ludic/docs/language/random/random-chance.md

id	name	category	kind	tokens	sig	tip	order	ns	member
random-chance	Random.chance	random	namespace-method	Random.chance	Random.chance(percent) -> bool	Return true with the given percent probability.	1	Random	chance

Returns true roughly percent times out of a hundred, and false otherwise — a convenient shorthand for "this happens X% of the time". Use it to gate random events such as spawning an enemy on a given frame, dropping loot, or triggering a rare animation. Passing 0 never fires and 100 always fires. Like the rest of the Random namespace it is driven by the seeded generator, so seed it with Random.seed for reproducible behavior.

Parameters:

• percent — the probability of returning true, from 0 to 100

program SpawnWave {
  property Position { column: int = 0, row: int = 0 }
  model Enemy { Position }

  const GRID_WIDTH: int = 20
  const TILE_SIZE: int = 16

  handler SeedRandom phase Start {
    Random.seed(value: 3)
  }

  handler MaybeSpawn phase Update {
    if Random.chance(percent: 10) {
      spawn Enemy {
        Position { column: Random.range(low: 0, high: GRID_WIDTH - 1), row: 0 }
      }
    }
  }

  handler DrawWorld phase Render {
    Screen.clear(Color.MidnightBlue)
    for (Position) in query [Position, {Enemy}] {
      Screen.fill_rectangle(
        x: Position.column * TILE_SIZE,
        y: Position.row * TILE_SIZE,
        width: TILE_SIZE,
        height: TILE_SIZE,
        color: Color.Crimson)
    }
    Screen.show()
  }
}