lighting.py¶
import math
from PySide6 import QtCore, QtGui, QtWidgets
class Lighting(QtWidgets.QGraphicsView):
def __init__(self, parent=None):
super(Lighting, self).__init__(parent)
self.angle = 0.0
self.m_scene = QtWidgets.QGraphicsScene()
self.m_lightSource = None
self.m_items = []
self.setScene(self.m_scene)
self.setupScene()
timer = QtCore.QTimer(self)
timer.timeout.connect(self.animate)
timer.setInterval(30)
timer.start()
self.setRenderHint(QtGui.QPainter.Antialiasing)
self.setFrameStyle(QtWidgets.QFrame.NoFrame)
def setupScene(self):
self.m_scene.setSceneRect(-300, -200, 600, 460)
linearGrad = QtGui.QLinearGradient(QtCore.QPointF(-100, -100),
QtCore.QPointF(100, 100))
linearGrad.setColorAt(0, QtGui.QColor(255, 255, 255))
linearGrad.setColorAt(1, QtGui.QColor(192, 192, 255))
self.setBackgroundBrush(linearGrad)
radialGrad = QtGui.QRadialGradient(30, 30, 30)
radialGrad.setColorAt(0, QtCore.Qt.yellow)
radialGrad.setColorAt(0.2, QtCore.Qt.yellow)
radialGrad.setColorAt(1, QtCore.Qt.transparent)
pixmap = QtGui.QPixmap(60, 60)
pixmap.fill(QtCore.Qt.transparent)
painter = QtGui.QPainter(pixmap)
painter.setPen(QtCore.Qt.NoPen)
painter.setBrush(radialGrad)
painter.drawEllipse(0, 0, 60, 60)
painter.end()
self.m_lightSource = self.m_scene.addPixmap(pixmap)
self.m_lightSource.setZValue(2)
for i in range(-2, 3):
for j in range(-2, 3):
if (i + j) & 1:
item = QtWidgets.QGraphicsEllipseItem(0, 0, 50, 50)
else:
item = QtWidgets.QGraphicsRectItem(0, 0, 50, 50)
item.setPen(QtGui.QPen(QtCore.Qt.black, 1))
item.setBrush(QtGui.QBrush(QtCore.Qt.white))
effect = QtWidgets.QGraphicsDropShadowEffect(self)
effect.setBlurRadius(8)
item.setGraphicsEffect(effect)
item.setZValue(1)
item.setPos(i * 80, j * 80)
self.m_scene.addItem(item)
self.m_items.append(item)
def animate(self):
self.angle += (math.pi / 30)
xs = 200 * math.sin(self.angle) - 40 + 25
ys = 200 * math.cos(self.angle) - 40 + 25
self.m_lightSource.setPos(xs, ys)
for item in self.m_items:
effect = item.graphicsEffect()
delta = QtCore.QPointF(item.x() - xs, item.y() - ys)
effect.setOffset(QtCore.QPointF(delta.toPoint() / 30))
dd = math.hypot(delta.x(), delta.y())
color = effect.color()
color.setAlphaF(max(0.4, min(1 - dd / 200.0, 0.7)))
effect.setColor(color)
self.m_scene.update()
if __name__ == '__main__':
import sys
app = QtWidgets.QApplication(sys.argv)
lighting = Lighting()
lighting.setWindowTitle("Lighting and Shadows")
lighting.resize(640, 480)
lighting.show()
sys.exit(app.exec_())
© 2021 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners. The documentation provided herein is licensed under the terms of the GNU Free Documentation License version 1.3 as published by the Free Software Foundation. Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property of their respective owners.