pathdeform.cpp Example File
demos/deform/pathdeform.cpp
/****************************************************************************
**
** Copyright (C) 2005-2006 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:
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** If you are unsure which license is appropriate for your use, please
** review the following information:
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** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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****************************************************************************/
#include "pathdeform.h"
#include <QApplication>
#include <QtDebug>
#include <QMouseEvent>
#include <QTimerEvent>
#include <QLayout>
#include <QLineEdit>
#include <QPainter>
#include <QSlider>
#include <math.h>
PathDeformWidget::PathDeformWidget(QWidget *parent)
: QWidget(parent)
{
setWindowTitle("Vector Deformation");
m_renderer = new PathDeformRenderer(this);
m_renderer->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
QGroupBox *mainGroup = new QGroupBox(this);
mainGroup->setTitle("Vector Deformation");
QGroupBox *radiusGroup = new QGroupBox(mainGroup);
radiusGroup->setAttribute(Qt::WA_ContentsPropagated);
radiusGroup->setTitle("Lens Radius");
QSlider *radiusSlider = new QSlider(Qt::Horizontal, radiusGroup);
radiusSlider->setRange(50, 150);
radiusSlider->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
QGroupBox *deformGroup = new QGroupBox(mainGroup);
deformGroup->setAttribute(Qt::WA_ContentsPropagated);
deformGroup->setTitle("Deformation");
QSlider *deformSlider = new QSlider(Qt::Horizontal, deformGroup);
deformSlider->setRange(-100, 100);
deformSlider->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
QGroupBox *fontSizeGroup = new QGroupBox(mainGroup);
fontSizeGroup->setAttribute(Qt::WA_ContentsPropagated);
fontSizeGroup->setTitle("Font Size");
QSlider *fontSizeSlider = new QSlider(Qt::Horizontal, fontSizeGroup);
fontSizeSlider->setRange(16, 200);
fontSizeSlider->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
QGroupBox *textGroup = new QGroupBox(mainGroup);
textGroup->setAttribute(Qt::WA_ContentsPropagated);
textGroup->setTitle("Text");
QLineEdit *textInput = new QLineEdit(textGroup);
QPushButton *animateButton = new QPushButton(mainGroup);
animateButton->setText("Animated");
animateButton->setCheckable(true);
QPushButton *showSourceButton = new QPushButton(mainGroup);
showSourceButton->setText("Show Source");
// showSourceButton->setCheckable(true);
QPushButton *whatsThisButton = new QPushButton(mainGroup);
whatsThisButton->setText("What's This?");
whatsThisButton->setCheckable(true);
// Layouts
QHBoxLayout *mainLayout = new QHBoxLayout(this);
mainLayout->addWidget(m_renderer);
mainLayout->addWidget(mainGroup);
mainGroup->setFixedWidth(180);
QVBoxLayout *mainGroupLayout = new QVBoxLayout(mainGroup);
mainGroupLayout->addWidget(radiusGroup);
mainGroupLayout->addWidget(deformGroup);
mainGroupLayout->addWidget(fontSizeGroup);
mainGroupLayout->addWidget(textGroup);
mainGroupLayout->addWidget(animateButton);
mainGroupLayout->addStretch(1);
mainGroupLayout->addWidget(showSourceButton);
mainGroupLayout->addWidget(whatsThisButton);
QVBoxLayout *radiusGroupLayout = new QVBoxLayout(radiusGroup);
radiusGroupLayout->addWidget(radiusSlider);
QVBoxLayout *deformGroupLayout = new QVBoxLayout(deformGroup);
deformGroupLayout->addWidget(deformSlider);
QVBoxLayout *fontSizeGroupLayout = new QVBoxLayout(fontSizeGroup);
fontSizeGroupLayout->addWidget(fontSizeSlider);
QVBoxLayout *textGroupLayout = new QVBoxLayout(textGroup);
textGroupLayout->addWidget(textInput);
connect(textInput, SIGNAL(textChanged(QString)), m_renderer, SLOT(setText(QString)));
connect(radiusSlider, SIGNAL(valueChanged(int)), m_renderer, SLOT(setRadius(int)));
connect(deformSlider, SIGNAL(valueChanged(int)), m_renderer, SLOT(setIntensity(int)));
connect(fontSizeSlider, SIGNAL(valueChanged(int)), m_renderer, SLOT(setFontSize(int)));
connect(animateButton, SIGNAL(clicked(bool)), m_renderer, SLOT(setAnimated(bool)));
connect(whatsThisButton, SIGNAL(clicked(bool)), m_renderer, SLOT(setDescriptionEnabled(bool)));
connect(showSourceButton, SIGNAL(clicked()), m_renderer, SLOT(showSource()));
connect(m_renderer, SIGNAL(descriptionEnabledChanged(bool)),
whatsThisButton, SLOT(setChecked(bool)));
animateButton->animateClick();
deformSlider->setValue(80);
radiusSlider->setValue(100);
fontSizeSlider->setValue(120);
textInput->setText("Qt");
m_renderer->loadSourceFile(":res/pathdeform.cpp");
m_renderer->loadDescription(":res/pathdeform.html");
m_renderer->setDescriptionEnabled(false);
}
static inline QRect circle_bounds(const QPointF ¢er, double radius, double compensation)
{
return QRect(qRound(center.x() - radius - compensation),
qRound(center.y() - radius - compensation),
qRound((radius + compensation) * 2),
qRound((radius + compensation) * 2));
}
const int LENS_EXTENT = 10;
PathDeformRenderer::PathDeformRenderer(QWidget *widget)
: ArthurFrame(widget)
{
m_radius = 100;
m_pos = QPointF(m_radius, m_radius);
m_direction = QPointF(1, 1);
m_fontSize = 24;
m_animated = true;
m_repaintTimer.start(25, this);
m_repaintTracker.start();
m_intensity = 100;
// m_fpsTimer.start(1000, this);
// m_fpsCounter = 0;
generateLensPixmap();
}
void PathDeformRenderer::setText(const QString &text)
{
m_text = text;
QFont f("times new roman,utopia");
f.setStyleStrategy(QFont::ForceOutline);
f.setPointSize(m_fontSize);
f.setStyleHint(QFont::Times);
QFontMetrics fm(f);
m_paths.clear();
m_pathBounds = QRect();
QPointF advance(0, 0);
bool do_quick = true;
for (int i=0; i<text.size(); ++i) {
if (text.at(i).unicode() >= 0x4ff && text.at(i).unicode() <= 0x1e00) {
do_quick = false;
break;
}
}
if (do_quick) {
for (int i=0; i<text.size(); ++i) {
QPainterPath path;
path.addText(advance, f, text.mid(i, 1));
m_pathBounds |= path.boundingRect();
m_paths << path;
advance += QPointF(fm.width(text.mid(i, 1)), 0);
}
} else {
QPainterPath path;
path.addText(advance, f, text);
m_pathBounds |= path.boundingRect();
m_paths << path;
}
for (int i=0; i<m_paths.size(); ++i)
m_paths[i] = m_paths[i] * QMatrix(1, 0, 0, 1, -m_pathBounds.x(), -m_pathBounds.y());
update();
}
void PathDeformRenderer::generateLensPixmap()
{
double rad = m_radius + LENS_EXTENT;
QRect bounds = circle_bounds(QPointF(), rad, 0);
QPainter painter;
if (preferImage()) {
m_lens_image = QImage(bounds.size(), QImage::Format_ARGB32_Premultiplied);
m_lens_image.fill(0);
painter.begin(&m_lens_image);
} else {
m_lens_pixmap = QPixmap(bounds.size());
m_lens_pixmap.fill(QColor(0, 0, 0, 0));
painter.begin(&m_lens_pixmap);
}
QRadialGradient gr(rad, rad, rad, 3 * rad / 5, 3 * rad / 5);
gr.setColorAt(0.0, QColor(255, 255, 255, 191));
gr.setColorAt(0.2, QColor(255, 255, 127, 191));
gr.setColorAt(0.9, QColor(150, 150, 200, 63));
gr.setColorAt(0.95, QColor(0, 0, 0, 127));
gr.setColorAt(1, QColor(0, 0, 0, 0));
painter.setRenderHint(QPainter::Antialiasing);
painter.setBrush(gr);
painter.setPen(Qt::NoPen);
painter.drawEllipse(0, 0, bounds.width(), bounds.height());
}
void PathDeformRenderer::setAnimated(bool animated)
{
m_animated = animated;
if (m_animated) {
// m_fpsTimer.start(1000, this);
// m_fpsCounter = 0;
m_repaintTimer.start(25, this);
m_repaintTracker.start();
} else {
// m_fpsTimer.stop();
m_repaintTimer.stop();
}
}
void PathDeformRenderer::timerEvent(QTimerEvent *e)
{
if (e->timerId() == m_repaintTimer.timerId()) {
if (QLineF(QPointF(0,0), m_direction).length() > 1)
m_direction *= 0.995;
double time = m_repaintTracker.restart();
QRect rectBefore = circle_bounds(m_pos, m_radius, m_fontSize);
double dx = m_direction.x();
double dy = m_direction.y();
if (time > 0) {
dx = dx * time * .1;
dy = dy * time * .1;
}
m_pos += QPointF(dx, dy);
if (m_pos.x() - m_radius < 0) {
m_direction.setX(-m_direction.x());
m_pos.setX(m_radius);
} else if (m_pos.x() + m_radius > width()) {
m_direction.setX(-m_direction.x());
m_pos.setX(width() - m_radius);
}
if (m_pos.y() - m_radius < 0) {
m_direction.setY(-m_direction.y());
m_pos.setY(m_radius);
} else if (m_pos.y() + m_radius > height()) {
m_direction.setY(-m_direction.y());
m_pos.setY(height() - m_radius);
}
QRect rectAfter = circle_bounds(m_pos, m_radius, m_fontSize);
update(QRect(rectBefore | rectAfter));
QApplication::syncX();
}
// else if (e->timerId() == m_fpsTimer.timerId()) {
// printf("fps: %d\n", m_fpsCounter);
// emit frameRate(m_fpsCounter);
// m_fpsCounter = 0;
// }
}
void PathDeformRenderer::mousePressEvent(QMouseEvent *e)
{
setDescriptionEnabled(false);
m_repaintTimer.stop();
m_offset = QPointF();
if (QLineF(m_pos, e->pos()).length() <= m_radius)
m_offset = m_pos - e->pos();
mouseMoveEvent(e);
}
void PathDeformRenderer::mouseReleaseEvent(QMouseEvent *e)
{
if (e->buttons() == Qt::NoButton && m_animated) {
m_repaintTimer.start(10, this);
m_repaintTracker.start();
}
}
void PathDeformRenderer::mouseMoveEvent(QMouseEvent *e)
{
QRect rectBefore = circle_bounds(m_pos, m_radius, m_fontSize);
if (e->type() == QEvent::MouseMove) {
QLineF line(m_pos, e->pos() + m_offset);
line.setLength(line.length() * .1);
QPointF dir(line.dx(), line.dy());
m_direction = (m_direction + dir) / 2;
}
m_pos = e->pos() + m_offset;
QRect rectAfter = circle_bounds(m_pos, m_radius, m_fontSize);
update(rectBefore | rectAfter);
}
QPainterPath PathDeformRenderer::lensDeform(const QPainterPath &source, const QPointF &offset)
{
QPainterPath path;
path.addPath(source);
double flip = m_intensity / 100.0;
for (int i=0; i<path.elementCount(); ++i) {
QPainterPath::Element &e = const_cast<QPainterPath::Element &>(path.elementAt(i));
double x = e.x + offset.x();
double y = e.y + offset.y();
double dx = x - m_pos.x();
double dy = y - m_pos.y();
double len = m_radius - sqrt(dx * dx + dy * dy);
if (len > 0) {
e.x = x + flip * dx * len / m_radius;
e.y = y + flip * dy * len / m_radius;
} else {
e.x = x;
e.y = y;
}
}
return path;
}
void PathDeformRenderer::paint(QPainter *painter)
{
int pad_x = 5;
int pad_y = 5;
int skip_x = qRound(m_pathBounds.width() + pad_x + m_fontSize/2);
int skip_y = qRound(m_pathBounds.height() + pad_y);
painter->setPen(Qt::NoPen);
painter->setBrush(Qt::black);
QRectF clip(painter->clipPath().boundingRect());
int overlap = pad_x / 2;
for (int start_y=0; start_y < height(); start_y += skip_y) {
if (start_y > clip.bottom())
break;
int start_x = -overlap;
for (; start_x < width(); start_x += skip_x) {
if (start_y + skip_y >= clip.top() &&
start_x + skip_x >= clip.left() &&
start_x <= clip.right()) {
for (int i=0; i<m_paths.size(); ++i) {
QPainterPath path = lensDeform(m_paths[i], QPointF(start_x, start_y));
painter->drawPath(path);
}
}
}
overlap = skip_x - (start_x - width());
}
if (preferImage()) {
painter->drawImage(m_pos - QPointF(m_radius + LENS_EXTENT, m_radius + LENS_EXTENT),
m_lens_image);
} else {
painter->drawPixmap(m_pos - QPointF(m_radius + LENS_EXTENT, m_radius + LENS_EXTENT),
m_lens_pixmap);
}
}
void PathDeformRenderer::setRadius(int radius)
{
double max = qMax(m_radius, (double)radius);
m_radius = radius;
generateLensPixmap();
if (!m_animated || m_radius < max)
update(circle_bounds(m_pos, max, m_fontSize));
}
void PathDeformRenderer::setIntensity(int intensity)
{
m_intensity = intensity;
if (!m_animated)
update(circle_bounds(m_pos, m_radius, m_fontSize));
}
