public void DrawLine(Pen pen, Point pt1, Point pt2)
{
LibIGraph.DrawLine_Ints(this.native, pen.native, pt1.X, pt1.Y, pt2.X, pt2.Y);
}
public void DrawLine(Pen pen, int x1, int y1, int x2, int y2)
{
LibIGraph.DrawLine_Ints(this.native, pen.native, x1, y1, x2, y2);
}