Drawing on planar surface is very good, I just have habit to set Cplane and open it in TOP view, It looks for me more convinietn to draw, that is why I asked for simple script to set Cplane and the tourn on TOP view. But I can also dray in 3D view on surface. Everything is already good drawing on surface. But when you have to draw on non planar surface or on 2 non planar surfaces and then project it. I use Cplane and set Cplane from view.