pAvoid Node

pAvoid applies an anticipated repulsive force to particles approaching the region: the closer a particle gets to the region, the stronger the avoidance vector. The result: trajectories that naturally steer around the obstacle.

Unlike a negative pPoint Force (omnidirectional radial repulsion), pAvoid computes the escape vector relative to the specific region - directional steering out of the area.

• Effects Library: Tools > Particles > pAvoid
• Quick add: right-click in the Node Editor → Add Tool > Particles > pAvoid

pAvoid

Anticipates the obstacle and steers around it. Natural trajectory, no visible collision.

pBounce

Post-collision reaction. The particle hits the surface, then bounces. Visible impact.

Rule: a crowd steering around an obstacle → pAvoid. Rain hitting the ground and bouncing → pBounce.

• Particle Input (orange) - incoming stream.
• Region Input (green/magenta) - area to avoid (bitmap/mesh).

Crowd avoiding an obstacle:
pEmitter → pAvoid ← Shape 3D (obstacle cube)
                   (Distance 0.5, Strength 1.0)
         → pRender
(particles naturally steer around the cube)

Water flow avoiding a rock:
pEmitter (river) → pAvoid ← Shape 3D (rock sphere)
                  → pTurbulence → pRender

Insects avoiding a person:
pEmitter → pAvoid ← character mesh
         → pTurbulence (natural chaos) → pRender

Distance

Distance at which the particle starts avoiding the region. Larger = earlier anticipation (elegant steering). Smaller = late reaction (tight steering).

Strength

Intensity of the avoidance force. Positive = repulsion (avoidance). Negative = attraction (particles are drawn toward the area - rarely used).

Randomize

Seed for individual variations (keeps all particles from steering around in exactly the same way).

Conditions (Sets)

Avoidance only for certain sets.

• Flow around obstacles - particles representing water, air or a crowd that naturally steer around objects in the scene.
• A crowd avoiding a character - insects, dust or flying debris avoiding a filmed subject (believable collision).
• Natural steering vs hard collision - an aesthetic alternative to pBounce for the many scenarios where you want steering rather than bouncing.
• Magic protection field - an energy bubble pushing away the surrounding particles (shield, aura).
• A corridor to channel particles - 2 pAvoid nodes placed in parallel = particles pass between them without entering the avoidance areas.

• Distance > Strength = soft steering. Low Distance + high Strength = abrupt last-second avoidance.
• Limit: fast particles can get through - if speed + momentum exceed the avoidance force, particles pass through. Raise Strength or Distance to compensate.
• Combine with pBounce as a fallback - pAvoid as the main steering + pBounce with the same region as a backup = particles that steer around and bounce if they fail.
• Randomize ON for a natural look - without it, every particle steers around on the same side. Random varies the side.
• For AI crowd behaviors (humans avoiding each other), combine pAvoid + pFollow + pFlock.