qtest.py

import math, random, sys
from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *

class Window(QWidget):
    def __init__(self, imgQ, parent = None):
        QWidget.__init__(self, parent)
        self.thread = Worker()

        label = QLabel(self.tr("Number of stars:"))
        self.spinBox = QSpinBox()
        self.spinBox.setMaximum(10000)
        self.spinBox.setValue(100)
        self.startButton = QPushButton(self.tr("&Start"))
        self.viewer = QLabel()
        self.viewer.setFixedSize(300, 300)
        self.imgQ = imgQ

        # self.thread.finished.connect(self.updateUi)
        # self.thread.terminated.connect(self.updateUi)
        # self.thread.output['QRect', 'QImage'].connect(self.addImage)
        self.startButton.clicked.connect(self.makePicture)

        layout = QGridLayout()
        layout.addWidget(label, 0, 0)
        layout.addWidget(self.spinBox, 0, 1)
        layout.addWidget(self.startButton, 0, 2)
        layout.addWidget(self.viewer, 1, 0, 1, 3)
        self.setLayout(layout)
        self.setWindowTitle(self.tr("Simple Threading Example"))

    def makePicture(self):
        self.spinBox.setReadOnly(True)
        self.startButton.setEnabled(False)


        for i in range(self.imgQ.qsize()-1):
            self.imgQ.get()
        img = self.imgQ.get()

        height, width, channel = img.shape
        bytesPerLine = 3 * width
        qImg = QImage(img.data, width, height, bytesPerLine,
                            QImage.Format_RGB888)
        pixmap = QPixmap.fromImage(qImg)
        self.viewer.setPixmap(pixmap)
        # self.thread.render(self.viewer.size(), self.spinBox.value())

    def addImage(self, rect, image):
        pixmap = self.viewer.pixmap()
        painter = QPainter()
        painter.begin(pixmap)
        painter.drawImage(rect, image)
        painter.end()
        self.viewer.update(rect)

    def updateUi(self):
        self.spinBox.setReadOnly(False)
        self.startButton.setEnabled(True)

class Worker(QThread):
    output = pyqtSignal(QRect, QImage)
    def __init__(self, parent = None):
        QThread.__init__(self, parent)
        self.exiting = False
        self.size = QSize(0, 0)
        self.stars = 0

        self.path = QPainterPath()
        angle = 2 * math.pi / 5
        self.outerRadius = 20
        self.innerRadius = 8
        self.path.moveTo(self.outerRadius, 0)
        for step in range(1, 6):
            self.path.lineTo(
                self.innerRadius * math.cos((step - 0.5) * angle),
                self.innerRadius * math.sin((step - 0.5) * angle)
            )
            self.path.lineTo(
                self.outerRadius * math.cos(step * angle),
                self.outerRadius * math.sin(step * angle)
            )
        self.path.closeSubpath()

    def __del__(self):
        self.exiting = True
        self.wait()

    def render(self, size, stars):
        self.size = size
        self.stars = stars
        self.start()

    def run(self):
        # Note: This is never called directly. It is called by Qt once the
        # thread environment has been set up.
        random.seed()
        n = self.stars
        width = self.size.width()
        height = self.size.height()
        while not self.exiting and n > 0:
            image = QImage(self.outerRadius * 2, self.outerRadius * 2,
                           QImage.Format_ARGB32)
            image.fill(qRgba(0, 0, 0, 0))
            x = random.randrange(0, width)
            y = random.randrange(0, height)
            angle = random.randrange(0, 360)
            red = random.randrange(0, 256)
            green = random.randrange(0, 256)
            blue = random.randrange(0, 256)
            alpha = random.randrange(0, 256)

            painter = QPainter()
            painter.begin(image)
            painter.setRenderHint(QPainter.Antialiasing)
            painter.setPen(Qt.NoPen)
            painter.setBrush(QColor(red, green, blue, alpha))
            painter.translate(self.outerRadius, self.outerRadius)
            painter.rotate(angle)
            painter.drawPath(self.path)
            painter.end()

            self.output.emit(QRect(x - self.outerRadius, y - self.outerRadius,
                                   self.outerRadius * 2, self.outerRadius * 2),
                             image)
            n -= 1

if __name__ == "__main__":
    app = QApplication(sys.argv)
    window = Window()
    window.show()
    sys.exit(app.exec_())