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What am I looking at?

This is Conway's Game of Life, but built in a cube instead of on a flat sheet of graph paper.

Imagine a huge 3D grid — like a Rubik's cube with 60 blocks along each edge. Every little box in that grid is a cell, and each cell is either alive or empty. Nothing here is designed or animated by hand. The whole thing runs on one tiny rule that gets applied to every cell at the same time, over and over:

• If a cell is alive, it counts how many of its 26 touching neighbours are alive. If that number is on the survive list, it lives on. Otherwise it starts to fade out.
• If a box is empty, it counts its living neighbours too. If that number is on the birth list, a new cell appears there.

That's it. Repeat a few hundred times and the cube starts doing things nobody programmed: blobs that pulse and breathe, crystals that grow in straight lines, structures that crawl across the grid and rebuild themselves, and patterns that spread until they fill everything.

Reading the rule

The Rule box uses three parts, survive / birth / states. For example 4/4/5 means "stay alive with exactly 4 neighbours, be born with exactly 4 neighbours, and take 5 steps to disappear once you start dying." The states number is why dying cells linger as grey ghosts instead of vanishing — it gives the structures a visible history. Try the presets; small changes to these numbers produce wildly different worlds.

A couple of details worth knowing

• The grid wraps around. Something leaving the right face comes back in on the left, so there are no walls. The faint wireframe box shows where that boundary is.
• Gold cubes are alive. Grey cubes are fading out and no longer count as neighbours.
• Only the cubes you could actually see are sent to the graphics card, which is why a 60³ grid — 216,000 cells — stays smooth.

Where this came from

This started as a final project for CS175: Computer Graphics at Harvard, written in C++ with OpenGL. This page is that program rebuilt to run in a browser with WebGL2, with a faster simulation step, instanced rendering, and controls you can actually click.

Keyboard

v space	play / pause
m	advance one generation
o	reseed randomly
c	clear the grid
f	toggle flat shading
s	save a PNG screenshot
← →	previous / next rule preset
r	recenter the camera
h ?	open this panel
drag	orbit · scroll or right-drag to zoom

Source: github.com/maxballison/CS175Final