"Rest" Node in 17.5?

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HI there, I'm working on a shot where a chunk of geometry is UV unwrapped based on the camera perspective. The texture works fine until the geometry moves and then it swims because it is aligned with the camera view.

Now I have used the rest node some in the past and it worse fines to hold the texture on a frame but I have only been able to use with the UV Cords node. I am using a custom material with a bind for an AOV and I need to use the rest, is that possible? I haven't been able to find any tutorials or help docs explaining how to make this work, o I thought I would turn to you guys for expert help.

The screenshots below have the examples of what my setups are using.

I really appreciate all ideas and help you can give!

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Screen Shot 2019-10-07 at 11.35.23 AM.png (235.7 KB)
Screen Shot 2019-10-07 at 11.35.43 AM.png (45.1 KB)

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The rest attribute is just a vector point attribute… if you Bind rest in your material via the Bind VOP, you can connect it as the lookup position for any other VOP that supports a vector for the input position.
MOPs (Motion Operators for Houdini): http://www.motionoperators.com [www.motionoperators.com]
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Thanks @toadstorm,

I'm not quite sure what you mean by the “lookup position”, in my first image example, where would I plug it in? I have the rest binded already in the image below.

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Screen Shot 2019-10-07 at 11.35.23 AM.png (273.8 KB)

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What property of this material are you trying to use the “rnml” attribute to drive? If it's the apparent normals of the material, you could plug the result into “baseN” and/or “coatN” depending on what you're trying to do here.
MOPs (Motion Operators for Houdini): http://www.motionoperators.com [www.motionoperators.com]
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@toadstorm,

I am trying drive the Base Texture UV property.

I looked for an “baseN” but I didn't see any on my material.

Here a simple file with just the material I am using so you can check sit the nodes im using. Let me know what I am missing.

Thanks.

Attachments:
Rest_Material_Example.hipnc (1.5 MB)

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Okay, I'm attaching a file that shows how you might approach this in two different ways.

You can do this in the material by binding the “rest” attribute and then using this to drive a Texture VOP or any kind of noise or whatever you want, and then using that result to drive a specific channel of your shader… in this case, diffuse color.

For your use case, though, it might be easier to just do the UV projection in a “rest” pose and then simply copy those UVs to the final mesh. If your topology doesn't change over time this will be much simpler and not require you to modify any materials at all.

Let me know if this isn't clear from the example!

Attachments:
rest_in_material.hip (522.2 KB)

MOPs (Motion Operators for Houdini): http://www.motionoperators.com [www.motionoperators.com]
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Ok, the issue is fixed now!

I ended up using the static-geo-uv-transfer method, and that worked out fine.

Thanks so much for the help, I will be sharing the final shot within the next 2 weeks on my website and LinkedIn , hope you get to see it.
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Edited by CreativeWaves - Oct. 8, 2019 11:19:47

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