Справка Houdini на русском Particles in Dynamics

Applying forces

You can direct particle motion with forces. Forces can emanate from geometry in the scene (for example, you can create a sphere and have it attract or repel particles), or you can create a general directional force (such as gravity).

How to direct particle motion with forces

To...Do this

Make geometry attract or repel particles

  1. Click the Point Attract or Curve Attract button from the Particles tab of the shelf.

  2. Select the particle system you want to be attracted or repelled and press Enter to confirm your selection.

  3. Select the object or curve you want the particles to be attracted to or repelled from and press Enter to confirm your selection.

The degree of attraction/repulsion can be modified with the Force Scale parameter on the Force tab of the POP Attractor node. A positive value will attract the particles and a negative value will repel the particles.

Create a general directional force

  1. Click the Force Particles tool on the Particles tab of the shelf.

  2. Select the particle system you want to be affected and press Enter to confirm your selection.

  3. Set the Force parameter on the POP Force node to affect the particles. By default this is set to -9.81 in the Y direction, to apply a gravity force.

Note

You can also use the Fan Particles or Wind on Particles tools on the shelf, depending on how you want the particles to react to the directional force.

Add random force to particles

  1. Click the Force Particles tool on the Particles tab of the shelf.

  2. Select the particle system you want to be affected and press Enter to confirm your selection.

  3. Modify the parameters on the Noise tab of the POP Force node. You can change the Swirl Size, Pulse Length, Roughness, Turbulence, etc,

Move particles along, toward, or around a curve

  1. Create a curve using the Draw Curve shelf tool.

  2. Create a particle system along the curve using the Location or Source shelf tools.

  3. Click the Curve Force tool on the Particles tab.

  4. Select the curve you want to affect your particles and press Enter.

Make particles flock together

  1. Create a particle system along the curve using the Location or Source shelf tools.

  2. Click the Flock tool on the Particles tab.

    You can choose the Number of Centers on the POP Flock node to determine how many different clusters of particles are formed. You can also the modify the parameters on the Interaction Force tab to control how much they stay together and how far apart they can get.

Tip

To create more realistic simulations, do not continuously birth particles. You can also add some noise with a POP Force node for a more natural look.

Note

To move the flocks, you can use a POP Attract node to have them follow an object (such as a character), or use other POP Forces to direct them.

Particles in Dynamics

Getting started

Behavior

Next Steps

Reference