Add blurpicker example

Ported from C++

Change-Id: Id18068e36ecfa26ab0312cfde2de1ba1c0773223
Task-number: PYSIDE-841
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

16 files changed, 308 insertions, 0 deletions

diff --git a/examples/widgets/effects/blurpicker/blureffect.py b/examples/widgets/effects/blurpicker/blureffect.py
new file mode 100644
index 000000000..6aeb7074c
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/blureffect.py
@@ -0,0 +1,70 @@
+#############################################################################
+##
+## 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."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+
+from PySide6.QtCore import QRect
+from PySide6.QtGui import QPainter
+from PySide6.QtWidgets import QGraphicsBlurEffect
+
+
+class BlurEffect(QGraphicsBlurEffect):
+    def __init__(self, item):
+        super().__init__()
+        self.m_base_line = 200
+        self.item = item
+
+    def adjust_for_item(self):
+        y = self.m_base_line - self.item.pos().y()
+
+        # radius = qBound(qreal(0.0), y / 32, qreal(16.0)); which is equivalent to
+        radius = max(0, min(y / 32, 16))
+
+        self.setBlurRadius(radius)
+
+    def set_base_line(self, base_line):
+        self.m_base_line = base_line
+
+    def boundingRect(self) -> QRect:
+        self.adjust_for_item()
+        return super().boundingRect()
+
+    def draw(self, painter: QPainter):
+        self.adjust_for_item()
+        super().draw(painter)
diff --git a/examples/widgets/effects/blurpicker/blurpicker.py b/examples/widgets/effects/blurpicker/blurpicker.py
new file mode 100644
index 000000000..560a6dcad
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/blurpicker.py
@@ -0,0 +1,151 @@
+#############################################################################
+##
+## 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."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+
+from pathlib import Path
+from PySide6.QtCore import (
+    QEasingCurve,
+    QPointF,
+    Qt,
+    QAbstractAnimation,
+    QPropertyAnimation,
+    Property,
+)
+from PySide6.QtGui import QPainter, QTransform, QPixmap
+from PySide6.QtWidgets import QGraphicsView, QFrame, QGraphicsScene, QGraphicsPixmapItem
+from math import pi, sin, cos
+from blureffect import BlurEffect
+
+
+class BlurPicker(QGraphicsView):
+    def __init__(self, parent=None):
+        super().__init__(parent)
+        self.m_index = 0
+        self.m_animation = QPropertyAnimation(self, b"index")
+        self.path = Path(__file__).resolve().parent
+
+        self.setBackgroundBrush(QPixmap(self.path / "images" / "background.jpg"))
+        self.setScene(QGraphicsScene(self))
+
+        self.m_icons = []
+
+        self.setup_scene()
+        self.set_index(0)
+
+        self.m_animation.setDuration(400)
+        self.m_animation.setEasingCurve(QEasingCurve.InOutSine)
+
+        self.setRenderHint(QPainter.Antialiasing, True)
+        self.setFrameStyle(QFrame.NoFrame)
+
+    def read_index(self) -> float:
+        return self.m_index
+
+    def set_index(self, index: float):
+        self.m_index = index
+
+        base_line = 0.0
+        iconAngle = 2 * pi / len(self.m_icons)
+
+        for i, icon in enumerate(self.m_icons):
+            a = (i + self.m_index) * iconAngle
+            xs = 170 * sin(a)
+            ys = 100 * cos(a)
+            pos = QPointF(xs, ys)
+            pos = QTransform().rotate(-20).map(pos)
+            pos -= QPointF(40, 40)
+            icon.setPos(pos)
+            base_line = max(base_line, ys)
+
+            icon.graphicsEffect().set_base_line(base_line)
+
+        self.scene().update()
+
+    def setup_scene(self):
+        self.scene().setSceneRect(-200, -120, 400, 240)
+
+        names = [
+            self.path / "images" / "accessories-calculator.png",
+            self.path / "images" / "accessories-text-editor.png",
+            self.path / "images" / "help-browser.png",
+            self.path / "images" / "internet-group-chat.png",
+            self.path / "images" / "internet-mail.png",
+            self.path / "images" / "internet-web-browser.png",
+            self.path / "images" / "office-calendar.png",
+            self.path / "images" / "system-users.png",
+        ]
+
+        for name in names:
+            pixmap = QPixmap(name)
+            icon: QGraphicsPixmapItem = self.scene().addPixmap(pixmap)
+            icon.setZValue(1)
+            icon.setGraphicsEffect(BlurEffect(icon))
+            self.m_icons.append(icon)
+
+        bg: QGraphicsPixmapItem = self.scene().addPixmap(
+            QPixmap(self.path / "images" / "background.jpg")
+        )
+        bg.setZValue(0)
+        bg.setPos(-200, -150)
+
+    def keyPressEvent(self, event):
+        delta = 0
+        if event.key() == Qt.Key_Left:
+            delta = -1
+        elif event.key() == Qt.Key_Right:
+            delta = 1
+
+        if self.m_animation.state() == QAbstractAnimation.Stopped and delta:
+            self.m_animation.setEndValue(self.m_index + delta)
+            self.m_animation.start()
+            event.accept()
+
+    def mousePressEvent(self, event):
+        if event.position().x() > (self.width() / 2):
+            delta = 1
+        else:
+            delta = -1
+
+        if self.m_animation.state() == QAbstractAnimation.Stopped:
+            self.m_animation.setEndValue(self.m_index + delta)
+            self.m_animation.start()
+            event.accept()
+
+    index = Property(float, read_index, set_index)
diff --git a/examples/widgets/effects/blurpicker/blurpicker.pyproject b/examples/widgets/effects/blurpicker/blurpicker.pyproject
new file mode 100644
index 000000000..b29f49499
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/blurpicker.pyproject
@@ -0,0 +1,16 @@
+{
+    "files": [
+        "blurpicker.py",
+        "blureffect.py",
+        "images/accessories-calculator.png",
+        "images/accessories-text-editor.png",
+        "images/background.jpg",
+        "images/help-browser.png",
+        "images/internet-group-chat.png",
+        "images/internet-mail.png",
+        "images/internet-web-browser.png",
+        "images/office-calendar.png",
+        "images/README.txt",
+        "images/system-users.png",
+    ]
+}
diff --git a/examples/widgets/effects/blurpicker/doc/blurpicker.png b/examples/widgets/effects/blurpicker/doc/blurpicker.png
new file mode 100644
index 000000000..826eef201
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/doc/blurpicker.png
diff --git a/examples/widgets/effects/blurpicker/doc/blurpicker.rst b/examples/widgets/effects/blurpicker/doc/blurpicker.rst
new file mode 100644
index 000000000..70ce04c8d
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/doc/blurpicker.rst
@@ -0,0 +1,9 @@
+Blur Picker Effect Example
+==========================
+
+The blur picker effect example demonstrates how to apply
+graphical effects on items in the view.
+
+.. image:: blurpicker.png
+   :width: 400
+   :alt: Blur Picker Screenshot
diff --git a/examples/widgets/effects/blurpicker/images/README.txt b/examples/widgets/effects/blurpicker/images/README.txt
new file mode 100644
index 000000000..0927e177d
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/README.txt
@@ -0,0 +1,5 @@
+The background is taken from a public domain photo at:
+http://www.photos8.com/view/computer_board2-800x600.html
+
+All other icons are from the Tango Desktop project:
+http://tango.freedesktop.org/Tango_Desktop_Project
diff --git a/examples/widgets/effects/blurpicker/images/accessories-calculator.png b/examples/widgets/effects/blurpicker/images/accessories-calculator.png
new file mode 100644
index 000000000..4e7661f65
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/accessories-calculator.png
diff --git a/examples/widgets/effects/blurpicker/images/accessories-text-editor.png b/examples/widgets/effects/blurpicker/images/accessories-text-editor.png
new file mode 100644
index 000000000..33bef0bc1
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/accessories-text-editor.png
diff --git a/examples/widgets/effects/blurpicker/images/background.jpg b/examples/widgets/effects/blurpicker/images/background.jpg
new file mode 100644
index 000000000..e75b38899
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/background.jpg
diff --git a/examples/widgets/effects/blurpicker/images/help-browser.png b/examples/widgets/effects/blurpicker/images/help-browser.png
new file mode 100644
index 000000000..8ef4fae91
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/help-browser.png
diff --git a/examples/widgets/effects/blurpicker/images/internet-group-chat.png b/examples/widgets/effects/blurpicker/images/internet-group-chat.png
new file mode 100644
index 000000000..dd92d9394
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/internet-group-chat.png
diff --git a/examples/widgets/effects/blurpicker/images/internet-mail.png b/examples/widgets/effects/blurpicker/images/internet-mail.png
new file mode 100644
index 000000000..7e6b93be8
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/internet-mail.png
diff --git a/examples/widgets/effects/blurpicker/images/internet-web-browser.png b/examples/widgets/effects/blurpicker/images/internet-web-browser.png
new file mode 100644
index 000000000..a979a92b4
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/internet-web-browser.png
diff --git a/examples/widgets/effects/blurpicker/images/office-calendar.png b/examples/widgets/effects/blurpicker/images/office-calendar.png
new file mode 100644
index 000000000..e09590682
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/office-calendar.png
diff --git a/examples/widgets/effects/blurpicker/images/system-users.png b/examples/widgets/effects/blurpicker/images/system-users.png
new file mode 100644
index 000000000..a7f630a5b
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/images/system-users.png
diff --git a/examples/widgets/effects/blurpicker/main.py b/examples/widgets/effects/blurpicker/main.py
new file mode 100644
index 000000000..8bd708fbe
--- /dev/null
+++ b/examples/widgets/effects/blurpicker/main.py
@@ -0,0 +1,57 @@
+#############################################################################
+##
+## 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."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+"""PySide6 Multimedia Camera Example"""
+
+import sys
+from PySide6.QtWidgets import QApplication
+from blurpicker import BlurPicker
+
+
+if __name__ == "__main__":
+    app = QApplication(sys.argv)
+
+    blur_picker = BlurPicker()
+    blur_picker.setWindowTitle("Application Picker")
+
+    blur_picker.setFixedSize(400, 300)
+    blur_picker.show()
+
+    sys.exit(app.exec())