Magnetic Particles (Pygame Zero)

A small educational physics simulation built with Pygame Zero.

Particles interact using a simple inverse-square force model, move across the screen, and bounce off the window boundaries.

Preview

What You Can Learn

• How to structure a basic real-time simulation loop (draw + update) in Pygame Zero.
• How pairwise forces are computed between particles.
• How velocity and position are updated each frame.
• How boundary collisions can be handled with simple reflection.
• How simulation constants affect visual behavior.

How It Works

Each particle has:

• Position: x, y
• Velocity: vx, vy
• Accumulated force: forceX, forceY
• Radius, mass, and charge

At every frame:

1. Forces are computed for each particle pair.
2. The force is converted to acceleration (F / m) and applied to velocity.
3. Velocity updates position.
4. Particles are clamped to the window bounds and bounce.

Project Structure

• main.py: Full simulation logic and Pygame Zero entry point.
• requirements.txt: Python dependency list.
• magnetic_particles.gif: Visual preview used in this README.

Requirements

• Python 3.9+
• pgzero

Setup

1. Create and activate a virtual environment (recommended).
2. Install dependencies:

pip install -r requirements.txt

Run

python main.py

Tuning The Simulation

You can edit constants in main.py to experiment:

• COUNT: number of particles
• MINRADIUS, MAXRADIUS: particle size range
• MAXFORCE: cap on force magnitude for stability
• WIDTH, HEIGHT: simulation window size
• BG: background color

Try changing one value at a time and observe the emergent behavior.

Notes

• This is an educational model, not a physically accurate magnetic simulation.
• All particles are assigned positive charge in the current implementation.
• A force cap is used to prevent unstable motion when particles are very close.

License

This project is licensed under the terms in the LICENSE file.