Native bindings to the EXT_pvrtc_sRGB extension.

The response from electronic display systems given RGB tristimulus values for each pixel is non-linear. Gamma correction is the process of encoding or decoding images in a manner that will correct for non-linear response profiles of output devices. The displayed results of gamma-corrected pixel data are more consistent and predictable for the author of such pixel data than it would otherwise be with linearly encoded pixel data.

This EXT_pvrtc_sRGB extension specifies additional tokens for gamma corrected PVRTC compressed sRGB data.

Texture assets are developed and evaluated for use in OpenGL applications using electronic displays with non-linear responses. This extension provides a better measure of consistency between textures developed within an asset toolchain and their final rendered result with an OpenGL application that uses those textures.

Conventional OpenGL texture tristimulus values as well as their alpha component are encoded linearly. The textures introduced by this extension are encoded with gamma correction in the tristimulus components but linearly in the alpha component.

When gamma corrected texture samples are fetched and operated on by ALU operations in an OpenGL shading program those samples will be converted from gamma corrected space to linear space for logical simplicity and performance of the shader.

Texture filtering operations as well as mipmap generation are carried out in linear space.

Requires GLES 2.0 and IMG_texture_compression_pvrtc.