Becauseā¦ reasons. (How my daughter answers questions.)
At [url]http://mathhombre.tumblr.com/post/131821215449/grid-deformations-because-reasons-how-my[/url]
I have several examples. I like odd function visualizations. First couple I show have y-matters on vertical endpoints and x on horizontal, then I played with mixing and breaking symmetry.
[url]mathjax.tumblr.com[/url] requested the source, so here it is!