2 files changed, 150 insertions, 0 deletions
diff --git a/examples/widgets/effects/lighting/lighting.py b/examples/widgets/effects/lighting/lighting.py
new file mode 100644
index 000000000..ec8f945e1
--- /dev/null
+++ b/examples/widgets/effects/lighting/lighting.py
@@ -0,0 +1,147 @@
+
+#############################################################################
+##
+## Copyright (C) 2013 Riverbank Computing Limited.
+## Copyright (C) 2021 The Qt Company Ltd.
+## Contact: http://www.qt.io/licensing/
+##
+## This file is part of the Qt for Python examples of the Qt Toolkit.
+##
+## $QT_BEGIN_LICENSE:BSD$
+## You may use this file under the terms of the BSD license as follows:
+##
+## "Redistribution and use in source and binary forms, with or without
+## modification, are permitted provided that the following conditions are
+## met:
+##   * Redistributions of source code must retain the above copyright
+##     notice, this list of conditions and the following disclaimer.
+##   * Redistributions in binary form must reproduce the above copyright
+##     notice, this list of conditions and the following disclaimer in
+##     the documentation and/or other materials provided with the
+##     distribution.
+##   * Neither the name of The Qt Company Ltd nor the names of its
+##     contributors may be used to endorse or promote products derived
+##     from this software without specific prior written permission.
+##
+##
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+import math
+import sys
+
+from PySide6.QtCore import QPointF, QTimer, Qt
+from PySide6.QtGui import (QBrush, QColor, QLinearGradient, QPainter, QPen,
+                           QPixmap, QRadialGradient)
+from PySide6.QtWidgets import (QApplication, QFrame, QGraphicsDropShadowEffect,
+                               QGraphicsEllipseItem, QGraphicsRectItem,
+                               QGraphicsScene, QGraphicsView, QWidget)
+
+
+class Lighting(QGraphicsView):
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        self.angle = 0.0
+        self.m_scene = QGraphicsScene()
+        self.m_lightSource = None
+        self.m_items = []
+
+        self.setScene(self.m_scene)
+
+        self.setup_scene()
+
+        timer = QTimer(self)
+        timer.timeout.connect(self.animate)
+        timer.setInterval(30)
+        timer.start()
+
+        self.setRenderHint(QPainter.Antialiasing)
+        self.setFrameStyle(QFrame.NoFrame)
+
+    def setup_scene(self):
+        self.m_scene.setSceneRect(-300, -200, 600, 460)
+
+        linear_grad = QLinearGradient(QPointF(-100, -100),
+                QPointF(100, 100))
+        linear_grad.setColorAt(0, QColor(255, 255, 255))
+        linear_grad.setColorAt(1, QColor(192, 192, 255))
+        self.setBackgroundBrush(linear_grad)
+
+        radial_grad = QRadialGradient(30, 30, 30)
+        radial_grad.setColorAt(0, Qt.yellow)
+        radial_grad.setColorAt(0.2, Qt.yellow)
+        radial_grad.setColorAt(1, Qt.transparent)
+
+        pixmap = QPixmap(60, 60)
+        pixmap.fill(Qt.transparent)
+
+        painter = QPainter(pixmap)
+        painter.setPen(Qt.NoPen)
+        painter.setBrush(radial_grad)
+        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 = QGraphicsEllipseItem(0, 0, 50, 50)
+                else:
+                    item = QGraphicsRectItem(0, 0, 50, 50)
+
+                item.setPen(QPen(Qt.black, 1))
+                item.setBrush(QBrush(Qt.white))
+
+                effect = 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 = QPointF(item.x() - xs, item.y() - ys)
+            effect.setOffset(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__':
+    app = QApplication(sys.argv)
+
+    lighting = Lighting()
+    lighting.setWindowTitle("Lighting and Shadows")
+    lighting.resize(640, 480)
+    lighting.show()
+
+    sys.exit(app.exec())
diff --git a/examples/widgets/effects/lighting/lighting.pyproject b/examples/widgets/effects/lighting/lighting.pyproject
new file mode 100644
index 000000000..c64fe46d4
--- /dev/null
+++ b/examples/widgets/effects/lighting/lighting.pyproject
@@ -0,0 +1,3 @@
+{
+    "files": ["lighting.py"]
+}