GL_INTEL_map_texture
http://www.opengl.org/registry/specs/gl/INTEL/map_texture.txt
GL_INTEL_map_texture
	GL_LAYOUT_DEFAULT_INTEL 0
	GL_LAYOUT_LINEAR_INTEL 1
	GL_LAYOUT_LINEAR_CPU_CACHED_INTEL 2
	GL_TEXTURE_MEMORY_LAYOUT_INTEL 0x83FF
	GLvoid * glMapTexture2DINTEL (GLuint texture, GLint level, GLbitfield access, GLint* stride, GLenum *layout)
	void glSyncTextureINTEL (GLuint texture)
	void glUnmapTexture2DINTEL (GLuint texture, GLint level)