Generated art and sound

Why there are no image files, and how to change what things look like.

6 min read

Nothing in a starter kit is a file. Every sprite is drawn onto a canvas when the game loads, and every sound is synthesised. A project is a few kilobytes of description rather than a folder of assets, which is why a new one opens instantly and an export is tiny.

Changing how something looks

Open Assets, pick a generated texture, and change its parameters. Most take a palette, a size and a seed.

  • palette — a named colour set: hero, neon, slime, goblin, canary, drone, cyan, red, violet, amber, orange, teal, grass, stone.
  • seed — any number. The same seed always produces the same art, so a project never changes appearance between reloads.

The generators

Generator Produces
character A walking character sheet with run, jump and fall frames
creature An enemy
spaceship A ship, top-down
vehicleTop A car, top-down
prop Crates, rocks, obstacles
pickup / gemSet Coins, gems, collectables
button A UI button — shape, style, fill/border colour and a text label
tileset A terrain tileset with slopes
raceTrack A circuit, plus the racing line the AI follows
maze A maze or a set of rooms, plus its grid
groundPlane A seamlessly tiling road or terrain, for Mode-7
gradientSky / starfield / cityscape Backdrops

Using your own art

Upload an image under Assets and reference it like any other texture. Uploads are type-checked by content rather than by file extension.

Sound

Sound effects are synthesised from a type and a few parameters — laser, explosion, pickup, jump, noise, engine, hit. Change the type or the duration and it is a different effect, with no file to re-record.