This demo requires HTML5 Canvas support.

This page animates the usual deformation retraction of the plane to a point—as the time $$t$$ goes from $$0$$ to $$1$$, each point of the plane moves in a straight line at constant speed to $$(0,0)$$. In symbols:

$(x, y, t) \mapsto ((1-t)x, (1-t)y)$

People only sometimes point out how weird this is. As long as $$t \neq 1$$, the whole plane is still the whole plane—but when $$t = 1$$ everything is suddenly mashed down to a point.

Just for kicks, it also plays backwards.

Code written by Pteromys and released under the Unlicense.