public Class EXTShaderFramebufferFetchNonCoherent

Specifies a boundary between passes when reading existing framebuffer data from fragment shaders via the gl_LastFragData built-in variable. Previous framebuffer object writes regardless of the mechanism (including clears, blits and primitive rendering) are guaranteed to be visible to subsequent fragment shader invocations that read from the framebuffer once FramebufferFetchBarrierEXT is executed.

If EXT_shader_framebuffer_fetch is also supported: Because the implementation guarantees coherency of framebuffer reads and writes for color outputs not explicitly marked with the noncoherent layout qualifier, calling the FramebufferFetchBarrierEXT command is not required unless the application wishes to manage memory ordering of framebuffer reads and writes explicitly, which may provide better performance on some implementations in cases where rendering can be split into multiple passes with non-self-overlapping geometry.