private void GLFrameTimer_Tick(object sender, EventArgs e)
 {
     try
     {
         GLSurface.Refresh();
     }
     catch (Exception ex)
     {
         MessageBox.Show(this, ex.ToString(), "Error: Can not handle Tick event.",
                         MessageBoxButtons.OK, MessageBoxIcon.Error);
     }
 }
 private void GLFrameTimer_Tick(object sender, EventArgs e)
 {
     GLSurface.Refresh();
 }