GL_IMG_multisampled_render_to_texture
https://www.khronos.org/registry/OpenGL/extensions/IMG/IMG_multisampled_render_to_texture.txt
GL_IMG_multisampled_render_to_texture

	GL_RENDERBUFFER_SAMPLES_IMG 0x9133
	GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE_IMG 0x9134
	GL_MAX_SAMPLES_IMG 0x9135
	GL_TEXTURE_SAMPLES_IMG 0x9136
	void glFramebufferTexture2DMultisampleIMG (GLenum target, GLenum attachment, GLenum textarget, GLuint texture, GLint level, GLsizei samples)
	void glRenderbufferStorageMultisampleIMG (GLenum target, GLsizei samples, GLenum internalformat, GLsizei width, GLsizei height)