Subdivison Surface Modifier / UV islands boundary Problem I have some subdivision + UV boundary problem
My English is poor. So I prepare image


As  you see the picture
The Blender's result of UV islands boundaries are different with other DCC, after subdivision
I think my blender "smooth, keep corners" option didn't work properly
I need the same Result, Like Maya and 3Ds Max

I use blender for modeling and Texture painting
But I cannot do texture paint with This kind of UV islands boundary result to export to other DCC
Please!! Help me!!

Thanks!!
to get the same result as Maya/3DS Max, follow these steps:


apply SubSurf modifier with Sharp option instead of Smooth, keep corners


your uv layout will be changed into this (notice the sharp borders)


select uv's borders and pin them (press P key), so those vertices will keep the position in the uv-space (pinned vertices are red)


select all vertices (in the uv editor) and press U to update all the other vertices - you should get this result