Copy UVs from ch1 to ch2 in 3ds Max?

wannabeartist · Jul 2011

Hi!

Is there an easy way of copying UVs from one channel to another for the same object?

I got some objects UV mapped but the maps are for ch1 - now I'd need ch2 for lightmapping and in this case the existing UVs would do fine. So now I just need an easy way to copy the UVs to ch2.

There's a bunch of these objects, so ideally it would work for several objects at once!

Octo · Jul 2011

You can probably make a script that does this with a click, but here's how i do it.
Go to Tools > Channel Info, hit Add...then copy and paste from 1:map to 2:map.

renderhjs · Jul 2011

you didn't specify a app so I am just assuming what fits me instead of you:
there is a existing maxscript tat does that called

copyUVWchannels

http://www.scriptspot.com/3ds-max/scripts/copyuvwchannels

There is also a build in channel dialogue in 3dsMax (from the very old 3dsMax days) that lists all of what max calls channels (vertex color, UV, geometry,..) and even their order is all wacky (0 or 1 index based- don't remember always odd in max anyways) so I don't even remember at which digit the UV channels started but with that tool you can copy the channels as well.

wannabeartist · Jul 2011

Thanks guys,

And renderhjs, what you mean? I'm talking about Max as indicated in the title

So that should work perfectly! Thanks for the link!

renderhjs · Jul 2011

ha my bad- missed that

Mark Dygert · Jul 2011

In max if you collapse the stack UV1 is baked into the mesh as the default UV layout for that object. Then if you apply UnwrapUVW again, change the channel to UV2 and click reset the layout for UV1 will appear in UV2.

You can also save UV1, switch to UV2 and load it.

Noors · Jul 2011

If you dont care about the stack, you can also apply the unwrap modifier on your object selection and change the map channel from 1 to to 2. If you don't "reset UWs", the uvs are just copied from channel 1 to 2. Then, just collapse, to "save" the uvs.

renderhjs script is certainly a cleaner way to do it though.

edit: ah FU vig

Mark Dygert · Jul 2011

I'm actually in the bushes outside your window, stealing your neighbors wifi, ninja posting whatever you're about to post. That furious clickiedy clack sound isn't a wood pecker... =P

leechdemon · Jul 2011

Totally ninja'ed.

My question though, is if your ok using the same UV's as on Channel 1, why do you want them on a second channel at all? Is this an engine requirement or something?

Noors · Jul 2011

Also, maybe he wants to pack several objects on the same map, and use the previous unwrap for it.

Mark Dygert · Jul 2011

Yea sometimes the channel has to be physically created in order for lightmaps to work in certain engines. With some engines if UV2 isn't there, it will create one and auto-unwrap the mesh making a mess instead of using UV1. Most engines have switches and settings to control this but often its easier to just make sure UV2 is set up to handle a lightmap properly.

leechdemon · Jul 2011

Gotcha. That makes sense, I suppose. It sounded like he was just using the exact same coords because "lightmaps need their own UV's". Cool.

Copy UVs from ch1 to ch2 in 3ds Max?

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