Physics Particles Debris

App: apps/physics_particles_debris/

Demonstrates the Tier 2 particle system: each particle is a Jolt dynamic body that collides with the world. Particles are emitted continuously from a point above the ground and bounce realistically. Active particle count is logged every second.

Run from root

% ./plume3d physics_particles_debris

What it does

• Loads Models/ParticlesDebris.blend (optional — falls back to a code-only scene if missing).
• Creates a ParticleEmitter via Scene.createParticleEmitter with a pool of 64 bodies.
• Calls emitter.play() immediately to start continuous emission at 15 particles/sec.
• Each particle has a lifetime of 3 seconds; expired particles are returned to the pool.
• Logs activeCount / maxBodies every second.
• Shadow mapping enabled.

Emitter creation

_emitter = _scene.createParticleEmitter(
    "DebrisEmitter",  // name
    64,               // maxBodies  — body pool size
    0.08,             // size       — particle radius (m)
    0.5,              // mass       — particle mass (kg)
    3.0,              // lifetime   — seconds before despawn
    15.0,             // emissionRate — particles per second
    0.0, 3.0, 0.0    // initial position (x, y, z)
)
_emitter.play()

Monitoring

// In update(dt):
Logger.info("Particles: %(_emitter.activeCount)/%(_emitter.maxBodies) active")

Blend setup (optional)

If Models/ParticlesDebris.blend is absent, the app creates a fallback code-only scene with a ground plane and a default point light. To use a blend:

Object	Class	Notes
Ground plane	in Environment collection	Static rigid body
Camera	GameCamera	Tag: main_camera
Light	GameLight	Tag: main_light

APIs

• ParticleEmitter — createParticleEmitter, play, stop, burst, activeCount, maxBodies, setPosition, setNormal.
• Scene — createParticleEmitter.
• Physics — collision layers govern particle-world interactions.
• Graphics — setLights, setShadowMappingEnabled.