def mousePressEvent(self, event):
'''
On mouse button down, create a new (infinitesmal) SegmentString and PointerTrackGhost.
freehandTool remembers and updates SegmentString.
'''
pointerEvent = PointerEvent()
pointerEvent.makeFromEvent(mapper=self, event=event)
'''
freehandCurve as QGraphicsItem positioned at event in scene.
It keeps its internal data in its local CS
'''
freehandCurve = SegmentString()
self.scene().addItem(freehandCurve)
freehandCurve.setPos(pointerEvent.scenePos)
'''
headGhost at (0,0) in scene
it keeps its local data in CS equivalent to scene
'''
headGhost = PointerTrackGhost()
self.scene().addItem(headGhost)
self.freehandTool.setSegmentString(segmentString=freehandCurve,
pathHeadGhost=headGhost,
scenePosition=pointerEvent.scenePos)
self.freehandTool.pointerPressEvent(pointerEvent)
def mouseReleaseEvent(self, event):
pointerEvent = PointerEvent()
pointerEvent.makeFromEvent(mapper=self, event=event)
self.freehandTool.pointerReleaseEvent(pointerEvent)
def mouseMoveEvent(self, event):
''' Tell freehandTool to update its SegmentString. '''
pointerEvent = PointerEvent()
pointerEvent.makeFromEvent(mapper=self, event=event)
self.freehandTool.pointerMoveEvent(pointerEvent)
