Article Outline
Python pyqt (gui) example 'guidecircle'
Modules used in program:
import math
guidecircle
Python pyqt example: guidecircle
#############################################################################
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## Copyright (C) 2013 Riverbank Computing Limited.
## Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
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#############################################################################
import math
from PyQt5.QtCore import QPointF
from guide import Guide
PI2 = 2 * math.pi
class GuideCircle(Guide):
CW = 1
CCW = -1
def __init__(self, rect, startAngle=0.0, span=360.0, dir=CCW, follows=None):
super(GuideCircle, self).__init__(follows)
self.radiusX = rect.width() / 2.0
self.radiusY = rect.height() / 2.0
self.posX = rect.topLeft().x()
self.posY = rect.topLeft().y()
self.spanRad = span * PI2 / -360.0
if dir == GuideCircle.CCW:
self.startAngleRad = startAngle * PI2 / -360.0
self.endAngleRad = self.startAngleRad + self.spanRad
self.stepAngleRad = self.spanRad / self.length()
else:
self.startAngleRad = self.spanRad + (startAngle * PI2 / -360.0)
self.endAngleRad = startAngle * PI2 / -360.0
self.stepAngleRad = -self.spanRad / self.length()
def length(self):
return abs(self.radiusX * self.spanRad)
def startPos(self):
return QPointF((self.posX + self.radiusX + self.radiusX * math.cos(self.startAngleRad)) * self.scaleX,
(self.posY + self.radiusY + self.radiusY * math.sin(self.startAngleRad)) * self.scaleY)
def endPos(self):
return QPointF((self.posX + self.radiusX + self.radiusX * math.cos(self.endAngleRad)) * self.scaleX,
(self.posY + self.radiusY + self.radiusY * math.sin(self.endAngleRad)) * self.scaleY)
def guide(self, item, moveSpeed):
frame = item.guideFrame - self.startLength
end = QPointF((self.posX + self.radiusX + self.radiusX * math.cos(self.startAngleRad + (frame * self.stepAngleRad))) * self.scaleX,
(self.posY + self.radiusY + self.radiusY * math.sin(self.startAngleRad + (frame * self.stepAngleRad))) * self.scaleY)
self.move(item, end, moveSpeed)
Useful links
- Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
- Install PyQt: https://pythonbasics.org/install-pyqt/