Does the spinning cube have the dots spaced by perspective, as stars would be? Anyway.
Was about to edit my post and say I was fooled by the ascii graphics. Yes, setting the conditional shifting in the mask and copying is possible (without extra blits if abs(dy)<=1). For the 3rd blit you'd replace the 0011 with 0000 to only shift the first sliver. If the curve is steep there might be icky things to solve near max and min curves, but it only takes aligning peaks to between 16px words to solve that, so it's a non-problem.
Last edited by Photon; 27 January 2012 at 23:56.