Question about smooth shading and geometry.

Hi there

even though I have been exploring Blender for a while now - and loving it! - I still don’t think I understand some of the basic principles.

I came across this problem yesterday and I don’t know how to solve it.

It is a curved wall with an arched window in it. The window is on the same plane, so not actually curved itself, but I get poor smooth shading on the top - outlined in red below. I have tried so many techniques to try to make it better - edge splits, sub surf, new topology etc. How can I solve this issue?

Any help would be great!


The Guerrilla CG project has a great video on smoothing artifacts that might help you understand what’s happening.

For this specific problem, I guess I’d just start with a lot more geometry like so:

It can be done pretty well with Sub D modelling. The trick is before deleting the polygons to inset them. Bang in a couple of Loop cuts and you’re done. This renders without any flat spots.