GLX_SGIX_fbconfig
https://www.khronos.org/registry/egl/specs/eglspec.1.5.pdf
GLX_SGIX_fbconfig

	GLX_WINDOW_BIT_SGIX 0x00000001
	GLX_RGBA_BIT_SGIX 0x00000001
	GLX_PIXMAP_BIT_SGIX 0x00000002
	GLX_COLOR_INDEX_BIT_SGIX 0x00000002
	GLX_SCREEN_EXT 0x800C
	GLX_DRAWABLE_TYPE_SGIX 0x8010
	GLX_RENDER_TYPE_SGIX 0x8011
	GLX_X_RENDERABLE_SGIX 0x8012
	GLX_FBCONFIG_ID_SGIX 0x8013
	GLX_RGBA_TYPE_SGIX 0x8014
	GLX_COLOR_INDEX_TYPE_SGIX 0x8015
	GLXFBConfigSGIX* glXChooseFBConfigSGIX (Display* dpy, int screen, int* attrib_list, int* nelements)
	GLXContext glXCreateContextWithConfigSGIX (Display* dpy, GLXFBConfigSGIX config, int render_type, GLXContext share_list, Bool direct)
	GLXPixmap glXCreateGLXPixmapWithConfigSGIX (Display* dpy, GLXFBConfigSGIX config, Pixmap pixmap)
	int glXGetFBConfigAttribSGIX (Display* dpy, GLXFBConfigSGIX config, int attribute, int* value)
	GLXFBConfigSGIX glXGetFBConfigFromVisualSGIX (Display* dpy, XVisualInfo* vis)
	XVisualInfo* glXGetVisualFromFBConfigSGIX (Display* dpy, GLXFBConfigSGIX config)
	typedef XID GLXFBConfigIDSGIX
	typedef struct __GLXFBConfigRec *GLXFBConfigSGIX