How to check intersection between 2 rotated rectangles?

Question

Can someone explain how to check if one rotated rectangle intersect other rectangle?

Answer 1

Here's the same algorithm in Java if anybody is interested.

boolean isPolygonsIntersecting(Polygon a, Polygon b)
{
    for (int x=0; x<2; x++)
    {
        Polygon polygon = (x==0) ? a : b;

        for (int i1=0; i1 maxA)
                    maxA = projected;
            }

            double minB = Double.POSITIVE_INFINITY;
            double maxB = Double.NEGATIVE_INFINITY;

            for (Point p : b.getPoints())
            {
                double projected = normal.x * p.x + normal.y * p.y;

                if (projected < minB)
                    minB = projected;
                if (projected > maxB)
                    maxB = projected;
            }

            if (maxA < minB || maxB < minA)
                return false;
        }
    }

    return true;
}