GL_REGAL_enable https://github.com/p3/regal/blob/master/doc/extensions/GL_REGAL_enable.txt GL_REGAL_enable GL_ERROR_REGAL 0x9322 GL_DEBUG_REGAL 0x9323 GL_LOG_REGAL 0x9324 GL_EMULATION_REGAL 0x9325 GL_LOADER_REGAL 0x9326