Springs [PICO8 1k Jam]

A simple graphical / physics demo for the PICO-1K Jam 2026 which models four connected springs that each have a mass on the end. Each spring is connected to the bottom of the one above. 

The top spring can be moved around using the cursor keys. If you wiggle it around you can see the cascading resonance or "whip" effect.

k = 0.3 -- this is the spring stiffness
d = 0.87 -- this is the damping
m = 5.0 -- this is the mass

x & y -- coords of the top spring

vx & vy -- velocity of the mass

rl -- is resting length of spring

The compressed byte size of the cartridge is 512. I've made very little effort to save bytes because the program is so simple in the first place.