GL_EXT_EGL_image_storage_compression https://www.khronos.org/registry/OpenGL/extensions/EXT/EXT_EGL_image_storage_compression.txt GL_EXT_EGL_image_storage_compression GL_SURFACE_COMPRESSION_EXT 0x96C0 GL_SURFACE_COMPRESSION_FIXED_RATE_NONE_EXT 0x96C1 GL_SURFACE_COMPRESSION_FIXED_RATE_DEFAULT_EXT 0x96C2