There are a few things you could do:
- You could use view() to modify the viewing angle of the graph on the left. If you only plot the points at the particular cross section and find the correct viewing angle, it should show those points.
- If you know how the plane is defined, you can mathematically transform your points into whatever x-y coordinate system you need for the image on the right.
If you share some specific code it might be helpful.
