Interesting Tile-Like Surface!
![Image](https://beta.geogebra.org/resource/p3buh3nd/RQmJ1OcVGWvzsTNL/material-p3buh3nd.png)
Here, we have 2 surfaces that nicely merge into one.
The cross section of this surface and ANY PLANE parallel to z = x or z = -x are cosine waves with amplitude = 0.5 and period = .
And yes, we DO see LOTS OF SQUARES here. Why?