/// <summary>
/// Override InteractivePlotSurface2D.Refresh to update entire plotSurface
/// </summary>
public override void Refresh()
{
// Update the off-screen drawing cache, then QueueDrawArea raises
// an ExposeEvent to copy the cache to the screen, and this Event
// is raised immediately by calling ProcessUpdates().
UpdateCache();
canvas.QueueDrawArea(0, 0, canvas.Allocation.Width, canvas.Allocation.Height);
if (canvas.IsRealized)
{
Gdk.Window win = canvas.GdkWindow;
win.ProcessUpdates(true); // needs this for responsive updates as mouse moves
}
}