【PyQt4实例7】QPainter坐标系的变换【转载】

#-*- coding:utf-8 -*-

from PyQt4.QtCore import *
from PyQt4.QtGui import *

QTextCodec.setCodecForTr(QTextCodec.codecForName("utf-8"))

class PainArea(QWidget):
def __init__(self):
super(PainArea,self).__init__()
self.setPalette(QPalette(Qt.white))
self.setAutoFillBackground(True)
self.setMinimumSize(400,400)

self.scale = 1
self.angle = 0
self.translate =0
self.shear = 0
def setScale(self,x):
self.scale = x/5.0
self.update()

def setTranslate(self,x):
self.translate = x
self.update()

def setRotate(self,x):
self.angle = x
self.update()

def setShear(self,x):
self.shear = (x-10.0)/10.0
self.update()
def paintEvent(self,e):
p = QPainter(self)
p.translate(200,200)

path = QPainterPath()
path.addRect(-100,-50,200,100)
p.rotate(self.angle)
p.scale(self.scale,self.scale)
p.translate(self.translate,self.translate)
p.shear(self.shear,self.shear)
p.setPen(Qt.red)
p.drawLine(0,0,150,0)
p.drawLine(148,-2,150,0)
p.drawLine(148,2,150,0)
p.drawText(150,2,"X")
p.drawLine(0,0,0,150)
p.drawLine(-2,148,0,150)
p.drawLine(2,148,0,150)
p.drawText(2,150,"Y")
p.setPen(Qt.blue)
p.drawPath(path)

class MainWindow(QWidget):
def __init__(self):
super(MainWindow,self).__init__()
self.setWindowTitle(self.tr("QPainter坐标系的变换"))
self.area = PainArea()
self.createwindow()
def slotRotate(self,x):
self.area.setRotate(x)

def slotScale(self,x):
self.area.setScale(x)

def slotTranslate(self,x):
self.area.setTranslate(x)

def slotShear(self,x):
self.area.setShear(x)

def createwindow(self):
self.rotatetext = QLabel(self.tr("旋转"))
self.rotatetspinbox = QSpinBox(self)
self.rotatetspinbox.setRange(1,10)
self.rotatetspinbox.valueChanged.connect(self.slotRotate)

self.scaletext = QLabel(self.tr("缩放"))
self.scalespinbox = QSpinBox(self)
self.scalespinbox.setRange(1,10)
self.scalespinbox.valueChanged.connect(self.slotScale)

self.translatetext = QLabel(self.tr("平移"))
self.translatespinbox = QSpinBox(self)
self.translatespinbox.setRange(1,10)
self.translatespinbox.valueChanged.connect(self.slotTranslate)

self.sheartext = QLabel(self.tr("切变"))
self.shearspinbox = QSpinBox(self)
self.shearspinbox.setRange(1,10)
self.shearspinbox.valueChanged.connect(self.slotShear)

self.rightlayout = QVBoxLayout()
self.rightlayout.addWidget(self.rotatetext)
self.rightlayout.addWidget(self.rotatetspinbox)
self.rightlayout.addWidget(self.scaletext)
self.rightlayout.addWidget(self.scalespinbox)
self.rightlayout.addWidget(self.translatetext)
self.rightlayout.addWidget(self.translatespinbox)
self.rightlayout.addWidget(self.sheartext)
self.rightlayout.addWidget(self.shearspinbox)

self.leftlayout = QHBoxLayout()
self.leftlayout.addWidget(self.area)

self.mainlayout = QHBoxLayout()
self.mainlayout.addLayout(self.leftlayout)
self.mainlayout.addLayout(self.rightlayout)
self.setLayout(self.mainlayout)

if __name__ == '__main__':
import  sys
app = QApplication(sys.argv)
mainwindow = MainWindow()
mainwindow.show()
sys.exit(app.exec_())