Why is the Decimate modifier removing my UV's?

I’m making a game with blender, and am working on a barn. I try to decimate and it erases my UV’s, which the entire mesh is made out of. I’ve spent like 5 hours on this. Can someone please tell me how to save my UV’s? Or maybe save all the UV’s as a new one then unwrap again somehow?
Thanks in advance

Why is the Decimate modifier removing my UV’s?
Because it does, there is no way around this using the decimate modifier.
You’ll have to uv unwrap again after you have reduced the poly count either using the modifier or manually. If your original high res mesh has textures then just save a copy of it, uv unwrap your low res model and bake the texture from the high res to the low poly uvs. You can do this from the Render / Bake panel.
If you don’t want to do this then you can use the Poly Reducer script in blender 2.49 which reduces the poly count and tries to maintain your uvs.
If you don’t want to use the decimate modifier you could also look at other poly reducers such as Meshlab or Reducto

EDIT: Please post support questions in the support forums, not in the Discussion forum.

slow as it was it’s probably worth a port to current blender…

Ive spent about 5 hours making a barn for a game. Turns out my poly count is 953 and it has to be decimated, however, there are 2 issues.

  1. Decimate removes my uv textures which was 4 and a half hours of my 5 hours of construction.
  2. Decimate seems to not work at random times and i get the error message:
    Non-manifold mesh as input.
    I don’t know what that means or how to fix it.
    Any help would be greatly appreciated. Thank-you in advance.

Thanks and sorry. I just joined and didnt read…

Hi there,

First off, except in very rare cases, I recommend never using the Decimate modifier. When working with low resolution objects you want to have absolute control over your mesh. The decimate modifier doesn’t give you this. Also, as you’ve found it’s destructive to your UVs.

I recommend going through and manually removing edges bit by bit to reach the desired polycount. If you use the Dissolve function in Blender 2.63+ then it should maintain your UVs.

  1. Decimate seems to not work at random times and i get the error message:
    Non-manifold mesh as input.
    A non manifold edge is http://www.rhino3d.com/5/help/popup_moreinformation/non-manifold_edges.htm so as the error message says, you’ll have to fix your mesh to remove them. To see where they are in Edit mode use the Select / No Manifold menu entry
    Given your poly count is only 953 you should easily be able to reduce than manually to give a better result than the modifier

Thanks and I’ve found all of your video’s helpful.