summaryrefslogtreecommitdiffstats
path: root/examples/opengl/hellogl_es/bubble.cpp
blob: 9073db1c20e2fe481126335e765b9be6231c7fc2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/****************************************************************************
**
** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the examples of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** No Commercial Usage
** This file contains pre-release code and may not be distributed.
** You may use this file in accordance with the terms and conditions
** contained in the Technology Preview License Agreement accompanying
** this package.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL included in the
** packaging of this file.  Please review the following information to
** ensure the GNU Lesser General Public License version 2.1 requirements
** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain
** additional rights.  These rights are described in the Nokia Qt LGPL
** Exception version 1.1, included in the file LGPL_EXCEPTION.txt in this
** package.
**
** If you have questions regarding the use of this file, please contact
** Nokia at qt-info@nokia.com.
**
**
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include <QtGui>

#include "bubble.h"

Bubble::Bubble(const QPointF &position, qreal radius, const QPointF &velocity)
    : position(position), vel(velocity), radius(radius)
{
    innerColor = randomColor();
    outerColor = randomColor();
    cache = 0;
    updateBrush();
}

//! [0]
void Bubble::updateCache()
{
    if (cache)
        delete cache;
    cache = new QImage(qRound(radius * 2 + 2), qRound(radius * 2 + 2), QImage::Format_ARGB32);
    cache->fill(0x00000000);
    QPainter p(cache);
    p.setRenderHint(QPainter::HighQualityAntialiasing);
    QPen pen(Qt::white);
    pen.setWidth(2);
    p.setPen(pen);
    p.setBrush(brush);
    p.drawEllipse(0, 0, int(2*radius), int(2*radius));
}
//! [0]

Bubble::~Bubble()
{
    if (cache)
        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 + 70.0*qrand()/(RAND_MAX+1.0));
    int green = int(185 + 70.0*qrand()/(RAND_MAX+1.0));
    int blue = int(205 + 50.0*qrand()/(RAND_MAX+1.0));
    int alpha = int(91 + 100.0*qrand()/(RAND_MAX+1.0));

    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);
}