GL_ARB_sample_shading
https://www.khronos.org/registry/OpenGL/extensions/ARB/ARB_sample_shading.txt
GL_ARB_sample_shading

	GL_SAMPLE_SHADING_ARB 0x8C36
	GL_MIN_SAMPLE_SHADING_VALUE_ARB 0x8C37
	void glMinSampleShadingARB (GLclampf value)
