export type Vec = { x: number; y: number };

/** Build a vector from two numbers. */
export function vec(x: number, y: number): Vec {
	return { x, y };
}

/** a + b  (component-wise) */
export function add(a: Vec, b: Vec): Vec {
	return {
		x: a.x + b.x,
		y: a.y + b.y,
	};
}

/** a - b  (component-wise) */
export function sub(a: Vec, b: Vec): Vec {
	return {
		x: a.x - b.x,
		y: a.y - b.y,
	};
}

/** a scaled by the scalar s */
export function scale(a: Vec, s: number): Vec {
	return {
		x: a.x * s,
		y: a.y * s,
	};
}