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ackees
05-20-2006, 05:40 AM
Hi,
Is there a way to save an existing UV map with textures applied to another UV map including the mapped texture for editing?
Basically:
I have a hat with several UV's
and several pieces of texture that join up to make the fully textured hat.
I would like to group all these UV's into one UV and re-export as a single globe UV, and also export the textures joined for this export UV, then I can go in and smooth the joins.
Thanks in advance.

oDDity
05-20-2006, 08:22 AM
You can manually place the separate UVs into a single UV map by usiing the copy UVs command, but you can't use LW to merge your separate image maps together, you'll have to take a screengrab of the merged UV map and photofit your separate textures to match it in photoshop.

ackees
05-20-2006, 05:01 PM
Thanks oDDity,
What you have suggested would be like sleeping on a bed of nails for me, I am surprised that NT have not thought we might need such a feature (or maybe it's too difficult for the programmers).

DonS
05-20-2006, 08:30 PM
Actually, you can do this directly in LW and it's not very difficult. First, generate a new UV map for the entire object; an Atlas will do fine though you may want to optimize it a bit to most effectively utilize the UV space. Leave your existing UV maps alone for the time being. Next, go into Layout and apply Surface Baker to one of your surface (doesn't matter which). When looking at Baker's interface, you'll likely want to leave"Bake Color" checked and uncheck the 2 boxes below it (unless you want those channels included). For the "UV Map" drop down, use the new map you created in the first step. Next, pick your resolution and select your "Image Type". Lastly, pick a name for your integrated texture and check the boxes for antialiasing and shading noise reduction. Hit F9 and wait for LW to generate your new map. When it's complete, go back through the surfaces of the model and change the UV map from the ones you started out with to the new Atlas and change all the textures to the baked image.

Basically, what you're doing is letting LW bake your old textures into a single new one which uses a single UV map. I've done this plenty of times and it works perfectly. Best part is that, after it's done, there's no fiddling around or seams to smooth out; Baker makes the old textures fit precisely into the new texture...which is matched perfectly to the new UV map.

Hope this helps!

D.

ackees
05-21-2006, 01:11 AM
Wow Dons!
I am going to have a go and let you know how it went.

oDDity
05-21-2006, 01:54 AM
I knew surface baker could do that, but I thought it would leave your images with shadows and highlights on it, but I suppose if you set all the sufaces to 100% luminosity and 0% diffuse the lights won't affect it.
That's useful to know.

DonS
05-21-2006, 04:40 AM
ackees: it should work out fine as I've done it for exactly the reason you specify. Tried it first when, after building a model for a client, there was a "requirement change"....I had painted about 70 textures for a model and the client tells me (after delivery) that they want a maximum of 6 textures. Thought about it for a bit and tried this. Huge sigh relief when it worked.

ODDity: that's why I was afraid it wouldn't work the first time out...but if you uncheck the "Illumination" box, the rendered texture will come out with no lighting effects applied...think of it as if you'd used purely 100% ambient lighting in the scene. Added luminosity won't be needed. In fact, some of the surfaces on the objects I've done this with have had >0 luminosity settings and the bake doesn't show any difference in these areas...just what I wanted as I simply needed the Color channel information in the texture.

D.

ackees
05-24-2006, 01:52 AM
Hats off to you DonS,
This is a great technique. For those wanting to try it remember that you have to turn off multi-threading (hope that's fixed in 9). I did notice that when you remap the texture to the new UV the texture changes (stretches in a different way).

DonS
05-24-2006, 10:52 AM
8^)

It stretched on the UV map or on the object? Hmm, when I've done this I expect to see differences in the various parts of the texture as they appear in the baked UV image when compared to the original individual textures...but these distortions should be limited to the UV image alone and not apply to the appearance of the object.

FYI, to avoid stretching, I almost always use the GreatBox plugin when doing UV mapping. As you're adding various bits of geometry to a UV map, GreatBox will keep these additions properly sized, relative to XYZ coordinates. In other words, geometry won't be stretched to fill the entirety of the UV space when an auto-UV mapping scheme is used; it'll keep the original shape.

D.

mdunakin
07-25-2006, 06:27 PM
Dons, you rock! ! ! ! ! !

I will be trying this out as soon as I can get back into LW.
Right now though, for some strange reason, my LW9, Layout AND Modeler, won't run anymore!
Grrrrrrrrrrrrrr! ! ! ! !

Everything was running just fine before, so I have no clue why things stopped working now?

..................md