Hi @kacperpach42,
Here is a cheap sample that produces this:
The magic is setting mesh vertex colors so as to provide a “false color” appearance.
I reverted to using some C# code because I am lame a Grasshopper. But hopefully this will move you forward. The code uses the Z-coordinate of mesh vertices to cook up a color in a range.
test_false_color.gh (32.0 KB)
Hope this helps.
– Dale