Hello guys, i have a hair animation wich has color inside houdini, and i want to export the hair with the color tag on it in order to render it in c4d.

I can export the hair and put it into c4d, but it has no color, no color tag or anything wich i can use in octane to render it.

How can i solve it?

I have attached 2 screenshots for you to see.

Anyone?

How are you exporting the hair? Are you sure you're properly exporting the Cd attribute on the hair curves? Are you sure the attribute is making it to C4D?

freshbaked
How are you exporting the hair? Are you sure you're properly exporting the Cd attribute on the hair curves? Are you sure the attribute is making it to C4D?

-Im exporting it with the rop alembic output node.

-I have exported particles/meshes many times with the Cd attribute like this so yes i think im exporting it correctly.

-Well, im not sure because i cant see the color tag on C4D so i can colorize the hair with any color map.

Try promoting the Cd attrib to verticies before you export? I don't know what C4D wants, I've never used it before. Try asking on Maxon forums maybe?

freshbaked
Try promoting the Cd attrib to verticies before you export? I don't know what C4D wants, I've never used it before. Try asking on Maxon forums maybe?

Its already on point attribute, but nothing happens, theres no tag when i export it to c4d. If i export particles or meshes i can get any attribute/tag that i want, but with splines/hairs i cant.

Hope some admin can help

Yes I see that Cd is already on points, that's why I suggested promoting to vertices (they aren't the same thing in Houdini) and depending how C4D is interpreting the alembic data, it may make a difference.

freshbaked
Yes I see that Cd is already on points, that's why I suggested promoting to vertices (they aren't the same thing in Houdini) and depending how C4D is interpreting the alembic data, it may make a difference.

I have promoted Cd from point to vertices (vertex) and its the same, no tag on the spline or any color/attribute

attached the screenshots

Hi,
as far as I know, c4d does not load any curve attributes natively. You could try using Exprosso with Thinking Partices to capture the colours in the points of the curve and then reassemble the splines with the points or with the tracer - but that's just a thought.

Apart, have a look at the last post in this thread, it might help you.

Export Curves with Color to Cinema4d [www.sidefx.com]

Here the issue has been solved, but for Arnold (Houdini/Cinema4D). There the colour is read out as user data in the shader, maybe it is similar in Octane.

Read Cd attribute from Houdini splines in C4DtoA [forums.autodesk.com]

I know this is super late, but for anyone else stuck on this, it looks like c4d doesn't import the attributes for a curve/splines object. I have no idea why, but if the geometry doesn't have any thickness, it gets imported automatically as a spline, and without the color, or other attributes. I'm trying to trick the importer into thinking i'm importing normal geo, and then treat the objects as regular vertices with the attributes, but it keeps splitting the object to the spline part, and the solid parts.

It might have to do with the fact that cinema deals with no area/volume geometry in a weird way. Using the color attribute on geometry without width is looking quite impossible without some scripting or wizard c4d knowledge.

TLDR; Cinema probably treats zero-width geometry as splines only, and importing as splines with color is not directly supported afaik.