First of all - thanks to you
I didnt even know that there was a 2D line function, that gave me an idea - using a 2D only solution (as Joozey suggested), with an 3D-array based level, and drawing the outlines based on the surrounding blocks myself.
Of course a 3D Version would be easier for the movement/collision etc, but upscaling and the "which vertex must connect to another" thing seems to be more work.Ahh, fu, that wont work as expected... Need to think about something else D:
Still, thank you!