1/****************************************************************************
2**
3** Copyright (C) 2016 The Qt Company Ltd.
4** Contact: https://www.qt.io/licensing/
5**
6** This file is part of the examples of the Qt Toolkit.
7**
8** $QT_BEGIN_LICENSE:BSD$
9** Commercial License Usage
10** Licensees holding valid commercial Qt licenses may use this file in
11** accordance with the commercial license agreement provided with the
12** Software or, alternatively, in accordance with the terms contained in
13** a written agreement between you and The Qt Company. For licensing terms
14** and conditions see https://www.qt.io/terms-conditions. For further
15** information use the contact form at https://www.qt.io/contact-us.
16**
17** BSD License Usage
18** Alternatively, you may use this file under the terms of the BSD license
19** as follows:
20**
21** "Redistribution and use in source and binary forms, with or without
22** modification, are permitted provided that the following conditions are
23** met:
24** * Redistributions of source code must retain the above copyright
25** notice, this list of conditions and the following disclaimer.
26** * Redistributions in binary form must reproduce the above copyright
27** notice, this list of conditions and the following disclaimer in
28** the documentation and/or other materials provided with the
29** distribution.
30** * Neither the name of The Qt Company Ltd nor the names of its
31** contributors may be used to endorse or promote products derived
32** from this software without specific prior written permission.
33**
34**
35** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
36** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
37** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
38** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
39** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
40** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
41** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
42** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
43** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
44** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
45** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
46**
47** $QT_END_LICENSE$
48**
49****************************************************************************/
50
51#include "imagecomposer.h"
52
53#include <QtWidgets>
54
55//! [0]
56static const QSize resultSize(200, 200);
57//! [0]
58
59//! [1]
60ImageComposer::ImageComposer()
61{
62 sourceButton = new QToolButton;
63 sourceButton->setIconSize(resultSize);
64
65 operatorComboBox = new QComboBox;
66 addOp(mode: QPainter::CompositionMode_SourceOver, name: tr(s: "SourceOver"));
67 addOp(mode: QPainter::CompositionMode_DestinationOver, name: tr(s: "DestinationOver"));
68 addOp(mode: QPainter::CompositionMode_Clear, name: tr(s: "Clear"));
69 addOp(mode: QPainter::CompositionMode_Source, name: tr(s: "Source"));
70 addOp(mode: QPainter::CompositionMode_Destination, name: tr(s: "Destination"));
71 addOp(mode: QPainter::CompositionMode_SourceIn, name: tr(s: "SourceIn"));
72 addOp(mode: QPainter::CompositionMode_DestinationIn, name: tr(s: "DestinationIn"));
73 addOp(mode: QPainter::CompositionMode_SourceOut, name: tr(s: "SourceOut"));
74 addOp(mode: QPainter::CompositionMode_DestinationOut, name: tr(s: "DestinationOut"));
75 addOp(mode: QPainter::CompositionMode_SourceAtop, name: tr(s: "SourceAtop"));
76 addOp(mode: QPainter::CompositionMode_DestinationAtop, name: tr(s: "DestinationAtop"));
77 addOp(mode: QPainter::CompositionMode_Xor, name: tr(s: "Xor"));
78 addOp(mode: QPainter::CompositionMode_Plus, name: tr(s: "Plus"));
79 addOp(mode: QPainter::CompositionMode_Multiply, name: tr(s: "Multiply"));
80 addOp(mode: QPainter::CompositionMode_Screen, name: tr(s: "Screen"));
81 addOp(mode: QPainter::CompositionMode_Overlay, name: tr(s: "Overlay"));
82 addOp(mode: QPainter::CompositionMode_Darken, name: tr(s: "Darken"));
83 addOp(mode: QPainter::CompositionMode_Lighten, name: tr(s: "Lighten"));
84 addOp(mode: QPainter::CompositionMode_ColorDodge, name: tr(s: "ColorDodge"));
85 addOp(mode: QPainter::CompositionMode_ColorBurn, name: tr(s: "ColorBurn"));
86 addOp(mode: QPainter::CompositionMode_HardLight, name: tr(s: "HardLight"));
87 addOp(mode: QPainter::CompositionMode_SoftLight, name: tr(s: "SoftLight"));
88 addOp(mode: QPainter::CompositionMode_Difference, name: tr(s: "Difference"));
89 addOp(mode: QPainter::CompositionMode_Exclusion, name: tr(s: "Exclusion"));
90//! [1]
91
92//! [2]
93 destinationButton = new QToolButton;
94 destinationButton->setIconSize(resultSize);
95
96 equalLabel = new QLabel(tr(s: "="));
97
98 resultLabel = new QLabel;
99 resultLabel->setMinimumWidth(resultSize.width());
100//! [2]
101
102//! [3]
103 connect(sender: sourceButton, signal: &QAbstractButton::clicked,
104 receiver: this, slot: &ImageComposer::chooseSource);
105 connect(sender: operatorComboBox, signal: QOverload<int>::of(ptr: &QComboBox::activated),
106 receiver: this, slot: &ImageComposer::recalculateResult);
107 connect(sender: destinationButton, signal: &QAbstractButton::clicked,
108 receiver: this, slot: &ImageComposer::chooseDestination);
109//! [3]
110
111//! [4]
112 QGridLayout *mainLayout = new QGridLayout;
113 mainLayout->addWidget(sourceButton, row: 0, column: 0, rowSpan: 3, columnSpan: 1);
114 mainLayout->addWidget(operatorComboBox, row: 1, column: 1);
115 mainLayout->addWidget(destinationButton, row: 0, column: 2, rowSpan: 3, columnSpan: 1);
116 mainLayout->addWidget(equalLabel, row: 1, column: 3);
117 mainLayout->addWidget(resultLabel, row: 0, column: 4, rowSpan: 3, columnSpan: 1);
118 mainLayout->setSizeConstraint(QLayout::SetFixedSize);
119 setLayout(mainLayout);
120//! [4]
121
122//! [5]
123 resultImage = QImage(resultSize, QImage::Format_ARGB32_Premultiplied);
124
125 loadImage(fileName: ":/images/butterfly.png", image: &sourceImage, button: sourceButton);
126 loadImage(fileName: ":/images/checker.png", image: &destinationImage, button: destinationButton);
127
128 setWindowTitle(tr(s: "Image Composition"));
129}
130//! [5]
131
132//! [6]
133void ImageComposer::chooseSource()
134{
135 chooseImage(title: tr(s: "Choose Source Image"), image: &sourceImage, button: sourceButton);
136}
137//! [6]
138
139//! [7]
140void ImageComposer::chooseDestination()
141{
142 chooseImage(title: tr(s: "Choose Destination Image"), image: &destinationImage, button: destinationButton);
143}
144//! [7]
145
146//! [8]
147void ImageComposer::recalculateResult()
148{
149 QPainter::CompositionMode mode = currentMode();
150
151 QPainter painter(&resultImage);
152 painter.setCompositionMode(QPainter::CompositionMode_Source);
153 painter.fillRect(r: resultImage.rect(), c: Qt::transparent);
154 painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
155 painter.drawImage(x: 0, y: 0, image: destinationImage);
156 painter.setCompositionMode(mode);
157 painter.drawImage(x: 0, y: 0, image: sourceImage);
158 painter.setCompositionMode(QPainter::CompositionMode_DestinationOver);
159 painter.fillRect(r: resultImage.rect(), c: Qt::white);
160 painter.end();
161
162 resultLabel->setPixmap(QPixmap::fromImage(image: resultImage));
163}
164//! [8]
165
166//! [9]
167void ImageComposer::addOp(QPainter::CompositionMode mode, const QString &name)
168{
169 operatorComboBox->addItem(atext: name, auserData: mode);
170}
171//! [9]
172
173//! [10]
174void ImageComposer::chooseImage(const QString &title, QImage *image,
175 QToolButton *button)
176{
177 QString fileName = QFileDialog::getOpenFileName(parent: this, caption: title);
178 if (!fileName.isEmpty())
179 loadImage(fileName, image, button);
180}
181//! [10]
182
183//! [11]
184void ImageComposer::loadImage(const QString &fileName, QImage *image,
185 QToolButton *button)
186{
187 image->load(fileName);
188
189 // Scale the image to given size
190 *image = image->scaled(s: resultSize, aspectMode: Qt::KeepAspectRatio);
191
192 QImage fixedImage(resultSize, QImage::Format_ARGB32_Premultiplied);
193 QPainter painter(&fixedImage);
194 painter.setCompositionMode(QPainter::CompositionMode_Source);
195 painter.fillRect(r: fixedImage.rect(), c: Qt::transparent);
196 painter.setCompositionMode(QPainter::CompositionMode_SourceOver);
197 painter.drawImage(p: imagePos(image: *image), image: *image);
198 painter.end();
199 button->setIcon(QPixmap::fromImage(image: fixedImage));
200
201 *image = fixedImage;
202
203 recalculateResult();
204}
205//! [11]
206
207//! [12]
208QPainter::CompositionMode ImageComposer::currentMode() const
209{
210 return (QPainter::CompositionMode)
211 operatorComboBox->itemData(index: operatorComboBox->currentIndex()).toInt();
212}
213//! [12]
214
215//! [13]
216QPoint ImageComposer::imagePos(const QImage &image) const
217{
218 return QPoint((resultSize.width() - image.width()) / 2,
219 (resultSize.height() - image.height()) / 2);
220}
221//! [13]
222

source code of qtbase/examples/widgets/painting/imagecomposition/imagecomposer.cpp