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djwaterman
05-14-2013, 03:57 AM
I've been on a learning curve with UV mapping and generally always UV map everything if it needs a texture. But one thing I still don't know about. I'll try to describe it.

When dividing a surface into sections with separate UV maps and copying them into one big map, sometimes bits of geometry that share an edge in the map will get joined together along that edge. What is the procedure for keeping them separated?

I notice that this never happens with maps that use atlas. I can't find anything in LW's UV tools that will do this.

probiner
05-14-2013, 04:22 AM
LW discontinous points handling is not the best. A pair of UV seams are split info of a single edge. So when you copy a UV map chunk into a big unified map there's already info about those points in there, it's just they're respective to neighbor polygons.

So, to ensure you don't have this issue, use PLG "Unweld along UV" which unwelds the mesh on the UV seams and basically you get your mesh cut like the UV islands, having no discontinous points to deal with. Merge all, after you're done.

more about this issue in general, here: https://www.youtube.com/watch?v=Pwn0RuZwIwc

Cheers

sami
05-14-2013, 04:52 AM
I've been on a learning curve with UV mapping and generally always UV map everything if it needs a texture. But one thing I still don't know about. I'll try to describe it.

When dividing a surface into sections with separate UV maps and copying them into one big map, sometimes bits of geometry that share an edge in the map will get joined together along that edge. What is the procedure for keeping them separated?

I notice that this never happens with maps that use atlas. I can't find anything in LW's UV tools that will do this.

Probiner is right, but I'll actually suggest something different - forget UV mapping in LW entirely. Get 3DCoat, it is very LW friendly, you can pop models into and out of it and its UV mapping tools are amazing and easy to use. I know this doesn't exactly answer your question, but I never UV map anything at all in Lightwave any more except maybe a simple flat plane with planar UV mapping. Everything else is easily (and I mean hours and hours easier) done in 3DC on my LW objects and then pop them back into LW for further use. Seriously, 3DCoat's UV stuff is so nice, there is no point to attempt it in LW anymore (at least until a few versions from now when they finally add some nice features).

This video is for an old version of 3DC, and the new stuff for v4 is even nicer and faster. (this is also not mentioning the awesome painting, retopo, & sculpting that this app can do)


http://vimeo.com/7005596

djwaterman
05-14-2013, 05:53 AM
Probiner, how do you actually use that plugin? Do you have to actually select the seam first or does it automatically detect them on any given map? I haven't got it to work yet.

3Dcoat looks great, but I went with ZBrush and don't think I can justify buying another sculpting app, however I would never discount it.

Ryan Roye
05-14-2013, 06:19 AM
Probiner, how do you actually use that plugin? Do you have to actually select the seam first or does it automatically detect them on any given map?

Huh... I thought there was a decent UV tutorial out there, apparently I was wrong.

PLG tools can require a bit of tinkering with before the average user will understand what its doing and how to optimize work done with it, but UV mapping in Lightwave isn't really feasible without PLG tools (at least in version 9.6, mind you).

It'd take a video to explain meaningfully how to use PLG tools... I'm baffled that there aren't any out there aside from Erikals's videos (which focus on misc. aspects of the tools). It took me a long time of trial-and-error to figure it out on my own.

lardbros
05-14-2013, 07:38 AM
Newtek have been pretty poor at giving us any decent UV tools...

Doesn't anyone else ever have the issue where they unweld to UV stuff (which shouldn't be necessary... SURELY?) and then when you merge them back, it ruins your model because there are coincident points because you've been subpatch modelling, and you wanted a hard edge so smooth-shifted with no inset.

PLG tools are pretty amazing to be honest... they've fulfilled all my pelt mapping type needs. Until Newtek give us some nice discontinuous UV support, I'll continue to use PLG (fingers crossed they'll carry on working for the future).

probiner
05-14-2013, 08:33 AM
Probiner, how do you actually use that plugin? Do you have to actually select the seam first or does it automatically detect them on any given map? I haven't got it to work yet.

3Dcoat looks great, but I went with ZBrush and don't think I can justify buying another sculpting app, however I would never discount it.

Just have the intended map selected on the dropdown menu on the lower right corner.
Well the plugin works basically like copying and pasting the mesh per UV Island. If it doesn't work in isolation (meaning the pair is not present) just lasso the UV island and copy and paste. I refered the plugin because it's automatic.
But anyway, unweld ALL polygons should produce the same result without need to run the plugin. Just unweld all (no discontinous points) and just do the copy operations you were doing previously.

Cheers