I am trying to cut the profile of my reference using clipcurve but i get these straight lines and spikes which seems like a bug. Am i doing something wrong?
Disable perspective, keep a front view to the model and have a clean finely divided geometry (dynamesh for example)
But if when doing the curves you see the shadow of the curves start to cross the line, then those straight lines will appear. It is a limitation of the tool. It only admits certain wide angles in the curves. You could try booleans or if you don’t mind to be a less precise shadowbox.