Why stop at a rectangle when the same method can be used to draw animated lines in any angle? So here is a Marching Ants Path class - I don’t know if it’s of any use - maybe for a lasso tool of some upcoming Flash based “Photoshop Junior” RIA?

BTW - the hardest part was to make the bitmaps line up correctly so that the patterns are moving somehow in sync. There is some under-the-hood stuff going on with beginBitmapFill that I haven’t yet fully figured out. It seems like the fill bitmaps get aligned to 0/0, but when they are flipped they don’t. Or do they?

Whatever, the current version uses a mixture of try-and-error plus in-theory-this-should-work algorithms and funny enough this seems to work well with short, curvy pathes and a little less well with long straight line segments. But you can see that anyway only with the “long” setting in the demo.