c++ opencv中通过两个点的坐标计算角度

//计算两个点的角度

double CalculateAngle(Point Mar1Point, Point Mar2Point)

{

    double k = (double)(Mar2Point.y - Mar1Point.y) / (Mar2Point.x - Mar1Point.x);  //计算斜率

    double arcLength1 = atan(k);    //弧度

    double current_angle = arcLength1 * 180 / PI;  //角度

    return current_angle;

}