class RubberBand : public LocalLoop
{
public:
	virtual void MouseMove(Point p, dword keyflags) 	{ AddPoint(p); GetMaster().Refresh(); }
	virtual void LeftUp(Point p, dword keyflags)    	{ EndLoop(); }
	virtual void RightUp(Point p, dword keyflags)   	{ EndLoop(); }

	const Vector<Point> &	GetPoints()					{ return points; }
	void 					Clear()						{ points.Clear(); }
private:
	Vector<Point> points;
	
	void AddPoint(const Point &newp);
};

void RubberBand::AddPoint(const Point &newp)
{
	if (points.GetCount() < 2)
		return points.Add(newp);
	// Get line vectors
	const Point &p = points[points.GetCount()-2];
	Point p1 = points.Top() - p;
	Point p2 = newp - p;
	// If gradient is different, add the new point
	if (p1.x*p2.y - p2.x*p1.y)
		points.Add(newp);
	// Otherwise update last points
	else
		points.Top() = newp;
}

	RubberBand 	band;
	BackDraw 	back;
	Size	 	backsz;
	
	void LeftDown(Point p, dword keyflags)
	{
		band.Clear();
		band.SetMaster(*this);
		Size sz = GetSize();
		if (sz != backsz) {
		    back.Create(sz);
		 	backsz = sz;   
		}
		Paint(back);
		band.Run();
		Refresh();
	}
	
	void Paint(Draw& w)
	{
		const Vector<Point> &p = band.GetPoints();
		if (!band.InLoop()) {
			// Normal painting
			w.DrawRect(GetSize(), White);	
			if (p.GetCount() >= 2) {
				w.DrawPolyline(p);	
				w.DrawLine(p[p.GetCount()-1], p[0]);
			}
						
		}
		else {
                        // RubberBand painting
			if (p.GetCount() >= 2)
				back.DrawLine(p[p.GetCount()-2], p.Top());
			back.Put(w, 0, 0);
			w.DrawText(4, 4, AsString(p.GetCount()));
		}
	}