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Revanto
07-05-2018, 02:42 AM
Heya,

This is an old technique used in Maya.

https://www.youtube.com/watch?v=J7rWTPKMiT4

I was wondering if I could do something like this where you can deform a new mesh based on the UVs of another mesh or similar just like in the video.

I'm pretty sure I came across a way to do this in LW a long time ago but I can't find the video.

Any help?

Cheers,
Revanto :p

erikals
07-05-2018, 06:53 AM
hi, this UV morph example might spring some ideas on how to make it work >
https://forums.newtek.com/showthread.php?85719-Fun-with-Nodes-UV-morphing


https://youtu.be/crlUPD8BIwg


hm, looking again it might be a quite different technique

MonroePoteet
07-05-2018, 02:30 PM
It may not be what you're looking for, but you can deform a high-density mesh according to a low-density mesh using MetaLink. In the video you posted, it appears (although I could be wrong) that the objective is to have a hidden low-density mesh affected by deformers (like ClothFX) for performance, and those deformations are then reflected in a visible high-density mesh for rendering.

In LW isn't really by UV maps, though but by point locations in the low-density mesh. What I usually do is create the low-density mesh in Modeler, then copy it to another layer and subdivide it several times using Subdivide=>Metaform or Smoothed. It could be done the other way by creating / importing the high-density mesh and then using Reduce Polys to create the low-density mesh.

In Layout, you apply the desired dynamics to the low-density mesh (e.g. ClothFX), parent the high-density mesh to the low-density mesh, and apply FX_MetaLink to the high-density mesh.

Sorry if this isn't what you're after!! :)

mTp

jwiede
07-05-2018, 02:40 PM
In LW isn't really by UV maps, though but by point locations in the low-density mesh. What I usually do is create the low-density mesh in Modeler, then copy it to another layer and subdivide it several times using Subdivide=>Metaform or Smoothed. It could be done the other way by creating / importing the high-density mesh and then using Reduce Polys to create the low-density mesh.

The way you do it is generally the "better" way. The problem with doing it the other way is that the resultant points (and poly flow) in the low-density mesh won't always wind up yielding the exact same "structure" as that of the high-density mesh -- it very much depends on precisely what poly reduction method is used. Metalink tries to find equivalent bindings positionally, but depending on how much the low-density mesh's poly flow deviates from the high-density mesh, in some cases the difference in poly flow between low and high can result in some odd deformation artifacts.

If you're seeing artifacts in the deformation of the high-density meta-linked mesh, one of the things to check first is to ensure the low-density mesh's poly flow in the equivalent region roughly matches the poly flow of the high-density mesh. Seems obvious, but you'd be surprised how many get caught by that gotcha. That's why it's generally better to go from low->high (which ensures similar poly flow in both) than from high->low (which can change poly flow, depending on what reduction tool and settings are used). Of course, low->high isn't always an option, sometimes high->low must occur, in which case the user needs to ensure/verify poly flow similarity in the two (at least in deformation-important areas).

Revanto
07-05-2018, 08:04 PM
I have actually tried doing this on my friend's computer using 3d Sticker from 3rd Powers but I didn't get the result I wanted. Such a shame because I love watching the promo video of it and it looks really handy.

I honestly swear I saw a video of this being done with Lightwave and I can't find it on my system. Maybe I am remembering it wrong and it actually was in Maya but it was a variation that involved non-flattened geometry deformation...

Something like this might be achievable if you could set a bone at each point (in the flat UV state) and then morph those bones into the desired final mesh shape. That way you could add your own new mesh object and the result would be more accurate (hopefully!).

Well, I might have some experimenting to do then...

Thanks for everyone's feedback.

Revanto :p

erikals
07-06-2018, 07:22 AM
I honestly swear I saw a video of this being done with Lightwave

was it?  >


https://vimeo.com/13854535

MonroePoteet
07-06-2018, 10:50 AM
was it?  >


https://vimeo.com/13854535

Here's the webpage for the ConformByUV LScript (for LW9.6 it appears), which includes the pointer to the Vimeo tutorial

http://artstorm.net/plugins/conform-by-uv/

For some reason, the URL posted by erikals (THANKS!) doesn't show up in my Firefox browser.

mTp

Revanto
07-06-2018, 07:48 PM
No, it wasn't that video, erikals, but I will try this lscript anyway. BTW, I love your plugin experiment videos on youtube, erikals!

Don't worry about looking for that video I mentioned, guys. It would be like chasing the great white whale.

I'll try the plugin/lscipt and see if things work out. If it doesn't work out then no big deal. I just thought it would be a nice time-saving technique whereas you can work flat then deform that mesh to its intended 3d state. It would make retopology a bit quicker, too.

Much appreciated to you all!

Cheers,
Revanto :p

erikals
07-06-2018, 08:20 PM
no problem :)
maybe a solution will be found in the near future :)


BTW, I love your plugin experiment videos on youtube, erikals!

heyy, thanks, i appreciate that!   https://i.imgur.com/tJGL61i.png

Revanto
07-07-2018, 05:52 AM
OK, so I did try the Lscript but it didn't give me the result I wanted. While it did conform one mesh to another based on the UVs, it also worked like BG conform so there was point snapping that I didn't want. If you look at the video I first posted the UVs acted like a deformation mesh but there was no point snapping.

If you look at other videos on the Maya > Transfer Attributes tool, it'll give you a good idea of what I'd like to achieve. But like I mentioned before, if there is no solution then it's no big deal. I'm just naturally lazy so if I find a technique that saves me time then I'll jump on it like a starving velociraptor.

For example, many years ago I had to create multiple print sheets for 100+ game cards. Once I set up the right polygons, alphas and camera setup in Layout, I could use image sequences and render a few frames to give me the full print sheets I wanted easily and quickly. That was an awesome day when I found that trick out... :dance:

Rev. :p