qtreearrow.h #1

// QTreeArrow: a custom QCanvasBezierCurve gizmo.  Implemented from
// scratch and provides no collision detection. 

class QTreeArrow : public QCanvasItem
{
public:
	QTreeArrow::QTreeArrow( QTreeRevBall* source, QTreeRevBall* target, 
		FLCArrowType type, Contrib contrib );
	virtual QTreeArrow::~QTreeArrow();

	// The following methods are all abstract QCanvasItem methods. 

	// Draw a bezier curve-shaped arrow from source to target. 
	void draw( QPainter& p );

	// The bounding rectangle is valid but very optimistic. 
	QRect boundingRect() const;

	// No real collision detection possible with this implementation. 
	virtual bool collidesWith( const QCanvasItem* other ) 
		const { return false; };
	virtual bool collidesWith
		( 
		const QCanvasSprite*,
		const QCanvasPolygonalItem*,
		const QCanvasRectangle*,
		const QCanvasEllipse*,
		const QCanvasText* 
		) const { return false; };

	// Update the pen based on available data.
	void UpdatePen();

private:
	QPoint start, end;
	QColor mycolor;
	QPen mypen;
	FLCArrowType atype;
	Contrib acontrib;
};