Thank you Kizza,
the problem I see is that I have always more than one geometry and a lot of work.
1. Drawing in 3d,
2. Extract,
3. Convert to 2d polygon,
4. Hatch (or the other way round)
So if I draw in 3d geometry and change something, I have to do the same procedure again and I always have more than one geometry for the same thing.
Maybe I missed sth.