pathstroke.cpp Example File
demos/pathstroke/pathstroke.cpp
/****************************************************************************
**
** Copyright (C) 2005-2005 Trolltech AS. All rights reserved.
**
** This file is part of the documentation of the Qt Toolkit.
**
** This file may be used under the terms of the GNU General Public
** License version 2.0 as published by the Free Software Foundation
** and appearing in the file LICENSE.GPL included in the packaging of
** this file. Please review the following information to ensure GNU
** General Public Licensing requirements will be met:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
** http://www.trolltech.com/products/qt/licensing.html or contact the
** sales department at sales@trolltech.com.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
****************************************************************************/
#include "pathstroke.h"
#include "arthurstyle.h"
#include "arthurwidgets.h"
extern void draw_round_rect(QPainter *p, const QRect &bounds, int radius);
PathStrokeWidget::PathStrokeWidget()
{
setWindowTitle(tr("Path Stroking"));
// Setting up palette.
QPalette pal = palette();
// pal.setBrush(QPalette::Background, Qt::white);
// pal.setBrush(QPalette::Foreground, QColor("aquamarine"));
// pal.setBrush(QPalette::Background, QPixmap("background.png"));
setPalette(pal);
// Widget construction and property setting
m_renderer = new PathStrokeRenderer(this);
QGroupBox *mainGroup = new QGroupBox(this);
// QWidget *mainGroup = new QWidget(this);
mainGroup->setFixedWidth(180);
mainGroup->setTitle("Path Stroking");
QGroupBox *capGroup = new QGroupBox(mainGroup);
capGroup->setAttribute(Qt::WA_ContentsPropagated);
QRadioButton *flatCap = new QRadioButton(capGroup);
QRadioButton *squareCap = new QRadioButton(capGroup);
QRadioButton *roundCap = new QRadioButton(capGroup);
capGroup->setTitle("Cap Style");
flatCap->setText("Flat Cap");
squareCap->setText("Square Cap");
roundCap->setText("Round Cap");
QGroupBox *joinGroup = new QGroupBox(mainGroup);
joinGroup->setAttribute(Qt::WA_ContentsPropagated);
QRadioButton *bevelJoin = new QRadioButton(joinGroup);
QRadioButton *miterJoin = new QRadioButton(joinGroup);
QRadioButton *roundJoin = new QRadioButton(joinGroup);
joinGroup->setTitle("Join Style");
bevelJoin->setText("Bevel Join");
miterJoin->setText("Miter Join");
roundJoin->setText("Round Join");
QGroupBox *styleGroup = new QGroupBox(mainGroup);
styleGroup->setAttribute(Qt::WA_ContentsPropagated);
QRadioButton *solidLine = new QRadioButton(styleGroup);
QRadioButton *dashLine = new QRadioButton(styleGroup);
QRadioButton *dotLine = new QRadioButton(styleGroup);
QRadioButton *dashDotLine = new QRadioButton(styleGroup);
QRadioButton *dashDotDotLine = new QRadioButton(styleGroup);
QRadioButton *customDashLine = new QRadioButton(styleGroup);
styleGroup->setTitle("Pen Style");
#if 0
solidLine->setText("Solid Line");
dashLine->setText("Dash Line");
dotLine->setText("Dot Line");
dashDotLine->setText("Dash Dot Line");
dashDotDotLine->setText("Dash Dot Dot Line");
#else
solidLine->setIcon(QPixmap(":res/images/line_solid.png"));
dashLine->setIcon(QPixmap(":res/images/line_dashed.png"));
dotLine->setIcon(QPixmap(":res/images/line_dotted.png"));
dashDotLine->setIcon(QPixmap(":res/images/line_dash_dot.png"));
dashDotDotLine->setIcon(QPixmap(":res/images/line_dash_dot_dot.png"));
customDashLine->setText("Custom Style");
int fixedHeight = bevelJoin->sizeHint().height();
solidLine->setFixedHeight(fixedHeight);
dashLine->setFixedHeight(fixedHeight);
dotLine->setFixedHeight(fixedHeight);
dashDotLine->setFixedHeight(fixedHeight);
dashDotDotLine->setFixedHeight(fixedHeight);
#endif
QGroupBox *pathModeGroup = new QGroupBox(mainGroup);
pathModeGroup->setAttribute(Qt::WA_ContentsPropagated);
QRadioButton *curveMode = new QRadioButton(pathModeGroup);
QRadioButton *lineMode = new QRadioButton(pathModeGroup);
pathModeGroup->setTitle("Path composed of");
curveMode->setText("Curves");
lineMode->setText("Lines");
QGroupBox *penWidthGroup = new QGroupBox(mainGroup);
penWidthGroup->setAttribute(Qt::WA_ContentsPropagated);
QSlider *penWidth = new QSlider(Qt::Horizontal, penWidthGroup);
penWidth->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
penWidthGroup->setTitle("Pen Width");
penWidth->setRange(0, 500);
#if 0
QCheckBox *animated = new QCheckBox(mainGroup);
animated->setText("Animated");
#else
QPushButton *animated = new QPushButton(mainGroup);
animated->setText("Animate");
animated->setCheckable(true);
#endif
QPushButton *showSourceButton = new QPushButton(mainGroup);
showSourceButton->setText("Show Source");
QPushButton *whatsThisButton = new QPushButton(mainGroup);
whatsThisButton->setText("What's This?");
whatsThisButton->setCheckable(true);
// Layouting
QHBoxLayout *viewLayout = new QHBoxLayout(this);
viewLayout->addWidget(m_renderer);
viewLayout->addWidget(mainGroup);
QVBoxLayout *mainGroupLayout = new QVBoxLayout(mainGroup);
mainGroupLayout->setMargin(3);
mainGroupLayout->addWidget(capGroup);
mainGroupLayout->addWidget(joinGroup);
mainGroupLayout->addWidget(styleGroup);
mainGroupLayout->addWidget(penWidthGroup);
mainGroupLayout->addWidget(pathModeGroup);
mainGroupLayout->addWidget(animated);
mainGroupLayout->addStretch(1);
mainGroupLayout->addWidget(showSourceButton);
mainGroupLayout->addWidget(whatsThisButton);
QVBoxLayout *capGroupLayout = new QVBoxLayout(capGroup);
capGroupLayout->addWidget(flatCap);
capGroupLayout->addWidget(squareCap);
capGroupLayout->addWidget(roundCap);
QVBoxLayout *joinGroupLayout = new QVBoxLayout(joinGroup);
joinGroupLayout->addWidget(bevelJoin);
joinGroupLayout->addWidget(miterJoin);
joinGroupLayout->addWidget(roundJoin);
QVBoxLayout *styleGroupLayout = new QVBoxLayout(styleGroup);
styleGroupLayout->addWidget(solidLine);
styleGroupLayout->addWidget(dashLine);
styleGroupLayout->addWidget(dotLine);
styleGroupLayout->addWidget(dashDotLine);
styleGroupLayout->addWidget(dashDotDotLine);
styleGroupLayout->addWidget(customDashLine);
QVBoxLayout *pathModeGroupLayout = new QVBoxLayout(pathModeGroup);
pathModeGroupLayout->addWidget(curveMode);
pathModeGroupLayout->addWidget(lineMode);
QVBoxLayout *penWidthLayout = new QVBoxLayout(penWidthGroup);
penWidthLayout->addWidget(penWidth);
// Set up connections
connect(penWidth, SIGNAL(valueChanged(int)),
m_renderer, SLOT(setPenWidth(int)));
connect(animated, SIGNAL(toggled(bool)),
m_renderer, SLOT(setAnimation(bool)));
connect(flatCap, SIGNAL(clicked()), m_renderer, SLOT(setFlatCap()));
connect(squareCap, SIGNAL(clicked()), m_renderer, SLOT(setSquareCap()));
connect(roundCap, SIGNAL(clicked()), m_renderer, SLOT(setRoundCap()));
connect(bevelJoin, SIGNAL(clicked()), m_renderer, SLOT(setBevelJoin()));
connect(miterJoin, SIGNAL(clicked()), m_renderer, SLOT(setMiterJoin()));
connect(roundJoin, SIGNAL(clicked()), m_renderer, SLOT(setRoundJoin()));
connect(curveMode, SIGNAL(clicked()), m_renderer, SLOT(setCurveMode()));
connect(lineMode, SIGNAL(clicked()), m_renderer, SLOT(setLineMode()));
connect(solidLine, SIGNAL(clicked()), m_renderer, SLOT(setSolidLine()));
connect(dashLine, SIGNAL(clicked()), m_renderer, SLOT(setDashLine()));
connect(dotLine, SIGNAL(clicked()), m_renderer, SLOT(setDotLine()));
connect(dashDotLine, SIGNAL(clicked()), m_renderer, SLOT(setDashDotLine()));
connect(dashDotDotLine, SIGNAL(clicked()), m_renderer, SLOT(setDashDotDotLine()));
connect(customDashLine, SIGNAL(clicked()), m_renderer, SLOT(setCustomDashLine()));
connect(showSourceButton, SIGNAL(clicked()), m_renderer, SLOT(showSource()));
connect(whatsThisButton, SIGNAL(clicked(bool)), m_renderer, SLOT(setDescriptionEnabled(bool)));
connect(m_renderer, SIGNAL(descriptionEnabledChanged(bool)),
whatsThisButton, SLOT(setChecked(bool)));
// Set the defaults
animated->setChecked(true);
flatCap->setChecked(true);
bevelJoin->setChecked(true);
penWidth->setValue(50);
curveMode->setChecked(true);
solidLine->setChecked(true);
m_renderer->loadSourceFile(":res/pathstroke.cpp");
m_renderer->loadDescription(":res/pathstroke.html");
}
PathStrokeRenderer::PathStrokeRenderer(QWidget *parent)
: ArthurFrame(parent)
{
m_pointSize = 10;
m_activePoint = -1;
m_capStyle = Qt::FlatCap;
m_joinStyle = Qt::BevelJoin;
m_pathMode = CurveMode;
m_penWidth = 1;
m_penStyle = Qt::SolidLine;
m_wasAnimated = true;
setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
}
void PathStrokeRenderer::paint(QPainter *painter)
{
if (m_points.isEmpty())
initializePoints();
painter->setRenderHint(QPainter::Antialiasing);
QPalette pal = palette();
painter->setPen(Qt::NoPen);
// Construct the path
QPainterPath path;
path.moveTo(m_points.at(0));
if (m_pathMode == LineMode) {
for (int i=1; i<m_points.size(); ++i) {
path.lineTo(m_points.at(i));
}
} else {
int i=1;
while (i + 2 < m_points.size()) {
path.cubicTo(m_points.at(i), m_points.at(i+1), m_points.at(i+2));
i += 3;
}
while (i < m_points.size()) {
path.lineTo(m_points.at(i));
++i;
}
}
// Draw the path
{
QColor lg = Qt::red;
// The "custom" pen
if (m_penStyle == Qt::NoPen) {
QPainterPathStroker stroker;
stroker.setWidth(m_penWidth);
stroker.setJoinStyle(m_joinStyle);
stroker.setCapStyle(m_capStyle);
QVector<qreal> dashes;
qreal space = 4;
dashes << 1 << space
<< 3 << space
<< 9 << space
<< 27 << space
<< 9 << space
<< 3 << space;
stroker.setDashPattern(dashes);
QPainterPath stroke = stroker.createStroke(path);
painter->fillPath(stroke, lg);
} else {
QPen pen(lg, m_penWidth, m_penStyle, m_capStyle, m_joinStyle);
painter->strokePath(path, pen);
}
}
if (1) {
// Draw the control points
painter->setPen(QColor(50, 100, 120, 200));
painter->setBrush(QColor(200, 200, 210, 120));
for (int i=0; i<m_points.size(); ++i) {
QPointF pos = m_points.at(i);
painter->drawEllipse(QRectF(pos.x() - m_pointSize,
pos.y() - m_pointSize,
m_pointSize*2, m_pointSize*2));
}
painter->setPen(QPen(Qt::lightGray, 0, Qt::SolidLine));
painter->setBrush(Qt::NoBrush);
painter->drawPolyline(m_points);
}
}
void PathStrokeRenderer::initializePoints()
{
const int count = 7;
m_points.clear();
m_vectors.clear();
QMatrix m;
double rot = 360 / count;
QPointF center(width() / 2, height() / 2);
QMatrix vm;
vm.shear(2, -1);
vm.scale(3, 3);
for (int i=0; i<count; ++i) {
m_vectors << QPointF(.1f, .25f) * (m * vm);
m_points << QPointF(0, 100) * m + center;
m.rotate(rot);
}
}
void PathStrokeRenderer::updatePoints()
{
double pad = 10;
double left = pad;
double right = width() - pad;
double top = pad;
double bottom = height() - pad;
Q_ASSERT(m_points.size() == m_vectors.size());
for (int i=0; i<m_points.size(); ++i) {
if (i == m_activePoint)
continue;
QPointF pos = m_points.at(i);
QPointF vec = m_vectors.at(i);
pos += vec;
if (pos.x() < left || pos.x() > right) {
vec.setX(-vec.x());
pos.setX(pos.x() < left ? left : right);
} if (pos.y() < top || pos.y() > bottom) {
vec.setY(-vec.y());
pos.setY(pos.y() < top ? top : bottom);
}
m_points[i] = pos;
m_vectors[i] = vec;
}
update();
}
void PathStrokeRenderer::mousePressEvent(QMouseEvent *e)
{
setDescriptionEnabled(false);
m_activePoint = -1;
qreal distance = -1;
for (int i=0; i<m_points.size(); ++i) {
qreal d = QLineF(e->pos(), m_points.at(i)).length();
if ((distance < 0 && d < 8 * m_pointSize) || d < distance) {
distance = d;
m_activePoint = i;
}
}
if (m_activePoint != -1) {
m_wasAnimated = m_timer.isActive();
setAnimation(false);
mouseMoveEvent(e);
}
}
void PathStrokeRenderer::mouseMoveEvent(QMouseEvent *e)
{
if (m_activePoint >= 0 && m_activePoint < m_points.size()) {
m_points[m_activePoint] = e->pos();
update();
}
}
void PathStrokeRenderer::mouseReleaseEvent(QMouseEvent *)
{
m_activePoint = -1;
setAnimation(m_wasAnimated);
}
void PathStrokeRenderer::timerEvent(QTimerEvent *e)
{
if (e->timerId() == m_timer.timerId()) {
updatePoints();
QApplication::syncX();
} // else if (e->timerId() == m_fpsTimer.timerId()) {
// emit frameRate(m_frameCount);
// m_frameCount = 0;
// }
}
void PathStrokeRenderer::setAnimation(bool animation)
{
m_timer.stop();
// m_fpsTimer.stop();
if (animation) {
m_timer.start(25, this);
// m_fpsTimer.start(1000, this);
// m_frameCount = 0;
}
}
