intersection method
Computes the intersection of this and other.
The intersection of two axis-aligned rectangles, if any, is always another axis-aligned rectangle.
Returns the intersection of this and other, or null if they don't
intersect.
Implementation
Rectangle intersection(Rectangle other) {
var x0 = max(left, other.left);
var x1 = min(left + width, other.left + other.width);
if (x0 <= x1) {
var y0 = max(top, other.top);
var y1 = min(top + height, other.top + other.height);
if (y0 <= y1) {
return new Rectangle(x0, y0, x1 - x0, y1 - y0);
}
}
return null;
}