def wheelEvent(self, event: QWheelEvent):
if event.modifiers() & Qt.ControlModifier \
and event.buttons() == Qt.NoButton:
# Zoom
delta = event.angleDelta().y()
# use mouse position as anchor while zooming
anchor = self.transformationAnchor()
self.setTransformationAnchor(QGraphicsView.AnchorUnderMouse)
self.__setZoomLevel(self.__zoomLevel + 10 * delta / 120)
self.setTransformationAnchor(anchor)
event.accept()
elif event.source() == Qt.MouseEventNotSynthesized \
and (event.angleDelta().x() == 0 \
and not self.verticalScrollBar().isVisible()) \
or (sys.platform == 'darwin' and event.modifiers() & Qt.ShiftModifier
or sys.platform != 'darwin' and event.modifiers() & Qt.AltModifier):
# Scroll horizontally
x, y = event.angleDelta().x(), event.angleDelta().y()
sign_value = x if x != 0 else y
sign = 1 if sign_value >= 0 else -1
new_angle_delta = QPoint(sign * max(abs(x), abs(y), sign_value), 0)
new_pixel_delta = QPoint(0, 0)
new_modifiers = event.modifiers() & ~(Qt.ShiftModifier
| Qt.AltModifier)
new_event = QWheelEvent(event.pos(), event.globalPos(),
new_pixel_delta, new_angle_delta,
event.buttons(), new_modifiers,
event.phase(), event.inverted(),
event.source())
event.accept()
super().wheelEvent(new_event)
else:
super().wheelEvent(event)
def wheelEvent(self, event: QWheelEvent):
# Zoom
if event.modifiers() & Qt.ControlModifier \
and event.buttons() == Qt.NoButton:
delta = event.angleDelta().y()
# use mouse position as anchor while zooming
anchor = self.transformationAnchor()
self.setTransformationAnchor(QGraphicsView.AnchorUnderMouse)
self.__setZoomLevel(self.__zoomLevel + 10 * delta / 120)
self.setTransformationAnchor(anchor)
event.accept()
# Scroll horizontally
elif self.__should_scroll_horizontally(event):
x, y = event.angleDelta().x(), event.angleDelta().y()
sign_value = x if x != 0 else y
sign = 1 if sign_value >= 0 else -1
new_angle_delta = QPoint(sign * max(abs(x), abs(y), sign_value), 0)
new_pixel_delta = QPoint(0, 0)
new_modifiers = event.modifiers() & ~(Qt.ShiftModifier
| Qt.AltModifier)
new_event = QWheelEvent(event.pos(), event.globalPos(),
new_pixel_delta, new_angle_delta,
event.buttons(), new_modifiers,
event.phase(), event.inverted(),
event.source())
event.accept()
super().wheelEvent(new_event)
else:
super().wheelEvent(event)
def wheelEvent(self, event: QWheelEvent):
if event.source() == Qt.MouseEventNotSynthesized and \
(event.modifiers() & Qt.ShiftModifier and sys.platform == 'darwin' or
event.modifiers() & Qt.AltModifier and sys.platform != 'darwin'):
new_event = QWheelEvent(event.pos(), event.globalPos(),
event.pixelDelta(), event.angleDelta(),
event.buttons(), Qt.NoModifier,
event.phase(), event.inverted(),
Qt.MouseEventSynthesizedByApplication)
event.accept()
super().wheelEvent(new_event)
else:
super().wheelEvent(event)
def wheelEvent(self, event: QWheelEvent):
# use mouse position as anchor while zooming
self.setTransformationAnchor(2)
if event.modifiers() & Qt.ControlModifier and event.buttons(
) == Qt.NoButton:
delta = event.angleDelta().y()
if (QT_VERSION >= 0x050500
and event.source() != Qt.MouseEventNotSynthesized
and abs(delta) < 50):
self.change_zoom(delta / 10)
else:
self.change_zoom(copysign(1, delta))
else:
super().wheelEvent(event)
def __should_scroll_horizontally(self, event: QWheelEvent):
if event.source() != Qt.MouseEventNotSynthesized:
return False
if (event.modifiers() & Qt.ShiftModifier and sys.platform == 'darwin'
or event.modifiers() & Qt.AltModifier
and sys.platform != 'darwin'):
return True
if event.angleDelta().x() == 0:
vBar = self.verticalScrollBar()
yDelta = event.angleDelta().y()
direction = yDelta >= 0
edgeVBarValue = vBar.minimum() if direction else vBar.maximum()
return vBar.value() == edgeVBarValue
return False
def wheelEvent(self, event: QWheelEvent):
# use mouse position as anchor while zooming
self.setTransformationAnchor(2)
if event.modifiers() & Qt.ControlModifier \
and event.buttons() == Qt.NoButton:
delta = event.angleDelta().y()
if QT_VERSION >= 0x050500 \
and event.source() != Qt.MouseEventNotSynthesized \
and abs(delta) < 50:
self.change_zoom(delta / 10)
else:
self.change_zoom(copysign(1, delta))
else:
super().wheelEvent(event)