Another very common class template is Point. This class defines a 2D point specified by its coordinates x and y.
Like Point, there is a Point3 template class for 3D point support.
Like the Vec class, OpenCV defines the following Point aliases for our convenience:
typedef Point_<int> Point2i; typedef Point2i Point; typedef Point_<float> Point2f; typedef Point_<double> Point2d; The following operators are defined for points: pt1 = pt2 + pt3; pt1 = pt2 - pt3; pt1 = pt2 * a; pt1 = a * pt2; pt1 = pt2 / a; pt1 += pt2; pt1 -= pt2; pt1 *= a; pt1 /= a; double value = norm(pt); // L2 norm pt1 == pt2; pt1 != pt2;