Clippath

As i discovered previously in CSS Secrets, clip paths can be animated. This is really cool, though practically only when we define them as a polygon, hence they have to be edgey shapes. (or do they?) - still we can achieve some nice effects with this

just make the normal square rotate its corners around

edge-y shapes work great

But we can make nice curtain effects, here's one i made earlier

Double curtain??

For example I recently saw a nice use of this as a shifting polygon

If we are just cliping a rectangular cutout we can use 'inset' which also allows us to use 'rounded' for corner radi

which we can use to go from square to round

ok one more, circle is a little boring to play with, but there is an ellipse so we can