Method grow

include/math.hpp:423–428

Expands each corner. */

	}
	/** Expands each corner. */
	Rect grow(Vec delta) const {
		Rect r;
		r.pos = pos.minus(delta);
		r.size = size.plus(delta.mult(2.f));
		return r;
	}
	/** Contracts each corner. */
	Rect shrink(Vec delta) const {
		Rect r;