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Quoll
02-22-2003, 02:48 PM
Hiya

I am using Lightwave 7.5 and want to flip UV's. It's easy enough to do this using the "flip uv's" command but that mirrors the UV shape. What I want to do is flip the direction the UV's face but leave the shapes as they are. Is there any way to do this in LW 7.5? I would even settle for a plug in (Mac Compatable).

I want to do this to preserve the flat distortion free mapping I acheive using Atlas, but then be able to sew certain parts back together to make a better map for texture painting. Mirroring the UV polygon shapes throws the whole thing out of whack. Or am I just being stupid and only the preview is reversed?

Thanks!

Thanks for any help anyone!

Lynx3d
02-23-2003, 09:25 AM
Originally posted by Quoll
What I want to do is flip the direction the UV's face but leave the shapes as they are.

Huh? Maybe you explain a bit more precise (an image would possibly help)
To me it sounds like "i want to flip without flip" but that's an antilogy...

I don't know what you mean with direction, UVs are just 2-dimensional coordinates, i don't see any direction there you could flip.

Quoll
02-23-2003, 12:24 PM
Wow! Ok, I just found what is either a bug or a "feature". ; )

Here is what I did before. Load the model I want to map and apply an image in the color channel. The image is a grid of different colored squares with a number in each one. I use it for mapping so I can see the results of edits to the UV Map live. As long as this texture looks right on the model I know any maps I make will like right as well. A great way to eliminate distortion.

Ok, next step is to create an atlas map for the object. This gives me some nice big chunks that are already distortion free (usually). Then I arrange the parts into a set of recognizable shapes that will make it easy to paint textures on. When I do the atlas map about half of the parts will display the surface image inverted, usually along the U axis. In other UV editors I have used this means that the texture in that area will appear mirrored. So I was trying to find a way to "flip" those UV's, but using the flip command in Lightwave actually mirrors the shape along the U or V axis. This is not at all appropriate because then the shapes dont fit together anymore and it becomes next to impossible to texture correctly. For example, if you "flip" the left side of a shirt it will look like the right side. Not good.

Anyhow, after fiddling with that for a while I closed the model and decided to try again later. I opened it up just now to do a screen shot to show you, and the surface texture is now applied correctly around the entire model! So, I can only assume that Lightwave doesn't update the projection of the surface after it creates an atlas map and thus some surfaces will appear inverted.

Wierd. I'm going to go ahead and finish the mapping for this model and apply a texture to make sure that what I think is happening is indeed the case. If so it is a bug that should be easy to live with. I was thrown off because in BodyPaint 3D and UVMapper a user can actually flip the polygons without the uv polygons actually inverting.

Thanks!