Add custom properties on emission

You can add custom properties to aero as well as particle simulations, including granular MPM effects. These custom properties can be used for any purpose — for example, you can modulate them using influences and then use them to control shading properties.

1. Add a set_property node to the graph.

2. Set its key to the name that you want to call the property.

   • Note that for aero simulations, "voxel_" will be automatically prepended to the property name if it is not included. This is important to know because you must use the exact name of the property with vary_source_property and in other situations.
   • Once the property has been added, you can confirm its final name by putting a watchpoint on the object output of the simulation node. See Diagnose and debug graphs .

3. Set its value to the initial value that you want.

   • If you want a different type than float, connect a value node of the desired type. See Add a value node.
   • For aero simulations, the value is applied only where smoke is emitted. It gets transported with the smoke, and is zero everywhere else.

4. Connect the output of the set_property node to the additional_properties port of a source node.

You can connect have any number of set_property nodes connected into a source node.