title: How to add point declared in array of numbers on graphics panel
body: <p>I am developping my graph digitalizing software and I would like to make it easy for user to delete any of the points. For this reason I use a quadruple array of the doubles which containts x of showed point, y of showed point, x value of this point and y value of this point. This is needed for removing any of the value points, because it makes an association between showed points and value points.
  But instad of adding new showed points on graphics, the showed point just moves to the new place.</p>
  <p>Graphics code:</p>
  <pre><code>            Graphics canvas = e.Graphics;
              Pen pn = new Pen(pointcolor);
              foreach (double[] pnt in valpoints)
              {
                  Point pnt1 = new Point(Convert.ToInt32(pnt[0]) - 2, Convert.ToInt32(pnt[1]));
                  Point pnt2 = new Point(Convert.ToInt32(pnt[0]) + 2, Convert.ToInt32(pnt[1]));
                  Point pnt3 = new Point(Convert.ToInt32(pnt[0]), Convert.ToInt32(pnt[1]) - 2);
                  Point pnt4 = new Point(Convert.ToInt32(pnt[0]), Convert.ToInt32(pnt[1]) + 2);
                  canvas.DrawLine(pn, pnt1, pnt2);
                  canvas.DrawLine(pn, pnt3, pnt4);
              }
  </code></pre>
  <p>Point collection (into list of arrays) code:</p>
  <pre><code>                    valpoint[0] = e.X;
                      valpoint[1] = e.Y;
                      valpoint[2] = graphX;
                      valpoint[3] = graphY;
                      dataGridView1.Rows.Add(graphX.ToString(), graphY.ToString());
                      valpoints.Add(valpoint);
                      siskinsoftPanel2.Refresh();
  </code></pre>
  <p>Does anybody know, how to solve this problem? If you don't understand this question, pleas ask me.</p>