// For illustration / debugging of what's being updated.
protected virtual void DrawUpdateRectangle(Graphics gr)
{
Pen pen = new Pen(Color.Gray);
Rectangle r = UpdateRectangle.Grow(-1);
gr.DrawRectangle(pen, r);
pen.Dispose();
}
protected void InternalUpdateScreen(int ix, int iy)
{
Rectangle r = canvas.Clip(UpdateRectangle.Grow(ix, iy));
if (canvas.OnScreen(r))
{
canvas.CopyToScreen(r);
}
}
public virtual void UpdateScreen(int ix = 0, int iy = 0)
{
Rectangle r = canvas.Clip(UpdateRectangle.Grow(ix, iy));
if (canvas.OnScreen(r))
{
canvas.CopyToScreen(r);
}
}
public bool OnScreen(int dx, int dy)
{
return(canvas.OnScreen(UpdateRectangle.Grow(dx, dy)));
}
public virtual bool IsSelectable(Point p)
{
return(UpdateRectangle.Contains(p));
}
