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// 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);
}
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