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"""PySide2 port of the opengl/legacy/overpainting example from Qt v5.x"""

import sys
import math, random
from PySide2.QtCore import *
from PySide2.QtGui import *
from PySide2.QtWidgets import *
from PySide2.QtOpenGL import *

try:
    from OpenGL.GL import *
except ImportError:
    app = QApplication(sys.argv)
    messageBox = QMessageBox(QMessageBox.Critical, "OpenGL overpainting",
                             "PyOpenGL must be installed to run this example.",
                             QMessageBox.Close)
    messageBox.setDetailedText("Run:\npip install PyOpenGL PyOpenGL_accelerate")
    messageBox.exec_()
    sys.exit(1)


class Bubble:
    def __init__(self, position, radius, velocity):
        self.position = position
        self.vel = velocity
        self.radius = radius
        self.innerColor = self.randomColor()
        self.outerColor = self.randomColor()
        self.updateBrush()

    def updateBrush(self):
        gradient = QRadialGradient(QPointF(self.radius, self.radius), self.radius,
                                   QPointF(self.radius*0.5, self.radius*0.5))

        gradient.setColorAt(0, QColor(255, 255, 255, 255))
        gradient.setColorAt(0.25, self.innerColor)
        gradient.setColorAt(1, self.outerColor)
        self.brush = QBrush(gradient)

    def drawBubble(self, painter):
        painter.save()
        painter.translate(self.position.x() - self.radius,
                          self.position.y() - self.radius)
        painter.setBrush(self.brush)
        painter.drawEllipse(0, 0, int(2*self.radius), int(2*self.radius))
        painter.restore()

    def randomColor(self):
        red = random.randrange(205, 256)
        green = random.randrange(205, 256)
        blue = random.randrange(205, 256)
        alpha = random.randrange(91, 192)

        return QColor(red, green, blue, alpha)

    def move(self, bbox):
        self.position += self.vel
        leftOverflow = self.position.x() - self.radius - bbox.left()
        rightOverflow = self.position.x() + self.radius - bbox.right()
        topOverflow = self.position.y() - self.radius - bbox.top()
        bottomOverflow = self.position.y() + self.radius - bbox.bottom()

        if leftOverflow < 0.0:
            self.position.setX(self.position.x() - 2 * leftOverflow)
            self.vel.setX(-self.vel.x())
        elif rightOverflow > 0.0:
            self.position.setX(self.position.x() - 2 * rightOverflow)
            self.vel.setX(-self.vel.x())

        if topOverflow < 0.0:
            self.position.setY(self.position.y() - 2 * topOverflow)
            self.vel.setY(-self.vel.y())
        elif bottomOverflow > 0.0:
            self.position.setY(self.position.y() - 2 * bottomOverflow)
            self.vel.setY(-self.vel.y())

    def rect(self):
        return QRectF(self.position.x() - self.radius,
                      self.position.y() - self.radius,
                      2 * self.radius, 2 * self.radius)


class GLWidget(QGLWidget):
    def __init__(self, parent = None):
        QGLWidget.__init__(self, QGLFormat(QGL.SampleBuffers), parent)

        midnight = QTime(0, 0, 0)
        random.seed(midnight.secsTo(QTime.currentTime()))

        self.object = 0
        self.xRot = 0
        self.yRot = 0
        self.zRot = 0
        self.image = QImage()
        self.bubbles = []
        self.lastPos = QPoint()

        self.trolltechGreen = QColor.fromCmykF(0.40, 0.0, 1.0, 0.0)
        self.trolltechPurple = QColor.fromCmykF(0.39, 0.39, 0.0, 0.0)

        self.animationTimer = QTimer()
        self.animationTimer.setSingleShot(False)
        self.connect(self.animationTimer, SIGNAL("timeout()"), self.animate)
        self.animationTimer.start(25)

        self.setAttribute(Qt.WA_NoSystemBackground)
        self.setMinimumSize(200, 200)
        self.setWindowTitle(self.tr("Overpainting a Scene"))

    def freeResources(self):
        self.makeCurrent()
        glDeleteLists(self.object, 1)

    def setXRotation(self, angle):
        angle = self.normalizeAngle(angle)
        if angle != self.xRot:
            self.xRot = angle
            self.emit(SIGNAL("xRotationChanged(int)"), angle)

    def setYRotation(self, angle):
        angle = self.normalizeAngle(angle)
        if angle != self.yRot:
            self.yRot = angle
            self.emit(SIGNAL("yRotationChanged(int)"), angle)

    def setZRotation(self, angle):
        angle = self.normalizeAngle(angle)
        if angle != self.zRot:
            self.zRot = angle
            self.emit(SIGNAL("zRotationChanged(int)"), angle)

    def initializeGL(self):
        self.object = self.makeObject()

    def mousePressEvent(self, event):
        self.lastPos = QPoint(event.pos())

    def mouseMoveEvent(self, event):
        dx = event.x() - self.lastPos.x()
        dy = event.y() - self.lastPos.y()

        if event.buttons() & Qt.LeftButton:
            self.setXRotation(self.xRot + 8 * dy)
            self.setYRotation(self.yRot + 8 * dx)
        elif event.buttons() & Qt.RightButton:
            self.setXRotation(self.xRot + 8 * dy)
            self.setZRotation(self.zRot + 8 * dx)

        self.lastPos = QPoint(event.pos())

    def paintEvent(self, event):
        painter = QPainter()
        painter.begin(self)
        painter.setRenderHint(QPainter.Antialiasing)

        glPushAttrib(GL_ALL_ATTRIB_BITS)
        glMatrixMode(GL_PROJECTION)
        glPushMatrix()
        glMatrixMode(GL_MODELVIEW)
        glPushMatrix()

        self.qglClearColor(self.trolltechPurple.darker())
        glShadeModel(GL_SMOOTH)
        glEnable(GL_DEPTH_TEST)
        glEnable(GL_CULL_FACE)
        glEnable(GL_LIGHTING)
        glEnable(GL_LIGHT0)
        lightPosition = ( 0.5, 5.0, 7.0, 1.0 )
        glLightfv(GL_LIGHT0, GL_POSITION, lightPosition)

        self.resizeGL(self.width(), self.height())

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
        glLoadIdentity()
        glTranslated(0.0, 0.0, -10.0)
        glRotated(self.xRot / 16.0, 1.0, 0.0, 0.0)
        glRotated(self.yRot / 16.0, 0.0, 1.0, 0.0)
        glRotated(self.zRot / 16.0, 0.0, 0.0, 1.0)
        glCallList(self.object)

        glPopAttrib()
        glMatrixMode(GL_MODELVIEW)
        glPopMatrix()
        glMatrixMode(GL_PROJECTION)
        glPopMatrix()

        glDisable(GL_CULL_FACE) ### not required if begin() also does it

        for bubble in self.bubbles:
            if bubble.rect().intersects(QRectF(event.rect())):
                bubble.drawBubble(painter)

        painter.drawImage((self.width() - self.image.width())/2, 0, self.image)
        painter.end()

    def resizeGL(self, width, height):
        side = min(width, height)
        glViewport(int((width - side) / 2), int((height - side) / 2), side, side)

        glMatrixMode(GL_PROJECTION)
        glLoadIdentity()
        glOrtho(-0.5, +0.5, +0.5, -0.5, 4.0, 15.0)
        glMatrixMode(GL_MODELVIEW)

        self.formatInstructions(width, height)

    def showEvent(self, event):
        self.createBubbles(20 - len(self.bubbles))

    def sizeHint(self):
        return QSize(400, 400)

    def makeObject(self):
        list = glGenLists(1)
        glNewList(list, GL_COMPILE)

        glEnable(GL_NORMALIZE)
        glBegin(GL_QUADS)

        logoDiffuseColor = (self.trolltechGreen.red()/255.0,
                            self.trolltechGreen.green()/255.0,
                            self.trolltechGreen.blue()/255.0, 1.0)
        glMaterialfv(GL_FRONT, GL_DIFFUSE, logoDiffuseColor)

        x1 = +0.06
        y1 = -0.14
        x2 = +0.14
        y2 = -0.06
        x3 = +0.08
        y3 = +0.00
        x4 = +0.30
        y4 = +0.22

        self.quad(x1, y1, x2, y2, y2, x2, y1, x1)
        self.quad(x3, y3, x4, y4, y4, x4, y3, x3)

        self.extrude(x1, y1, x2, y2)
        self.extrude(x2, y2, y2, x2)
        self.extrude(y2, x2, y1, x1)
        self.extrude(y1, x1, x1, y1)
        self.extrude(x3, y3, x4, y4)
        self.extrude(x4, y4, y4, x4)
        self.extrude(y4, x4, y3, x3)

        NumSectors = 200

        for i in range(NumSectors):
            angle1 = (i * 2 * math.pi) / NumSectors
            x5 = 0.30 * math.sin(angle1)
            y5 = 0.30 * math.cos(angle1)
            x6 = 0.20 * math.sin(angle1)
            y6 = 0.20 * math.cos(angle1)

            angle2 = ((i + 1) * 2 * math.pi) / NumSectors
            x7 = 0.20 * math.sin(angle2)
            y7 = 0.20 * math.cos(angle2)
            x8 = 0.30 * math.sin(angle2)
            y8 = 0.30 * math.cos(angle2)

            self.quad(x5, y5, x6, y6, x7, y7, x8, y8)

            self.extrude(x6, y6, x7, y7)
            self.extrude(x8, y8, x5, y5)

        glEnd()

        glEndList()
        return list

    def quad(self, x1, y1, x2, y2, x3, y3, x4, y4):
        glNormal3d(0.0, 0.0, -1.0)
        glVertex3d(x1, y1, -0.05)
        glVertex3d(x2, y2, -0.05)
        glVertex3d(x3, y3, -0.05)
        glVertex3d(x4, y4, -0.05)

        glNormal3d(0.0, 0.0, 1.0)
        glVertex3d(x4, y4, +0.05)
        glVertex3d(x3, y3, +0.05)
        glVertex3d(x2, y2, +0.05)
        glVertex3d(x1, y1, +0.05)

    def extrude(self, x1, y1, x2, y2):
        self.qglColor(self.trolltechGreen.darker(250 + int(100 * x1)))

        glNormal3d((x1 + x2)/2.0, (y1 + y2)/2.0, 0.0)
        glVertex3d(x1, y1, +0.05)
        glVertex3d(x2, y2, +0.05)
        glVertex3d(x2, y2, -0.05)
        glVertex3d(x1, y1, -0.05)

    def normalizeAngle(self, angle):
        while angle < 0:
            angle += 360 * 16
        while angle > 360 * 16:
            angle -= 360 * 16
        return angle

    def createBubbles(self, number):
        for i in range(number):
            position = QPointF(self.width()*(0.1 + 0.8*random.random()),
                               self.height()*(0.1 + 0.8*random.random()))
            radius = min(self.width(), self.height())*(0.0125 + 0.0875*random.random())
            velocity = QPointF(self.width()*0.0125*(-0.5 + random.random()),
                               self.height()*0.0125*(-0.5 + random.random()))

            self.bubbles.append(Bubble(position, radius, velocity))

    def animate(self):
        for bubble in self.bubbles:
            self.update(bubble.rect().toRect())
            bubble.move(self.rect())
            self.update(bubble.rect().toRect())

    def formatInstructions(self, width, height):
        text = self.tr("Click and drag with the left mouse button "
                       "to rotate the Qt logo.")
        metrics = QFontMetrics(self.font())
        border = max(4, metrics.leading())

        rect = metrics.boundingRect(0, 0, width - 2*border, int(height*0.125),
                                    Qt.AlignCenter | Qt.TextWordWrap, text)
        self.image = QImage(width, rect.height() + 2*border,
                            QImage.Format_ARGB32_Premultiplied)
        self.image.fill(qRgba(0, 0, 0, 127))

        painter = QPainter()
        painter.begin(self.image)
        painter.setRenderHint(QPainter.TextAntialiasing)
        painter.setPen(Qt.white)
        painter.drawText((width - rect.width())/2, border,
                         rect.width(), rect.height(),
                         Qt.AlignCenter | Qt.TextWordWrap, text)
        painter.end()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    window = GLWidget()
    window.show()
    res = app.exec_()
    window.freeResources()
    sys.exit(res)
