Aruco markers with openCv, get the 3d corner coordinates?

Question

I am detecting a printed Aruco marker using opencv 3.2:

aruco::estimatePoseSingleMarkers(corners, markerLength, camMatrix, distCoeffs, rvecs,tvecs);
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Answer 1

Building upon @Quang's answer, C# code for transforming any point to camera coordinates. Of course it needs R and t vectors, so you're going to need a marker in order to get them.

private Point3d GetWorldPoint(Point3d input, Vec3d rvec, Vec3d tvec)
{
    var rot_mat = new Mat();

    Cv2.Rodrigues(MatOfDouble.FromArray(rvec.Item0, rvec.Item1, rvec.Item2), rot_mat);

    var pointProject = (rot_mat * MatOfDouble.FromArray(input.X, input.Y, input.Z)).ToMat();
    return tvec + new Point3d(pointProject.Get(0, 0), pointProject.Get(0, 1), pointProject.Get(0, 2));
}