Houdini 17.0 Shelf tools

Auto-Sleep Particles shelf tool

Allows grains to wake up and go to sleep based on the velocity of nearby particles.

On this page

This tool allows grains to wake up and go to sleep based on the motion of the simulation around it. It is similar to the Awake By Geometry shelf tool, but instead of activating particles strictly by being near an object, this tool setups up the simulation so that particles can be awakened by the velocity of the particles around them. Typically you would want to use this tool whenever you want to optimize your simulation, especially if only a small part of the simulation will be active at any given time. This is especially true if you've already used Awake By Geometry.

This tool adds a POP Awaken node with the Awaken by Nearby Particles checkbox turned on, and turns on the Enable Auto Sleep checkbox on the Sleeping tab of the POP Solver.

Using Auto-Sleep Particles

  1. Select the grain object you want to auto sleep.

  2. Click the Auto-Sleep Particles tool on the Grains tab.

For specific parameter information, see the POP Solver and POP Awaken help pages.

The green areas show particles that are awake, and the red areas show particles that are sleeping.

Tips

  • The Velocity Threshold parameter on the POP Awaken node will control how easily other particles are awaked by other fast moving particles.

  • The Wakeup Scale parameter on the POP Awaken node will control how large the wake up radius is around the particles being tagged by the Velocity Threshold.

  • Turn on the Start Asleep checkbox on the Sleeping tab of the POP Solver to ensure all the particles in your simulation start out sleeping. This is useful if you don’t want to let your sand settle. However, this can cause a drooping effect when sand is activated and settles.

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.

Shelf tabs

  • Create tab

    Tools on the Create tab let you create and place primitives, curves, and null objects in the scene view.

  • Modify tab

    Tools on the Modify tab let you easily customize objects in the scene view.

  • Model tab

    Tools on the Model tab let you edit objects in the scene view.

  • Polygon tab

    Tools on the Polygon tab let you modify polygons in the scene view.

  • Deform tab

    Tools on the Deform tab let you deform objects in the scene view.

  • Texture tab

    Tools on the Texture tab let you texture objects in the scene view.

  • Rigging tab

    The Rigging tab contains tools for creating premade rigs.

  • Muscles tab

    The Muscles tab contains tools for creating muscles.

  • Characters tab

    Tools on the Character tab let you create characters in the scene view.

  • Constraints tab

    Tools on the Constraints tab create a constraint network where you can constrain objects to each other in the scene view.

  • Hair Utils tab

    Tools on the Hair Utils tab let you quickly set up hair and fur on objects.

  • Guide Process tab

    Tools on the Guide Process tab let you influence the placement and orientation of guide hairs by painting skin attributes.

  • Guide Brushes tab

    Tools on the Grooming tab let you add and directly manipulate hair.

  • Terrain FX shelf tab

  • Cloud FX tab

    The Cloud FX tab contains tools for creating cloud effects.

  • Volume tab

    The Volume tab contains tools for creating volume effects.

  • Lights and Cameras tab

    Tools on the Lights and Cameras tab let you create and place lights and cameras in the scene view.

  • Collisions tab

    Tools on the Collisions tab let you create collision objects in the scene view.

  • Particles tab

    Tools on the Particles tab let you create dynamic particle simulations.

  • Grains tab

    The Grains tab contains tools for simulate grains of sand and other granular matter.

  • Vellum tab

    The Vellum tab contains tools for creating different types of vellum effects.

  • Rigid Bodies tab

    Tools on the Rigid Bodies tab let you create dynamic RBD objects in the scene view.

  • Particle Fluids tab

    Tools on the Particle Fluids tab let you create particle based liquids in the scene view.

  • Viscous Fluids tab

    Viscous fluids are FLIP simulations that use a temperature attribute to drive viscosity.

  • Oceans tab

    The Oceans tab contains tools for creating ocean simulations.

  • Fluid Containers tab

    The Fluid Containers tab contains tools for creating pyro, smoke, and liquid containers.

  • Populate Containers tab

    The Populate Containers tab contains tools for creating and removing fire, smoke, and liquid.

  • Container Tools tab

    The Container Tools tab contains tools for manipulating fire, smoke, and liquid.

  • Pyro FX tab

    Tools on the Pryo FX tab let you create simulated smoke and fire effects.

  • Solid tab

    Tools on the Solid tab let you create and modify solid objects.

  • Wires tab

    Tools on the Wires tab let you create flexible dynamic objects in the scene view.

  • Crowds tab

    The Crowds tab contains tools for creating crowds, crowd behaviors, as well as examples.

  • Drive Simulation tab

    Tools on the Drive Simulation tab let you manipulate dynamic objects in the scene view.

Technical