material ID
Particle shapes can have various material IDs so that user can assign various materials through the Multi/Sub-Object Material.
[Inputs]
#Particle Stream - This pin requires a particle stream to be connected. Connection is usually not required if any of the attributes is connected.
Enabled - Enable or disable node evaluation.
Material ID - Material ID that you want to assign to particle and/or shape.
Write to Shape - Each particle can carry the material ID value that you can share and use with other nodes. However, in order to render a particle shape with certain material the material ID must be written to the shape.