What the fire screensaver is
A hot row is seeded along the bottom of a small grid. Every cell above takes its neighbour’s heat minus a small random amount, with a sideways nudge that produces the curl. Scaling the little grid up to the display is what gives the soft edges.
It is a genuinely elegant piece of code — one of those cases where the naive approach happens to look exactly right. It has been reimplemented on almost every platform since 1993 for that reason.
- A background for a stream, a party or a stage screen
- A striking full-screen effect on a television
- A demonstration of the algorithm itself, running live
Full screen flames in a browser tab
The heat control changes how fast the fire decays as it rises. Turned up, the flames reach the top of the screen; turned down, they stay as a shallow band along the bottom.
There is no hearth or surround here — the flames are the whole picture, edge to edge.
How to run the fire screensaver full screen
Press the fullscreen button on the player, or the F key. Escape brings you back to the page. On a desktop browser F11 does the same job and hides the browser’s own toolbars as well, which is what you want on a display that is going to be left running.
Everything you change in the settings is written into the address bar as you change it, so the version you have set up is a link. Bookmark it, or send it to whoever is running the screen. Space pauses and resumes at any time.