Rotation about the origin is equivalent to the matrix [cos(a) sin(a) -sin(a) cos(a) 0 0], which has the effect of rotating the coordinate system axes by angle 'a'. The test overlays a group of black graphics elements with a 'rotate' transform specified on top of an identical group of red elements with the equivalent 'matrix' transform and vice versa.
Run the test. No interaction required.
Test passes if there is no red visible on the page.