Sops to cops

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Coming from this one https://www.sidefx.com/forum/topic/51410/ [www.sidefx.com] so I don't hijack my own thread.

I got lucky because I could get the world position from the uvs. In the case of an arbitrary mesh I'd make a grid if points in world space that represent the pixels, do the tricks in sops and then bring the colors to cops.

Attachments:
sopcops.hipnc (202.5 KB)
ezgif-4-3fdd96eccf.gif (2.3 MB)

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excellent example!!!!
thank you for this

best regards
Patar
Edited by patar - 2017年8月27日 05:01:05
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Thanks! You're welcome
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Thanks for taking the time to do that example. I hope you agree that there are some Houdini improvements that would make this ‘type’ of effect easier.

#1 - COP Wrangle node with OCIO VEX functions
#2 - SOP Import Grid Points node (to ensure a 2d plane of points)
Houdini Indie
Karma/Redshift 3D
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OCIO Vex funtions, I'm sure that'd be cool, although for this specific example I don't imagine how they could be helpful, it might be because I haven't had the time or need to get around all the OCIO business.

#2. I'm not sure how that node would work. Look at the cop globals, we need a logic to import data. The most useful are the X and Y positions, analogous to u and v or s and t. So we need to find a correlation between that and world ( object ) space. So what I've done a couple of times before is transform the mesh to uv space and sample attributes from that geometry ( forget the pixel grid I talked about, I got confused with a related experiment ). Of course it needs to have properly laid out uvs.

I'm sorry I couldn't agree more, I'm just trying to be sincere AND constructive at the same time.

Toodles!!!
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The copnet sop does create a mesh with color from the image.
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jsmack
The copnet sop does create a mesh with color from the image.
I'm sure you misinterpreted. If not, maybe a hip file ?
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Hey, this example works great if the grid only has 1 primitive because you're specifying prim 0 in cops. I can't wrap my head around how to make this work for a more complex geometry with multiple primitives. Any idea?
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Colby Winfield
Hey, this example works great if the grid only has 1 primitive because you're specifying prim 0 in cops. I can't wrap my head around how to make this work for a more complex geometry with multiple primitives. Any idea?
I just noticed your post … Check updated scene.

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sopcops_v02.hipnc (265.9 KB)

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thanks for sharing!i am looking for something similar but much simpler.
i just have a circle resampled with point color and i want to bring that into cops for processing.

The Geometry node just brings the projected circle white without any color information which is a bummer
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