JIGPX
JIGPX

POP Solver Example Setup

Basic particle system setup using POP Solver in Houdini

Overview

The POP (Particle Operator) Solver in Houdini is a powerful system for creating and manipulating particle simulations. This example demonstrates a basic setup for particle emission and behavior control.

Node Network Structure

Preview of a POP solver simulation in action

Preview of a POP solver simulation in action

Overview of the POP network structure showing the main components

Overview of the POP network structure showing the main components

Detailed view of the POP solver setup and particle controls

Detailed view of the POP solver setup and particle controls

Key Components:

  • POP Source: Controls particle emission, including birth rate and initial attributes
  • POP Force: Applies forces to the particles, such as gravity or wind
  • POP Drag: Adds air resistance to create more realistic particle movement
  • POP Group: Organizes particles into groups for targeted effects

Common Parameters

Essential Settings:

# POP Source Parameters
birthrate = 100
life = 2.5
impulse = 10
spread = 30

# POP Force Parameters
force = {0, -9.81, 0}  # Standard gravity
amplitude = 1.0

# POP Drag Parameters
drag = 0.1
turbulence = 0.05

Tips for Parameter Adjustment:

  • Increase birthrate for denser particle systems
  • Adjust life to control how long particles exist
  • Use spread to control the emission cone angle
  • Balance drag and turbulence for natural movement

Best Practices

  • Always use a null node at the network output for clean organization
  • Cache heavy simulations to disk using a File Cache SOP
  • Group particles early in the network for better control
  • Add visualization nodes (such as Trail SOP) for debugging
  • Use POP wrangler for custom particle behaviors