I am trying to do my particle simulations inside of houdini 16 and render them using Cycles in Blender. I’ve exported a simple particle sim using the Ogawa encoding and imported it into Blender. I can see the particles as black dots in the viewport but not in the render, I guess they are just being imported as points? How can I render them and how can I use the color attributes, which are being exported by houdini?
I could probably just use the imported points to replace them with objects, but that would still mean, that I cannot use color information or any information at all except the position.
Cycles will import the points as a mesh (a sort of animated point cloud). You can use dupliverts to attach objects to them. Rotation always follows the vertex normal, you may need to transfer the @orient attribute in Houdini into @N before exporting the Alembic. Note that since this is a single pointing vector, rotation around the pointing vector (@up in Houdini) can’t be exported.
At least with a complete mesh (iirc, not with points) point colors from Houdini should be accessible as a vertex color layer called “Cd”. It might not show up in vertex paint or in the mesh panel, but you can call it from Cycles like any other vertex paint layer with the attribute node. I don’t think it transfers to duplivert objects though. Depending on what you’re doing with the particles, it’s often easier to clone meshes onto the particles in Houdini and send the finished mesh to Blender.