Mesh Weld Mapping Problem

I ran into a problem with a mesh. When it is welded, it maps correctly, however as soon as i meld the vertices together material maps wrong.

for more understanding of the problem:

I think you’re welding the verts so you can edit the mesh without pulling the edges apart. If that’s the reason, I would instead use sub-object modeling by clicking the corner with ctrl and shift held down. Then move that point around with the Gumball and you won’t have to use WeldVertices.

I don’t know if WeldVertices and texture mapping are working as designed or if it should be possible to both weld and preserve the texture space. @andy may be able to offer more here.

Hi Brian, Your proposal of using sub-object modeling works, however it seems to me like a quite big bug that you cannot weld vertices and have proper mapping at the same time! I am using Vray so perhaps it is their issue, I will aks them too and keep you updated

this seems to be a general rhino bug as it doesn’t work with vray default renderer either.