untitled3000
Hello, 

I'm creating a flip sim in Houdini where the colors of the dynamic object mix. Similar to this:

 

I'd like to transfer the mixing point color of the simulation to maya and use it as an animated albedo texture in an Arnold shader. I've managed to import alembic files with color sets into maya, but only when the alembic file is a single frame. Unfortunately, I haven't had any luck importing multi framed alembic animations with changing topology while retaining point color information. I've done some research on the forums, and from what i gather you're supposed to use the arrayToPointColor node. So far that hasn't given me any results. 

Does anyone have a suggested workflow for something like this? Would I be better off converting the changing point color to a .png sequence in Houdini and then using the sequence as a texture map in maya?

Any help would be much appreciated. 

Thanks
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pshipkov
This should work well.
Switch the DG evaluation mode and see if this awakens the dependency graph.
I doubt this is the problem, but there is so much trouble seeping out of the PE these days that usually that's my first suggestion when somebody hits an data update/refresh problem.
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untitled3000
Still no luck. Maybe my setup is off? I've attached a screenshot of my node editor.

Screen Shot 2017-10-29 at 11.47.16 PM.png 

I've went ahead and created a aiUserDataColor node and referenced the color set name as the "color attr name". I then plugged in the aiUserDataColor node as color in my aiStandardShader. 

Could I be setting up the alembic file wrong? I'm just using default ROP alembic output settings. Should I be deleting and/or promoting any attributes? 

Thanks again!
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pshipkov
I think createColorSet has to be in front of arrayToPointColor.
If you provide me 2-3 frames of the alembic data i can take a look.
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untitled3000
Definitely! The alembic file is just an exported cache from the Houdini color mix example I posted above (incase you wanted to check out the project as well)  
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pshipkov
Everything i did:
createNode arrayToPointColor;
setAttr arrayToPointColor1.solidAlpha 1;
connectAttr flipColorMix_AlembicNode.outPolyMesh[0] arrayToPointColor1.inGeometry;
connectAttr flipColorMix_AlembicNode.prop[0] arrayToPointColor1.inRgbaPP;
connectAttr -f arrayToPointColor1.outGeometry particlefluidsurface1.inMesh;
setAttr particlefluidsurface1.displayColors 1;

and it worked just fine in both PE and DG evaluation modes.
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untitled3000
Awesome!!! That worked!

How would you go by linking that up to an Arnold Shader? From my understanding, you need to create a aiUserDataColor node and plug that into the color attribute of an Arnold Shader. I'm just not sure what to feed the aiUserDataColor node. 

Also, just to be on the same page, when the color is being applied in maya, are we applying the color to points or verts. I'm assuming the gradation in color wouldn't be as smooth on verts?

Thanks again! Very excited to add arrayToPointColor to my workflow! 
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pshipkov
Search the forums, i am pretty sure this was answered before.
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untitled3000
Sounds good. Found what I was looking for. Thanks again.
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