Houdini 16.5 Shelf tools

Whitewater shelf tool

Creates spray, foam, and churn based on an underlying FLIP fluid simulation.

On this page

This tool sets up the source and solver for a whitewater simulation. Whitewater emission particles are created from a source FLIP or liquid simulation based on several criteria including fluid acceleration, curvature, and vorticity. The simulation uses these emission particles and volumes from the fluid simulations as sources for simulating whitewater with foam, spray and bubble particles.

Tip

Do not try to set up a whitewater simulation from scratch.

Using Whitewater

  1. Click the Whitewater tool on the Particle Fluids tab.

  2. Select a FLIP Fluid Object or Liquid Object and press Enter to complete your selection.

Note

You may need to navigate into the DOP Network containing the fluid object to select it.

Understanding the network of nodes

Whitewater Source

This is where the spray and foam come from, and where the most important parameters to change the look of your whitewater are located.

  • The Curvature tab on the Whitewater Source node allows you to control where the whitecap is created. You can specify at what surface curvature to emit whitewater as well as the Max Velocity Angle.

  • The Acceleration tab on the Whitewater Source node controls whitewater where then are velocity changes. For example, if the fluid changes direction suddenly, like when a wave collides with a rock and goes back in the opposite direction.

  • The Vorticity tab on the Whitewater Source node looks for areas that are spinning, or the curling of velocity. When water is churned, bubbles are created. This is not typically something you would want in an ocean, unless a boat is traveling through, or a person is failing around in the water.

Whitewater Sim

This where the whitewater simulated, and where you can modify the animation.

  • The Whitewater Emitter picks up points and uses them as sources to generate particles.

  • The Whitewater Solver is where you can control the three aspects of whitewater: foam, spray, and bubbles.

    • Foam are particles that sit on the surface. Advection Strength is an important parameter on this tab because it controls how strongly the foam sticks to the surface. Parameters on the Lifespan tab are also important because the let you control how long before the foam dissipates. For example, dense foam should live longer than if it was spread out thinly (less foam around).

    • Spray is particles that have left the surface. This tab is important to control how the spray will act. For example, adding Drag will prevent the spray from shooting too far away.

    • Bubbles are particles below the surface. This tab lets you control how closely the particles mimic the fluid around it, as well as how fast the bubbles move to the surface and turn into foam. Typically you use this in fast moving water simulations, such as a river.

Tip

Typically you will not need to make changes on the Solver tab.

Import Whitewater

This is the result of whitewater_source and whitewater_sim combined.

For information, on how to use particle fluid distribution with whitewater or how to animate a wave tank with whitewater, see whitewater.

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.

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.

  • 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.

  • Cloth tab

    Tools on the Cloth tab let you create and constrain cloth objects in the scene view.

  • 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