GL_EXT_multisample
http://www.opengl.org/registry/specs/EXT/wgl_multisample.txt
GL_EXT_multisample
	GL_MULTISAMPLE_EXT 0x809D
	GL_SAMPLE_ALPHA_TO_MASK_EXT 0x809E
	GL_SAMPLE_ALPHA_TO_ONE_EXT 0x809F
	GL_SAMPLE_MASK_EXT 0x80A0
	GL_1PASS_EXT 0x80A1
	GL_2PASS_0_EXT 0x80A2
	GL_2PASS_1_EXT 0x80A3
	GL_4PASS_0_EXT 0x80A4
	GL_4PASS_1_EXT 0x80A5
	GL_4PASS_2_EXT 0x80A6
	GL_4PASS_3_EXT 0x80A7
	GL_SAMPLE_BUFFERS_EXT 0x80A8
	GL_SAMPLES_EXT 0x80A9
	GL_SAMPLE_MASK_VALUE_EXT 0x80AA
	GL_SAMPLE_MASK_INVERT_EXT 0x80AB
	GL_SAMPLE_PATTERN_EXT 0x80AC
	GL_MULTISAMPLE_BIT_EXT 0x20000000
	void glSampleMaskEXT (GLclampf value, GLboolean invert)
	void glSamplePatternEXT (GLenum pattern)