Houdini 20.0 Shelf tools

Source from Volumes shelf tool

Continuously generates smoke, fire, or liquid from the interior of an object.

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This tool continuously generates fluid from the interior of an object and is similar to Source from Points and Source from Surface. Since sourcing is done from inside of the object, the selected geometry is required to be closed and watertight.


If selection consists of volume or VDB primitives, this shelf tool will instead import these into the DOP network. For example, you can manually create a divergence volume and import it into the simulation with this tool.

The tool will create a setup tailored towards the simulation it is applied to. In case of a smoke simulation, it will import density and temperature, causing smoke to rise from the selected object. If applied to a pyro simulation, the shelf tool will inject fuel and temperature, turning the surface into a flame source. Finally, the tool will add the necessary nodes to continuously emit liquid into a FLIP simulation, similar to Emit Particle Fluid.


If you want the sourced smoke to inherit the object’s motion, you can use the Point Velocity SOP to calculate its velocity. The velocity attribute will then be transferred to the scattered points by the Pyro Source node and converted into a VDB by the Volume Rasterize Attributes SOP.

Using Source from Volume

  1. Create an open geometry object within a container.

    For more information on containers see: Smoke Container or Pyro Container.

  2. Select the geometry object to generate the source.

  3. Click the Source from Volume tool on the Populate Containers tab.

  4. Select the container to put the source into and press Enter to confirm your selection.


To turn off the continuous flow of fluid, set the Activation to 0 on the Volume Source node in your DOP network. You can keyframe this parameter to control when the fluid is emitted.


If the object is only partially in the container, only the portion of the object that is within the container’s boundaries will be simulated.

See also

Shelf tools

Using the shelf

  • Customize the shelf

    How to change the look of the shelf, change and rearrange its contents, and create your own shelf tools.