# Particles

<a href="/demos/3d_particles.html">Play Demo</a>

Particle Effects Demo — Showcases sub-emitters, collision, trails, GPU particles, and deterministic seeding.

Demonstrates:
  - Firework: upward burst, sub_emitter_death creates sparkle explosion
  - Waterfall: particles fall and bounce off ground plane
  - Comet: moving emitter with trail rendering
  - Deterministic toggle: press R to restart with same seed, proving identical replay

Run: uv run python packages/graphics/examples/3d_particles.py

Controls:
    1       - Firework burst
    2       - Toggle waterfall
    3       - Toggle comet
    R       - Restart all (deterministic replay)
    A / D   - Orbit camera
    W / S   - Zoom in / out

## Source Code

```{literalinclude} ../../packages/graphics/examples/3d_particles.py
:language: python
:linenos:
```