Maya 2013 vertex colors to Houdini 14 not working?

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I'm feeding a mesh from Maya that has vertex colors. The hda takes that mesh and does things and stuff based off the vertex colors (or default white if there are no colors).

No matter what I throw at the asset in Maya, however, it acts as if there are no vertex colors.

I've dug through the forums and found a few posts that lead me to believe that Maya color set to Houdini support was added back in Houdini 13. Since I found multiple posts saying this should be so, I'm very confused that I cannot get it to work with Houdini 14.
Is anyone else having trouble with this in 14? I'm using Maya 2013 if that makes any difference.

Is there a specific setup you have to do to get inputs to read vert colors?

Hope someone can help. I've included the hda and a maya file with a colored sphere for easy testing.

Attachments:
destroy_me.hda (22.4 KB)
color_sphere.mb (172.0 KB)

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Ah, I think you just missed one small detail. The “Cd” attribute goes in as a vertex attribute. Your asset is assuming the “Cd” to be a point attribute. It seems to work as soon as I change the haspointattrib() to hasvertexattrib() on the Color_Check node.

See the attached asset.

Attachments:
destroy_me2.hda (22.4 KB)

Andrew / アンドリュー
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Awsome awong, that worked perfectly. Thanks very much!

One new issue, the interior pieces all have no alpha in their vertex colors. See attached example.

Any ideas why this might be? Happens whether I clear the vertex colors in Houdini or not.

Attachments:
invis.JPG (152.0 KB)

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Hm, interesting. The Maya colorset is RGBA, which includes alpha. So the Maya plug-in transfers this into the “Alpha” attribute. And this “Alpha” attribute defaults to 0. This is different from the usual “Alpha” attribute in Houdini, which defaults to 1. This means that when the geometry is fractured, “Alpha” is set for the inside pieces, and they are set to 0.

One of these two ways would fix this:
1. Change the Maya colorset to just RGB.
2. Delete the Alpha attribute from inside your asset.
Andrew / アンドリュー
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Yup, adding an Alpha point attribute that defaults to 1 at the end of my tree worked great. Thanks very much!
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