//Find innerPoint
            Point innerPoint;
            Point first = clipPolygon[0];
            Point second = clipPolygon[1];
            Point third = clipPolygon[2];
            if (clipPolygon.Length == 3)
            {
                innerPoint = new Point((first.x + second.x + third.x) / 3, (first.y + second.y + third.y) / 3);
            }
            else
            {
                innerPoint = new Point((first.x + third.x) / 2, (first.y + third.y) / 2);
            }