def ellipse_path(center, a, b, rotation=0):
if not isinstance(center, QPointF):
center = QPointF(*center)
brect = QRectF(-a, -b, 2 * a, 2 * b)
path = QPainterPath()
path.addEllipse(brect)
if rotation != 0:
transform = QTransform().rotate(rotation)
path = transform.map(path)
path.translate(center)
return path
def ellipse_path(center, a, b, rotation=0):
if not isinstance(center, QPointF):
center = QPointF(*center)
brect = QRectF(-a, -b, 2 * a, 2 * b)
path = QPainterPath()
path.addEllipse(brect)
if rotation != 0:
transform = QTransform().rotate(rotation)
path = transform.map(path)
path.translate(center)
return path
def paint (self, painter, style, widget=None):
assert isinstance(painter, QPainter)
if self.isSelected():
brush = QBrush(Qt.green)
else:
brush = QBrush(Qt.white)
pen = QPen(Qt.black)
circle_path = QPainterPath()
circle_path.addEllipse(self.boundingRect())
painter.fillPath(circle_path, brush)
painter.strokePath(circle_path, pen)
text_path = QPainterPath()
text_path.addText(0, 0, QFont(), str(self.node))
box = text_path.boundingRect()
text_path.translate(-box.center())
painter.fillPath(text_path, QBrush(Qt.black))
def overlay_for(pt1, pt2, frequency):
# Construct the line-geometry, we'll use this to construct the ellipsoid
line = QLineF(pt1, pt2)
# Determine the radius for the ellipsoid
radius = fresnel_radius(line.length(), frequency)
# Draw the ellipsoid
zone = QPainterPath()
zone.addEllipse(QPointF(0., 0.), line.length() / 2, radius)
# Rotate the ellipsoid - same angle as the line
transform = QTransform()
transform.rotate(-line.angle())
zone = transform.map(zone)
# Center the zone over the line
lc = QRectF(pt1, pt2).center()
zc = zone.boundingRect().center()
zone.translate(lc.x() - zc.x(), lc.y() - zc.y())
return line, zone
