manage GL contexts (usually rendering windows). It is a cross-platform equivalent to GLX.

The current Mesa port for Haiku does not implement EGL, which makes it impossible to run EGL based applications.

Implement the required parts in Mesa so the EGL support can be enabled and these applications can be ported.