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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "basictoolsplugin.h"
#include <QInputDialog>
#include <QPainter>
#include <QRandomGenerator>
#include <QtMath>
//! [0]
QStringList BasicToolsPlugin::brushes() const
{
return {tr("Pencil"), tr("Air Brush"), tr("Random Letters")};
}
//! [0]
//! [1]
QRect BasicToolsPlugin::mousePress(const QString &brush, QPainter &painter,
const QPoint &pos)
{
return mouseMove(brush, painter, pos, pos);
}
//! [1]
//! [2]
QRect BasicToolsPlugin::mouseMove(const QString &brush, QPainter &painter,
const QPoint &oldPos, const QPoint &newPos)
{
painter.save();
int rad = painter.pen().width() / 2;
QRect boundingRect = QRect(oldPos, newPos).normalized()
.adjusted(-rad, -rad, +rad, +rad);
QColor color = painter.pen().color();
int thickness = painter.pen().width();
QColor transparentColor(color.red(), color.green(), color.blue(), 0);
//! [2] //! [3]
if (brush == tr("Pencil")) {
painter.drawLine(oldPos, newPos);
} else if (brush == tr("Air Brush")) {
int numSteps = 2 + (newPos - oldPos).manhattanLength() / 2;
painter.setBrush(QBrush(color, Qt::Dense6Pattern));
painter.setPen(Qt::NoPen);
for (int i = 0; i < numSteps; ++i) {
int x = oldPos.x() + i * (newPos.x() - oldPos.x()) / (numSteps - 1);
int y = oldPos.y() + i * (newPos.y() - oldPos.y()) / (numSteps - 1);
painter.drawEllipse(x - (thickness / 2), y - (thickness / 2),
thickness, thickness);
}
} else if (brush == tr("Random Letters")) {
QChar ch(QRandomGenerator::global()->bounded('A', 'Z' + 1));
QFont biggerFont = painter.font();
biggerFont.setBold(true);
biggerFont.setPointSize(biggerFont.pointSize() + thickness);
painter.setFont(biggerFont);
painter.drawText(newPos, QString(ch));
QFontMetrics metrics(painter.font());
boundingRect = metrics.boundingRect(ch);
boundingRect.translate(newPos);
boundingRect.adjust(-10, -10, +10, +10);
}
painter.restore();
return boundingRect;
}
//! [3]
//! [4]
QRect BasicToolsPlugin::mouseRelease(const QString & /* brush */,
QPainter & /* painter */,
const QPoint & /* pos */)
{
return QRect(0, 0, 0, 0);
}
//! [4]
//! [5]
QStringList BasicToolsPlugin::shapes() const
{
return {tr("Circle"), tr("Star"), tr("Text...")};
}
//! [5]
//! [6]
QPainterPath BasicToolsPlugin::generateShape(const QString &shape,
QWidget *parent)
{
QPainterPath path;
if (shape == tr("Circle")) {
path.addEllipse(0, 0, 50, 50);
} else if (shape == tr("Star")) {
path.moveTo(90, 50);
for (int i = 1; i < 5; ++i) {
path.lineTo(50 + 40 * std::cos(0.8 * i * M_PI),
50 + 40 * std::sin(0.8 * i * M_PI));
}
path.closeSubpath();
} else if (shape == tr("Text...")) {
QString text = QInputDialog::getText(parent, tr("Text Shape"),
tr("Enter text:"),
QLineEdit::Normal, tr("Qt"));
if (!text.isEmpty()) {
QFont timesFont("Times", 50);
timesFont.setStyleStrategy(QFont::ForceOutline);
path.addText(0, 0, timesFont, text);
}
}
return path;
}
//! [6]
//! [7]
QStringList BasicToolsPlugin::filters() const
{
return {tr("Invert Pixels"), tr("Swap RGB"), tr("Grayscale")};
}
//! [7]
//! [8]
QImage BasicToolsPlugin::filterImage(const QString &filter, const QImage &image,
QWidget * /* parent */)
{
QImage result = image.convertToFormat(QImage::Format_RGB32);
if (filter == tr("Invert Pixels")) {
result.invertPixels();
} else if (filter == tr("Swap RGB")) {
result = result.rgbSwapped();
} else if (filter == tr("Grayscale")) {
for (int y = 0; y < result.height(); ++y) {
for (int x = 0; x < result.width(); ++x) {
QRgb pixel = result.pixel(x, y);
int gray = qGray(pixel);
int alpha = qAlpha(pixel);
result.setPixel(x, y, qRgba(gray, gray, gray, alpha));
}
}
}
return result;
}
//! [8]
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