Civilization Speedrun

What this is

A whole civilization arc in 4 minutes. A Perlin-noise earth bakes into a painted map with elevation, coastlines, and rivers. Four tribes bloom from the corners as living watercolor stains. Capitals pulse. Settlements speckle like firelight. Tech unlocks tied to terrain. Alliances form. Wars break out with crossed-swords markers. The era HUD ticks Stone → Bronze → Iron → Industrial → Atomic. Either someone hits 55% domination, the last tribe stands, or the year-5000 timeout fires — then the world resets.

Why this is mind-blowing

Every seed tells a different history. Sometimes a corner is mostly water and that tribe is stuck with naval tech they can't use. Sometimes two tribes ally early and steamroll. Sometimes the Atomic Age arrives just as the timer hits zero and the map is a four-color stalemate. It's the entire shape of human civilization compressed into a watchable loop, and chat will pick favorites by tribe color from the first 30 seconds.

Build a single-file HTML page that runs an entire 5000-year civilization speedrun on a 120×80 procedural earth. Four tribes start in the corners. They expand, hit terrain, unlock techs, form alliances, declare war, conquer, and eventually one dominates 55% of the world or the timer runs out. Era HUD ticks Stone → Bronze → Iron → Industrial → Atomic. Auto-reset after the victory card. No user input — autoplay forever.

What I learned shipping it

FBM Perlin terrain baked into a cached canvas with a dirty-flagged territory layer is the only way to repaint a 9600-tile map at 17 ticks/sec without slideshow.

Per-tribe Set territory plus an incrementally-maintained border Set lets expansion run in O(border) per tick, not O(world).

Gating tech branches on owned terrain (forest/river/hills/desert/mountain) makes geography matter — coastal tribes naval-tech, mountain tribes mining-tech.