Sub-Nested Quilt Tiling

If you pay attention to the ratios when stacking quilt tiling patterns you can generate some really interesting patterning. This is using a 1-3-9 nesting grid for the 3 nine block overlays.

If you look closely, there's a slight issue with the region seams because the top overlay has a pen size of 0. Note to self that I should modify the controls to make it easy to default to region color and size of 1 if you don't want colored pattern edges.