# Create an orthogonal projection matrix
	#
	# `left, right, bottom, top, near, far` defines the world clip planes.
	new orthogonal(left, right, bottom, top, near, far: Float)
	do
		var dx = right - left
		var dy = top - bottom
		var dz = far - near

		assert dx != 0.0 and dy != 0.0 and dz != 0.0

		var mat = new Matrix.identity(4)
		mat[0, 0] = 2.0 / dx
		mat[3, 0] = -(right + left) / dx
		mat[1, 1] = 2.0 / dy
		mat[3, 1] = -(top + bottom) / dy
		mat[2, 2] = 2.0 / dz
		mat[3, 2] = -(near + far) / dz
		return mat
	end