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nickdigital
11-02-2010, 03:16 PM
How does one get a UV Pass out of Lightwave?

I'm trying to play with this AfterEffects plug-in.
http://aescripts.com/yy_uvmapper/

Here’s how to do it in Softimage:
Get a texture_Projection_Lookup node and connect it to the material's surface input. Provided you have uv's on the surface it will render them.

So I guess the question is how do you translate the UV info to color info.

Lamont
11-03-2010, 05:41 AM
I saw a TextureUV Buffer on the Extended RPF Export. Never tried it.

Lightwolf
11-03-2010, 08:35 AM
UVMap Node -> (X,Y) db&w Channel Blender (Vector) -> Surface Color
Set Luminance to 100% and everything else to 0%.

A global option would be using shaderMeister, if you excuse the plug.

Cheers,
Mike

nickdigital
11-03-2010, 10:11 AM
Thanks for the info, I'll have to try that out.

monovich
11-03-2010, 03:04 PM
I use this technique all the time. Its great for reanimating animated texture maps in After Effects (like animated signs) without having to re-render the whole 3d part over and over.

I use the re:map plugin from trapcode. The AE Scripts one (or are there two?) is new.
Attached is a node and a screen grab.

you have to render this pass out with the right camera or it will be blocky and messed up because of reconstruction filters.
try the perspective camera with the classic reconstruction filter and the classic sampling pattern. I think that is the right setting. FPrime works as well @ render quality 3.

Render out to a 16 bit or better format. 8 bit doesn't have enough info for smooth remapping.

In After Effects I think you need to be in 16 bit or better colorspace for smooth remapping.

monovich
11-03-2010, 03:05 PM
p.s. I forget who makes that first UV map node. Might be DB&W or Dpont.

nickdigital
11-03-2010, 03:17 PM
Great info. Thanks for sharing.

Dodgy
11-03-2010, 10:03 PM
Alternatively, just slap the same UV node into a Math>Vector>multiply node with value <1,1,0> and pump that into the colour input and that'll convert the U/V to red/green.

You can use Dpont's Pixel filter and extra buffer nodes to save you rendering the scene again, just save it out to an image file when the scene renders.

nickdigital
11-03-2010, 10:39 PM
Good info Dodgy. Thx.

So much to learn, not only with nodes but DPont's stuff too...my head is gonna explode.

pyo
11-04-2010, 03:28 AM
It's not necessary to use DPont's nodes. All we need are standard LW nodes. See attached screenshot to check simplest (imho) setup for UV pass.

edit: well, the simplest way for uv pass is to plug DPont's UV node directly into diffuse. The problem is that this node output values in -0.5 to 0.5 range. If your compositing program can handle UV pass like that than this is the simplest way. If it's needed to be in 0.0 - 1.0 range then use the setup from attached image or use DPont's UV node, plug it to vector add node with 0.5,0.5,0.0 values and then plug directly to diffuse input.

Cageman
07-06-2012, 01:31 AM
We are testing this technique with Nuke.... I have a box, atlasmapped (very simple stuff), but one of the sides has negative values which seems to cause issues in Nuke...

Any ideas on how to remap this value?

Jim M
07-06-2012, 03:26 AM
Remap node?

Cageman
07-06-2012, 05:39 AM
Remap node?

Tried that after I had found the remap node from DB&W, but it still doesn't seem to work correctly.

Jim M
07-06-2012, 05:48 AM
Strange. I can't see why it wouldn't.
Could also try a manual remap with a couple of gradient nodes after the UV outputs?

Sensei
07-06-2012, 08:53 AM
UVMap Node -> (X,Y) db&w Channel Blender (Vector) -> Surface Color
Set Luminance to 100% and everything else to 0%.


I would take UV Node then connect to Tools > Make Vector, then to Diffuse Shading. So, no need to adjust Luminance (and lights are not calculated- so it's faster).

Sensei
07-06-2012, 08:56 AM
We are testing this technique with Nuke.... I have a box, atlasmapped (very simple stuff), but one of the sides has negative values which seems to cause issues in Nuke...


You have UV < 0.0?? What for..

Math > Scalar > Abs (Absolute) will convert negative to positive value. Prior Tools > Make Vector.

Cageman
07-13-2012, 12:09 AM
Sorry that I didn't get back to this thread sooner.... we get the UV-pass out correctly now! :)

However, we are having lots of problems with aliasing, so in most cases, changing textures in post is a no go. Anyone else being able to deal with aliasing issues?

Sensei
07-13-2012, 12:15 AM
Textures in renderer are passed through mip-mapping. I bet compositing software is not doing it.

Double/triple resolution render and rescaling is not helping?

Cageman
07-13-2012, 12:35 AM
Nopes.

Lightwolf
07-13-2012, 03:02 AM
Textures in renderer are passed through mip-mapping. I bet compositing software is not doing it.
Actually, at least Fusion is if the right routines are used. However, that would also require more information than just the uv coordinates.

Cheers,
Mike

ernpchan
10-03-2014, 06:33 PM
You can use Dpont's Pixel filter and extra buffer nodes to save you rendering the scene again, just save it out to an image file when the scene renders.

Sorry to resurrect an old thread, but can someone point out the steps to get the UV pass as a separate rendered channel?

Sensei
10-03-2014, 06:45 PM
Maps > UV Map, make Vector, and plug to Diffuse Shading.

gerardstrada
10-04-2014, 04:45 PM
How does one get a UV Pass out of Lightwave?

I'm trying to play with this AfterEffects plug-in.
http://aescripts.com/yy_uvmapper/

Here’s how to do it in Softimage:
Get a texture_Projection_Lookup node and connect it to the material's surface input. Provided you have uv's on the surface it will render them.

So I guess the question is how do you translate the UV info to color info.
You might want to take a look at this:

http://lightwiki.com/wiki/Multipass_Rendering_with_Filter_Node_Editors#UV_Te xture_Pass



Gerardo

ernpchan
10-29-2014, 01:24 PM
So I'm rendering out a box with the UVs piped into Diffuse Shading but when I apply a texture via reVision's reMap the image is squashed on one side. The demo content that comes with the plugin works just fine. So is this a LW UV render problem?

Sensei
10-29-2014, 01:41 PM
Color space? :)

ernpchan
10-29-2014, 01:41 PM
Color space? :)

Yes! I just figured that out now. Had to set my footage to Preserve RGB in AE.

Sensei
10-29-2014, 02:35 PM
Remember that you can use TrueArt's Node Library > Tools > Color Convert node, so you can make nodal trees with and without color-space conversion on demand (f.e. triggered by null, frame etc).