Chris Plush writes:
We’ve all been there. You’re using the subsurf modifier for hard surface modeling then you go to add details to a curved surface and it ruins everything by distorting the curvature. Some people call this creasing, or pinching, but whatever you call it it’s probably the most common and most annoying issue among subsurf modelers. In this tutorial I’m going to show you an advanced technique to achieve perfect curvatures while also improving your workflow speed. And it’s all done with the magical shrinkwrap modifier. Car model courtesy of lubomircenovsky on blendswap.