Subdivision Surface question (sharp corner at vertex) - Illustrations included

Hello everyone,

I am encountering an question and issue when modeling subdivision surfaces in Blender when I want there to be a sharp corner at a vertex. From what I recall, I could do this in Cinema 4D fairly straightforwardly by weighting a vertex. However, in Blender it seams that one can weight a “crease” but I don’t see how to weight a vertex. To me, this seems like something that an amazing program like Blender should be able to do, so hopefully I am just missing something. Here are some illustrations to show what I mean:

Illustration A shows a bunch of polygons with a subdivision surface modifier applied. Note that all corners and creases are subdivided and smoothed out.

Illustration B shows the same shape, only on two of its edges the edge creasing weight has been changed from 0 to 1. This results in a sharp edge crease at those edges. That is useful for some things I suppose, but that is not what I am looking to do.

Illustration C shows more what needs to be done. At point 1, I want the subdivision surface to come to a sharp corner (along the red lines). In other words, I do not want the corner to be curved as is there now. I don’t want any edges to be creased either.

Is there a way to keep all subdivisions on the shape except be able to weight that vertex (1) so it comes to a sharp corner at that point? I really need a sharp corner at that point.

Thank you ever so much in advance for your help.

You have to crease the edges around the corners you want sharp:

Hi. Thank you for your help. Unfortunately that doesn’t solve the problem. It may work on outside corners, but not on the corner in picture C which is different (and the kind of corner in my model).

If you try your message on the inside corner, as in picture C, you will see that it does not work. Can you (or anyone else on this forum) think of another way to weight that point so that corner becomes sharp?

Thank you!

By the way, the outside corners, as in your diagram, can be easily sharpened by clicking on “Keep Corners” in the Subdivision Surfaces modifier without having to use edge creases.

Developers say that most if not all edges that lead to a vertex must have a crease to have the vertex sharp. So you have to do it like this:

It’s kinda messy to work with creases, so many prefer to use loop cuts instead (create another edge close to an existing one to force the subdivision surface to work as wanted).

Sharp and Smooth, keep corners are options only for the UV, they don’t affect the geometry, at least not in my version of Blender.

Thank you but I need to do it without creasing a whole edge, since I don’t want the entire edge to be creased (just the point). I guess there is no real way to do it. That is too bad.

By the way, yes there is a Keep Corners option both for UV and Boundry in the sub surf modifier. Check it out under Advanced. You’ll see it there.