EXT_texture_compression_rgtc

readonly COMPRESSED_RED_GREEN_RGTC2_EXT: GLenum;

readonly COMPRESSED_RED_RGTC1_EXT: GLenum;

readonly COMPRESSED_SIGNED_RED_GREEN_RGTC2_EXT: GLenum;

readonly COMPRESSED_SIGNED_RED_RGTC1_EXT: GLenum;