func NewStoneFieldGenerator(db *engine.EntityDB, fill float64) *StoneFieldGenerator {
grass := db.New()
db.Set(grass, "art", base.NewArt('.', 0, 1, 0, 0, 0, 0))
stone := db.New()
db.Set(stone, "art", base.NewArt('#', .7, .7, .7, 0, 0, 0))
return &StoneFieldGenerator{stone: stone, grass: grass, fill: fill}
}
