1 files changed, 99 insertions, 0 deletions
diff --git a/tests/manual/examples/opengl/qopenglwidget/bubble.cpp b/tests/manual/examples/opengl/qopenglwidget/bubble.cpp
new file mode 100644
index 0000000000..3c32b62113
--- /dev/null
+++ b/tests/manual/examples/opengl/qopenglwidget/bubble.cpp
@@ -0,0 +1,99 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+
+#include <QtWidgets>
+
+#include "bubble.h"
+
+Bubble::Bubble(const QPointF &position, qreal radius, const QPointF &velocity)
+    : position(position), vel(velocity), radius(radius)
+{
+    innerColor = randomColor();
+    outerColor = randomColor();
+    updateBrush();
+}
+
+//! [0]
+void Bubble::updateCache()
+{
+    delete cache;
+    cache = new QImage(qRound(radius * 2 + 2), qRound(radius * 2 + 2), QImage::Format_ARGB32_Premultiplied);
+    cache->fill(0x00000000);
+    QPainter p(cache);
+    p.setRenderHint(QPainter::Antialiasing);
+    QPen pen(Qt::white);
+    pen.setWidth(2);
+    p.setPen(pen);
+    p.setBrush(brush);
+    p.drawEllipse(1, 1, int(2*radius), int(2*radius));
+}
+//! [0]
+
+Bubble::~Bubble()
+{
+    delete cache;
+}
+
+void Bubble::updateBrush()
+{
+    QRadialGradient gradient(QPointF(radius, radius), radius,
+                             QPointF(radius*0.5, radius*0.5));
+
+    gradient.setColorAt(0, QColor(255, 255, 255, 255));
+    gradient.setColorAt(0.25, innerColor);
+    gradient.setColorAt(1, outerColor);
+    brush = QBrush(gradient);
+    updateCache();
+}
+
+//! [1]
+void Bubble::drawBubble(QPainter *painter)
+{
+    painter->save();
+    painter->translate(position.x() - radius, position.y() - radius);
+    painter->setOpacity(0.8);
+    painter->drawImage(0, 0, *cache);
+    painter->restore();
+}
+//! [1]
+
+QColor Bubble::randomColor()
+{
+    int red = int(185 + QRandomGenerator::global()->bounded(70));
+    int green = int(185 + QRandomGenerator::global()->bounded(70));
+    int blue = int(205 + QRandomGenerator::global()->bounded(50));
+    int alpha = int(91 + QRandomGenerator::global()->bounded(100));
+
+    return QColor(red, green, blue, alpha);
+}
+
+void Bubble::move(const QRect &bbox)
+{
+    position += vel;
+    qreal leftOverflow = position.x() - radius - bbox.left();
+    qreal rightOverflow = position.x() + radius - bbox.right();
+    qreal topOverflow = position.y() - radius - bbox.top();
+    qreal bottomOverflow = position.y() + radius - bbox.bottom();
+
+    if (leftOverflow < 0.0) {
+        position.setX(position.x() - 2 * leftOverflow);
+        vel.setX(-vel.x());
+    } else if (rightOverflow > 0.0) {
+        position.setX(position.x() - 2 * rightOverflow);
+        vel.setX(-vel.x());
+    }
+
+    if (topOverflow < 0.0) {
+        position.setY(position.y() - 2 * topOverflow);
+        vel.setY(-vel.y());
+    } else if (bottomOverflow > 0.0) {
+        position.setY(position.y() - 2 * bottomOverflow);
+        vel.setY(-vel.y());
+    }
+}
+
+QRectF Bubble::rect()
+{
+    return QRectF(position.x() - radius, position.y() - radius,
+                  2 * radius, 2 * radius);
+}