GL_EXT_point_parameters
http://oss.sgi.com/projects/ogl-sample/registry/EXT/point_parameters.txt
	GL_POINT_SIZE_MIN_EXT 0x8126
	GL_POINT_SIZE_MAX_EXT 0x8127
	GL_POINT_FADE_THRESHOLD_SIZE_EXT 0x8128
	GL_DISTANCE_ATTENUATION_EXT 0x8129
	void glPointParameterfEXT (GLenum pname, GLfloat param)
	void glPointParameterfvEXT (GLenum pname, GLfloat* params)