GL_SGIS_detail_texture
https://www.khronos.org/registry/OpenGL/extensions/SGIS/SGIS_detail_texture.txt
GL_SGIS_detail_texture

	void glDetailTexFuncSGIS (GLenum target, GLsizei n, const GLfloat* points)
	void glGetDetailTexFuncSGIS (GLenum target, GLfloat* points)