GL_EXT_texture_compression_astc_decode_mode_rgb9e5
https://www.khronos.org/registry/OpenGL/extensions/EXT/EXT_texture_compression_astc_decode_mode.txt
GL_EXT_texture_compression_astc_decode_mode_rgb9e5

	GL_TEXTURE_ASTC_DECODE_PRECISION_EXT 0x8F69