The Attribute node is used for generic extraction of named attribute data from vertex maps, regardless of the source — Cinema 4D, Real Flow, Houdini, and the X-Particles Trail Object, for example. Use the output to drive suitable aspects of any material as needed. The Attribute node can extract Float or Color data. 


Helpful Information

As über-Octaner Raphael Rau (aka Silverwing) cites in his Octane Material Gotcha's video here, use of the Attribute node with Vertex Maps is also a great way to encapsulate vertex maps in a material via referencing, allowing for sharing of materials across scenes, in LiveDB and so on.


X-Particles

Create an X-Particles scene. Set up the xpTrail modifier, and choose the xpEmitter, per the X-Particles documentation. Once the scene is working to expectations, set up the Octane material for the xpTrail modifier:


    1. Add an Octane Object tag to the xpTrail object.
    2. Create the desired Octane material type, and assign it to the xpTrails object.
    3. Open the material in the Octane Node Editor.
    4. Add the Attribute node.
    5. Connect the node to the Diffuse input pin.


Play the scene. Stop the playback and activate the Live Viewer. The color scheme will be applied to the xpTrails object as seen in the Live Viewer window.