Native bindings to the APPLE_framebuffer_multisample extension.

This extension extends the framebuffer object framework to enable multisample rendering.

The new operation RenderbufferStorageMultisampleAPPLE() allocates storage for a renderbuffer object that can be used as a multisample buffer. A multisample render buffer image differs from a single-sample render buffer image in that a multisample image has a number of SAMPLES that is greater than zero. No method is provided for creating multisample texture images.

All of the framebuffer-attachable images attached to a framebuffer object must have the same number of SAMPLES or else the framebuffer object is not "framebuffer complete". If a framebuffer object with multisample attachments is "framebuffer complete", then the framebuffer object behaves as if SAMPLE_BUFFERS is one.

The resolve operation is affected by calling ResolveMultisampleFramebufferAPPLE where the source is a multisample application-created framebuffer object and the destination is a single-sample framebuffer object. Separate read and draw framebuffer object binding points are established to facilitate the resolve.

Scissoring may be used in conjunction with ResolveMultisampleFramebufferAPPLE to resolve only a portion of the framebuffer.

Requires GLES 2.0.