# GPU Particles 2D

A GPU-driven particle fountain with gravity and colour fade.

```{raw} html
<a class="example-run-button" href="../demos/features_2d_gpu_particles.html">▶ Run in browser</a>

```

**Tags:** `2d` `particles` `gpu` `effects`

## What it demonstrates
  - GPUParticles2D: particle state lives on the GPU, simulated by a compute shader
  - Emission tuning: amount, lifetime, speed, speed_variance, spread, direction
  - gravity pulling particles back down to form a fountain arc
  - start_colour / end_colour fade over each particle's lifetime
  - Toggling emitting on/off and switching emission_shape at runtime

In 2D the Y axis points down, so direction (0, -1, 0) emits upward and a
positive-Y gravity (0, 200, 0) pulls particles back down: a classic fountain.

## Source

```{literalinclude} ../../examples/features/2d/gpu_particles.py
:language: python
:linenos:
```