Straighten UV Border is useful when you want to untangle the border of a UV shell, such when the border edge loops around itself. Straighten UV Border provides more control than the Map UV Border operation.

To straighten border UVs

1. In the UV Texture Editor right-click and select UV from the marking menu.
2. Select the UVs around the tangled UV border.

   It doesn’t matter if you select interior UVs along with border UVs. Straighten UV Border only acts on the borders.

   In some cases, it is difficult to select the UVs you want to straighten without selecting other UVs you want to leave unaffected. In these cases, you can leave a gap in your selection and use the Fill Gaps in Selection option to straighten the UVs you could not select.

3. Select Edit UVs > Straighten UV Border.

   If you are using the UV Texture Editor, you can select Polygons > Straighten UV Border > .

4. Select the polyStraightenUVBorder node and edit the attributes in the Attribute Editor or Channel Box.