examples/airship/main.go
func (p *player) RotateLeft() {
	p.angle--
	if p.angle < 0 {
		p.angle += maxAngle
	}
	p.lean--
	if p.lean < -maxLean {
		p.lean = -maxLean
	}
}
func (p *player) RotateLeft() {
	p.angle--
	if p.angle < 0 {
		p.angle += maxAngle
	}
	p.lean--
	if p.lean < -maxLean {
		p.lean = -maxLean
	}
}
// RotateLeft rotates the player p in the left direction.