有人可以解释如何检查一个旋转的矩形是否与其他矩形相交？

请您参考如下方法:

1. 对于两个多边形中的每条边，检查它是否可以用作分隔线。如果是这样，你就完成了:没有交集。
2. 如果未找到分隔线，则存在交叉点。

/// Checks if the two polygons are intersecting. 
bool IsPolygonsIntersecting(Polygon a, Polygon b) 
{ 
    foreach (var polygon in new[] { a, b }) 
    { 
        for (int i1 = 0; i1 < polygon.Points.Count; i1++) 
        { 
            int i2 = (i1 + 1) % polygon.Points.Count; 
            var p1 = polygon.Points[i1]; 
            var p2 = polygon.Points[i2]; 
 
            var normal = new Point(p2.Y - p1.Y, p1.X - p2.X); 
 
            double? minA = null, maxA = null; 
            foreach (var p in a.Points) 
            { 
                var projected = normal.X * p.X + normal.Y * p.Y; 
                if (minA == null || projected < minA) 
                    minA = projected; 
                if (maxA == null || projected > maxA) 
                    maxA = projected; 
            } 
 
            double? minB = null, maxB = null; 
            foreach (var p in b.Points) 
            { 
                var projected = normal.X * p.X + normal.Y * p.Y; 
                if (minB == null || projected < minB) 
                    minB = projected; 
                if (maxB == null || projected > maxB) 
                    maxB = projected; 
            } 
 
            if (maxA < minB || maxB < minA) 
                return false; 
        } 
    } 
    return true; 
} 

有关更多信息，请参阅这篇文章:2D Polygon Collision Detection - Code Project

注意:该算法仅适用于按顺时针或逆时针顺序指定的凸多边形。