Transfer a color attribute from houdini to c4d

[marcovalmori6]

Hi,

I've imported a particles simulation from houdini to c4d with 3 attributes: Cd, P and pscale; after that i set up an xpresso rig to read those attributes, and put an arnold tag and a standard shader to my alembic.

As far as the pscale everything works fine, but when i try to connect a user_data_rgb with "Cd" as my attribute, the color shown is the default one, it seems it cannot read that input.

The thing is, i can clearly see the different particles color in the viewport and in my thinking particles channel, i see the Cd(vector) listed.

Can anyone help me out? Thanks

[peter.horvath6V6K3 · Accepted solution]

I assume you are using the Arnold TP Group object to render Thinking Particles. It has a field, called Export channels, where you have to define which channels you want to export to Arnold. Did you define Cd there?

[marcovalmori6]

@Peter Horvath I was using an arnold tag on my alembic, but using a TP group solves the problem, thanks!

I do have another problem however, in the ipr the scale of the particles is correct, but when i render they all have the same size. I tried to add a pscale attribute in the tp group and put a user_data_float node in my shader network, but i'm not really sure where to connect it.

[peter.horvath6V6K3]

It's strange that it does not work in the render. Maybe it's an issue when the xpresso network is evaluated. Xpresso tag has a Priority option, you can try to change it if it helps. If it does not, can you send me your scene to take a look?

[marcovalmori6]

Changing the priority option to animation and then back to initial, solved the problem, thanks!