I have a mesh with a subsurf modifier on. I do want to use Catmull-Clark, and I do want the internal UV vertices to be subdivided–just not the ones on the very edge of my UV islands. Is there any way to keep those borders from changing position when applying the modifier? To lock them in place?
I tried pinning, but that didn’t work, they still moved.
I don’t know, try to crease those edges that you don’t want to move or change shape. You can crease them by going into edit mode selecting a face, edge or vertices and pressing Shift+E or Ctr + E -> “Edge Crease”.
You can have more than one copy of the object that uses the same uv map, you might be able to work a workaround with that, otherwise I need a picture to see what you mean fully.
Ok here are some pictures. So I have the uv’s laid out on this cylinder object.
This picture here shows the highlighted vertices that I want to keep right in that position:
But, I need to apply the subsurface modifier, and when I do, those vertices “smooth” out, just like the mesh does, so they do not keep their position:
I know that I can check “simple” or uncheck subdivide UV’s, however I want the rest of the uv’s to subdivide and smooth out, just not those particular ones(the ones at the edge).
Pinning didn’t help, creasing didn’t help either.
I just want to know what is the purpose of this, I’m really curious?
I’m making models that need to use approximately the same UV maps, that way they can swap textures and it will work on each model. It’s ok for them to change a bit internally and be subdivided, but the edges are the most important to stay the same. So I’m having to manually edit those vertices back into place after I subdivide my mesh(and uv’s) so was hoping there’s a way to keep the ones I want in place.
Let me give you a honest advice here, I think you should thoroughly investigate and learn about UV unwrapping in Blender before going any further. And then you’ll have all the needed knowledge that will allow you to UV unwrap all objects the same/similar way.
I know all about UV unwrapping. I’ve been making models and texturing/uving them for years. I was just looking for an automated solution to this, if there is one.
Have you tried switching on and off ‘Use Subsurf Modifier’ in the ‘T’ panel when unwrapping (in the 3D viewport)?
When you go unwrap, press ‘U’ and ‘Unwrap’ as usual, then it’s at the bottom.
I have the same problem.
In Arnold, subdivision is adaptive.
Which means subdivision level changes according to the screen resolution.
If the vertices position of the UV borders changes when subdivided, the borders do not much with the texture.
The same thing happens in UE4 and other applications.
I think that is why Maya, Zbrusn, 3D-coat, etc can keep the borders when polygon mesh is subdivided.
