Question about textures

D4V1DC

Okay a client dropped the ball and I have to redo the textures to an arm of a character.

The question: is I already unwrapped and textured the arm, the problem is it was in parts so left side had a hand, right a bicep ect. scattered around the final unwrap texture map. (their was clothing removed) There has to be a way to reproject the first uv's texturing onto the 2nd uv's map right? Probably an old trick but I am at the point where I need that trick or a new solution to have less work to do.

So please anyone help so I can get some sleep tonight...

Rant:
I almost quit when he sent that e-mail...
Guess he didn't know about this situation and how problematic It can be so I will do It this one time, if this where on site I wouldn't care but It's not and It's getting late and he does this... Had to mention that final part so no body gets It twisted like I wouldn't do what I am told or whatever. Freelance is different from on site, on site you take it up the arse off site freelance some things you throw in the towel for.

I am not vastly knowledgeable like the rest of you so take It easy when you post a reply thinking that I should know these probably simple solutions already, I have to come across the problem in the first place to understand the solution or learn of one.

sprunghunt

render to texture can solve your problems. Make a copy of the mesh and change the UV's on the copy. Render from one mesh to another.

haikai

I'm not sure which app you're using, but this is also a pretty easy thing to fix in Maya with the Transfer Maps window. Load the original mesh as the source, and a new one with the correct UVs as the target and then transfer the diffuse information.

D4V1DC

3dsmax sry I didn't put that in their I always forget.

Sprung I did it with rtt but I got these dusty white marks all over my would be diffuse.
I decided to just do it all over again, but for the future I would like to know how to handle this in case it arises again. I know I need to use rtt now I have to know why I get those white dusty particle like sprays on my render?

Thanks guys either way, I wish I knew more about Maya Haikai, I don't even have time to sleep.

Ghostscape

drop an edit UV modifier on the mesh on channel 1, where your UVs are. Save out a copy of those UVs in case you fuck something up later.

drop a new one on, switch it to channel 2. I find it helps to load up the UVs you saved out from channel 1 so all you have to do is re-arrange islands
Re-unwrap it the way you want.

Make sure your material is assigned.
Fire up render to texture and select your mesh with 2 UVs.

Under the projection options, you want to use projection, but no modifier, and change the UVs for object to channel 2 and sub object to channel 1 (I think, I'm doing this off the cuff - if it is baking to the old UVs and looks wrong, then flip these)

Last time I tried this I had to swap my spec into my diffuse channel and render it out that way in two steps, because the way it renders the spec RTT isn't just copying the map.

But this will bake non-normal maps without requiring the projection.

If you want to bake normals I highly recommend going back to the high poly as you lose significant quality going from one normal map bake to a second normal map bake and it exacerbates any small errors.

Mark Dygert

Wouldn't you be able to cut off the fudged up arm and weld on a the old one? Other wise, yep RTT, http://www.polycount.com/forum/showthread.php?t=58411

I would simplify it a bit,
Original model, UV1, the material looks good on the model but the UV's are a mess.
Final model, UV1, the material looks like a mess on the model, but the UV's are good.
Select the final model, fire up RTT, enable projection and target the original model, bake out your maps.

Since you're using projection you can also transfer the normal map. When you transfer maps without using projection and only use 1 mesh, you have to rebake the normal map from whatever high poly source mesh because surface bump/normal maps are not included unless you use projection.

You do NOT want to put your normal map in the diffuse slot and bake that way, it will seriously screw up your normal map because its dependent on each pieces orientation.
Example: If you had a piece that needed to be rotated 90 degrees if you transferred the normal map without using projection, that new piece would have its normals facing the wrong way and it would cause seams and all kinds of weird shading.

Long post short: If you're going to transfer normal maps, either rebake from the source mesh or use projection.

Xenobond

You really only need 1 model for the RTT, no projection needed.
Copy the original UVs to channel 2.
Make the final, good set of UVs on channel 1.
Make sure the texture in the material is using channel 2.
Then when rendering make sure that it's rendering down to channel 1.

Mark Dygert

Xenobond wrote: »

You really only need 1 model for the RTT, no projection needed.
Copy the original UVs to channel 2.
Make the final, good set of UVs on channel 1.
Make sure the texture in the material is using channel 2.
Then when rendering make sure that it's rendering down to channel 1.

Then you run into not being able to transfer the normal map if you don't use projection. If you're doing just diffuse and spec, no problem but if you've got a normal map you need to use projection, or rebake the normal map from the high poly source.

You can't stick a normal map in the diffuse slot and transfer it that way, especially if you've rotated the UV pieces. A normal map is dependent on the orientation of each UV piece.

For example if you rotated this indent 90 degrees clockwise, it wouldn't shade correctly, green would be in the wrong spot as well as blue and red.

BUT if you use projection it take the surface maps into account as just height data and correctly colorizes the new orientation of the UV pieces without having to bake the normal map from scratch. So this piece would be rotated but green would be in the right spot.

If you only use one model and no projection you will never be able to transfer the normal map unless you use projection.

cman2k

Nice points Vig....gotta remember that one.