def initialize(self, edge_id):
edge = graph.edge(edge_id)
if edge is not None:
self._id = edge_id
self._direction = edge.direction()
if self._begin is not None:
self._begin.positionChanged.disconnect(self.onItemMove)
if self._end is not None:
self._end.positionChanged.disconnect(self.onItemMove)
self._begin = self.scene().node(edge.head().id())
self._end = self.scene().node(edge.tail().id())
self._begin.positionChanged.connect(self.onItemMove)
self._end.positionChanged.connect(self.onItemMove)
self._calculate()
def _calculate(self):
p1 = self.mapFromItem(self._begin, 0, 0)
p2 = self.mapFromItem(self._end, 0, 0)
line = QLineF(p1, p2)
distance = line.length()
line = line.unitVector()
center = line.unitVector()
center.setLength(distance * 0.5)
center = center.p2()
line.setLength(self._begin.radius())
self._beginPoint = line.p2()
line = QLineF(p2, p1).unitVector()
line.setLength(self._end.radius())
self._endPoint = line.p2()
line = QLineF(self._endPoint, self._beginPoint)
self.setLine(line)
l = line.length()
self._path = QGraphicsLineItem.shape(self)
# self._path = QPainterPath() # QGraphicsLineItem.shape(self)
# self._path.moveTo(self._beginPoint)
# ln = line.unitVector()
# ln.setLength(l * 0.5)
# c = ln.p2()
# c.setX(c.x() + l * float(randint(-100, 100)) / 300.0)
# c.setY(c.y() + l * float(randint(-100, 100)) / 300.0)
# self._path.quadTo(c, self._endPoint)
# self._path.addEllipse(c, 5, 5)
if self._direction == EdgeDirection.STRAIGHT and l > 0.01:
angle = acos(line.dx() / l)
if line.dy() >= 0:
angle = pi * 2.0 - angle
p1 = line.p1() + QPointF(sin(angle + Edge._arrowAngle) * Edge._arrowSize,
cos(angle + Edge._arrowAngle) * Edge._arrowSize)
p2 = line.p1() + QPointF(sin(angle + pi - Edge._arrowAngle) * Edge._arrowSize,
cos(angle + pi - Edge._arrowAngle) * Edge._arrowSize)
arrow = QPolygonF()
arrow.append(p1)
arrow.append(line.p1())
arrow.append(p2)
self._path.addPolygon(arrow)
edge = graph.edge(self._id)
if edge is not None:
w = int(max(distance, 1))
edge.set_base_weight(w)
if self._text is None:
self._text = QGraphicsSimpleTextItem(str(w), self)
else:
self._text.setText(str(w))
self._text.setPos(center)
def onDirectionChange(self):
edge = graph.edge(self._id)
if edge is not None:
if self._direction != edge.direction():
self._direction = edge.direction()
self._calculate()
