Python Pymunk Physics — ELI5

Imagine you build a marble run out of cardboard — tubes, ramps, funnels, and little bumpers. When you drop a marble at the top, it rolls down, bounces off bumpers, spins through the funnel, and lands at the bottom. You do not have to calculate where the marble goes; gravity and the bumpers do all the work.

Pymunk is like building that marble run inside your computer. You tell it, “Here is a ball. Here is a ramp. Here is gravity pulling everything down.” Then you press play, and Pymunk figures out all the bouncing, spinning, and sliding for you, one tiny time step at a time.

Every tick — maybe sixty times per second — Pymunk looks at every object, checks if anything is touching, calculates the push and pull, and moves everything a tiny bit. Repeat that fast enough, and it looks like real physics.

You can make objects heavy or light, bouncy or sticky, round or square. You can create springs that pull things together or motors that spin wheels. Everything follows the same rules you see in the real world, just simplified enough for a computer to handle quickly.

People use Pymunk for games (think Angry Birds-style catapults), science simulations (what happens when billiard balls collide?), and teaching (seeing physics rules come alive on screen is much more fun than reading equations in a textbook).

The one thing to remember: Pymunk is a virtual marble run — you set up shapes and rules, press play, and watch realistic 2D physics happen automatically.