# Prepare all attributes once per resolution change
	fun prepare_once(display: GamnitDisplay, max_dynamic_resolution_ratio: Float)
	do
		# TODO enable antialiasing.

		# Framebuffer
		var framebuffer = glGenFramebuffers(1).first
		glBindFramebuffer(gl_FRAMEBUFFER, framebuffer)
		assert glIsFramebuffer(framebuffer)
		self.dynamic_framebuffer = framebuffer
		assert glGetError == gl_NO_ERROR

		# Depth & texture/color
		var depthbuffer = glGenRenderbuffers(1).first
		self.depth_renderbuffer = depthbuffer
		var texture = glGenTextures(1).first
		self.texture = texture
		assert glGetError == gl_NO_ERROR

		resize(display, max_dynamic_resolution_ratio)
		assert glCheckFramebufferStatus(gl_FRAMEBUFFER) == gl_FRAMEBUFFER_COMPLETE

		# Array buffer
		buffer_array = glGenBuffers(1).first
		glBindBuffer(gl_ARRAY_BUFFER, buffer_array)
		assert glIsBuffer(buffer_array)
		assert glGetError == gl_NO_ERROR

		## coord
		var data = new Array[Float]
		data.add_all([-1.0, -1.0, 0.0,
	                   1.0, -1.0, 0.0,
	                  -1.0,  1.0, 0.0,
	                   1.0,  1.0, 0.0])
		## tex_coord
		data.add_all([0.0, 0.0,
		              1.0, 0.0,
		              0.0, 1.0,
		              1.0, 1.0])
		var c_data = new GLfloatArray.from(data)
		glBufferData(gl_ARRAY_BUFFER, data.length*4, c_data.native_array, gl_STATIC_DRAW)

		glBindBuffer(gl_ARRAY_BUFFER, 0)

		assert glGetError == gl_NO_ERROR
	end