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Does anyone have any ideas why this face is always so warped in the UV map? Even if I run a seam on every edge, it appears warped on the UV map. The opposite face of the same shape shows fine.

Blender 2.72, 32 bit, Windows 7.

Blender Screen Shot

Blender Screen Shot

David
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John
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  • The problem seems to be that it is an n-gon, blender doesn't deal very well with n-gons, even if they are as simple as this. I would recommend deleting the face ([Delete] > faces), selecting the edge loop around where the face should be, and using grid fill by pressing [space] and typing "grid fill". You can then hit [F6] and adjust the settings. – PGmath Nov 27 '14 at 00:45

2 Answers2

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Ngons tend to cause problems for the UV Unwrap algorithm. Not always but often enough, it seems random which ones will work and which ones won't.

You can deal with that particular case by pressing Shift+7 on the number pad so the view aligns with that selected faces normal then press u to bring up the Unwrap menu and then select Project from View

Now the shape should now perfectly match the face. You'll still likely have to resize it though.

MarcClintDion
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Ngon currently doesn't work pretty well with seamed unrapping, so it would be recommended to unwrap UV as early as you can. However, you can consider to unwrap after splitting ngons, then disolve ngons again.

  1. Select all ngon faces, CtrlT to trianglate;
  2. Select all, unwrap again;
  3. If the result is expected, then X -> Limited Dissolve to convert them back to ngons (if needed).

enter image description here

Tip: For more generic cases other than this model, it is highly recommended to triangulate ngons (faces with more than four sides) only, not existing quads, since topology could be likely changed after dissloving. So it is recommended to use menu Select > Select Faces by Sides, then select faces with sides number greater than 4.

enter image description here

Leon Cheung
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  • Thank you both... I thought I had tried this already, but this time it seems to have worked. Perhaps I forgot to actually re-unwrap last time. Perfect now. – John Dec 01 '14 at 17:46