qt5base-lts/examples/painting/gradients/gradients.cpp
Jason McDonald 5635823e17 Remove "All rights reserved" line from license headers.
As in the past, to avoid rewriting various autotests that contain
line-number information, an extra blank line has been inserted at the
end of the license text to ensure that this commit does not change the
total number of lines in the license header.

Change-Id: I311e001373776812699d6efc045b5f742890c689
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>
2012-01-30 03:54:59 +01:00

517 lines
18 KiB
C++

/****************************************************************************
**
** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
** Contact: http://www.qt-project.org/
**
** This file is part of the demonstration applications of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** GNU Lesser General Public License Usage
** 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.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU General
** Public License version 3.0 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 the GNU General
** Public License version 3.0 requirements will be met:
** http://www.gnu.org/copyleft/gpl.html.
**
** Other Usage
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**
**
**
**
** $QT_END_LICENSE$
**
****************************************************************************/
#include "gradients.h"
#include "hoverpoints.h"
ShadeWidget::ShadeWidget(ShadeType type, QWidget *parent)
: QWidget(parent), m_shade_type(type), m_alpha_gradient(QLinearGradient(0, 0, 0, 0))
{
// Checkers background
if (m_shade_type == ARGBShade) {
QPixmap pm(20, 20);
QPainter pmp(&pm);
pmp.fillRect(0, 0, 10, 10, Qt::lightGray);
pmp.fillRect(10, 10, 10, 10, Qt::lightGray);
pmp.fillRect(0, 10, 10, 10, Qt::darkGray);
pmp.fillRect(10, 0, 10, 10, Qt::darkGray);
pmp.end();
QPalette pal = palette();
pal.setBrush(backgroundRole(), QBrush(pm));
setAutoFillBackground(true);
setPalette(pal);
} else {
setAttribute(Qt::WA_NoBackground);
}
QPolygonF points;
points << QPointF(0, sizeHint().height())
<< QPointF(sizeHint().width(), 0);
m_hoverPoints = new HoverPoints(this, HoverPoints::CircleShape);
// m_hoverPoints->setConnectionType(HoverPoints::LineConnection);
m_hoverPoints->setPoints(points);
m_hoverPoints->setPointLock(0, HoverPoints::LockToLeft);
m_hoverPoints->setPointLock(1, HoverPoints::LockToRight);
m_hoverPoints->setSortType(HoverPoints::XSort);
setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
connect(m_hoverPoints, SIGNAL(pointsChanged(QPolygonF)), this, SIGNAL(colorsChanged()));
}
QPolygonF ShadeWidget::points() const
{
return m_hoverPoints->points();
}
uint ShadeWidget::colorAt(int x)
{
generateShade();
QPolygonF pts = m_hoverPoints->points();
for (int i=1; i < pts.size(); ++i) {
if (pts.at(i-1).x() <= x && pts.at(i).x() >= x) {
QLineF l(pts.at(i-1), pts.at(i));
l.setLength(l.length() * ((x - l.x1()) / l.dx()));
return m_shade.pixel(qRound(qMin(l.x2(), (qreal(m_shade.width() - 1)))),
qRound(qMin(l.y2(), qreal(m_shade.height() - 1))));
}
}
return 0;
}
void ShadeWidget::setGradientStops(const QGradientStops &stops)
{
if (m_shade_type == ARGBShade) {
m_alpha_gradient = QLinearGradient(0, 0, width(), 0);
for (int i=0; i<stops.size(); ++i) {
QColor c = stops.at(i).second;
m_alpha_gradient.setColorAt(stops.at(i).first, QColor(c.red(), c.green(), c.blue()));
}
m_shade = QImage();
generateShade();
update();
}
}
void ShadeWidget::paintEvent(QPaintEvent *)
{
generateShade();
QPainter p(this);
p.drawImage(0, 0, m_shade);
p.setPen(QColor(146, 146, 146));
p.drawRect(0, 0, width() - 1, height() - 1);
}
void ShadeWidget::generateShade()
{
if (m_shade.isNull() || m_shade.size() != size()) {
if (m_shade_type == ARGBShade) {
m_shade = QImage(size(), QImage::Format_ARGB32_Premultiplied);
m_shade.fill(0);
QPainter p(&m_shade);
p.fillRect(rect(), m_alpha_gradient);
p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
QLinearGradient fade(0, 0, 0, height());
fade.setColorAt(0, QColor(0, 0, 0, 255));
fade.setColorAt(1, QColor(0, 0, 0, 0));
p.fillRect(rect(), fade);
} else {
m_shade = QImage(size(), QImage::Format_RGB32);
QLinearGradient shade(0, 0, 0, height());
shade.setColorAt(1, Qt::black);
if (m_shade_type == RedShade)
shade.setColorAt(0, Qt::red);
else if (m_shade_type == GreenShade)
shade.setColorAt(0, Qt::green);
else
shade.setColorAt(0, Qt::blue);
QPainter p(&m_shade);
p.fillRect(rect(), shade);
}
}
}
GradientEditor::GradientEditor(QWidget *parent)
: QWidget(parent)
{
QVBoxLayout *vbox = new QVBoxLayout(this);
vbox->setSpacing(1);
vbox->setMargin(1);
m_red_shade = new ShadeWidget(ShadeWidget::RedShade, this);
m_green_shade = new ShadeWidget(ShadeWidget::GreenShade, this);
m_blue_shade = new ShadeWidget(ShadeWidget::BlueShade, this);
m_alpha_shade = new ShadeWidget(ShadeWidget::ARGBShade, this);
vbox->addWidget(m_red_shade);
vbox->addWidget(m_green_shade);
vbox->addWidget(m_blue_shade);
vbox->addWidget(m_alpha_shade);
connect(m_red_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
connect(m_green_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
connect(m_blue_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
connect(m_alpha_shade, SIGNAL(colorsChanged()), this, SLOT(pointsUpdated()));
}
inline static bool x_less_than(const QPointF &p1, const QPointF &p2)
{
return p1.x() < p2.x();
}
void GradientEditor::pointsUpdated()
{
qreal w = m_alpha_shade->width();
QGradientStops stops;
QPolygonF points;
points += m_red_shade->points();
points += m_green_shade->points();
points += m_blue_shade->points();
points += m_alpha_shade->points();
qSort(points.begin(), points.end(), x_less_than);
for (int i=0; i<points.size(); ++i) {
qreal x = int(points.at(i).x());
if (i+1 < points.size() && x == points.at(i+1).x())
continue;
QColor color((0x00ff0000 & m_red_shade->colorAt(int(x))) >> 16,
(0x0000ff00 & m_green_shade->colorAt(int(x))) >> 8,
(0x000000ff & m_blue_shade->colorAt(int(x))),
(0xff000000 & m_alpha_shade->colorAt(int(x))) >> 24);
if (x / w > 1)
return;
stops << QGradientStop(x / w, color);
}
m_alpha_shade->setGradientStops(stops);
emit gradientStopsChanged(stops);
}
static void set_shade_points(const QPolygonF &points, ShadeWidget *shade)
{
shade->hoverPoints()->setPoints(points);
shade->hoverPoints()->setPointLock(0, HoverPoints::LockToLeft);
shade->hoverPoints()->setPointLock(points.size() - 1, HoverPoints::LockToRight);
shade->update();
}
void GradientEditor::setGradientStops(const QGradientStops &stops)
{
QPolygonF pts_red, pts_green, pts_blue, pts_alpha;
qreal h_red = m_red_shade->height();
qreal h_green = m_green_shade->height();
qreal h_blue = m_blue_shade->height();
qreal h_alpha = m_alpha_shade->height();
for (int i=0; i<stops.size(); ++i) {
qreal pos = stops.at(i).first;
QRgb color = stops.at(i).second.rgba();
pts_red << QPointF(pos * m_red_shade->width(), h_red - qRed(color) * h_red / 255);
pts_green << QPointF(pos * m_green_shade->width(), h_green - qGreen(color) * h_green / 255);
pts_blue << QPointF(pos * m_blue_shade->width(), h_blue - qBlue(color) * h_blue / 255);
pts_alpha << QPointF(pos * m_alpha_shade->width(), h_alpha - qAlpha(color) * h_alpha / 255);
}
set_shade_points(pts_red, m_red_shade);
set_shade_points(pts_green, m_green_shade);
set_shade_points(pts_blue, m_blue_shade);
set_shade_points(pts_alpha, m_alpha_shade);
}
GradientWidget::GradientWidget(QWidget *parent)
: QWidget(parent)
{
setWindowTitle(tr("Gradients"));
m_renderer = new GradientRenderer(this);
QGroupBox *mainGroup = new QGroupBox(this);
mainGroup->setTitle(tr("Gradients"));
QGroupBox *editorGroup = new QGroupBox(mainGroup);
editorGroup->setTitle(tr("Color Editor"));
m_editor = new GradientEditor(editorGroup);
QGroupBox *typeGroup = new QGroupBox(mainGroup);
typeGroup->setTitle(tr("Gradient Type"));
m_linearButton = new QRadioButton(tr("Linear Gradient"), typeGroup);
m_radialButton = new QRadioButton(tr("Radial Gradient"), typeGroup);
m_conicalButton = new QRadioButton(tr("Conical Gradient"), typeGroup);
QGroupBox *spreadGroup = new QGroupBox(mainGroup);
spreadGroup->setTitle(tr("Spread Method"));
m_padSpreadButton = new QRadioButton(tr("Pad Spread"), spreadGroup);
m_reflectSpreadButton = new QRadioButton(tr("Reflect Spread"), spreadGroup);
m_repeatSpreadButton = new QRadioButton(tr("Repeat Spread"), spreadGroup);
QGroupBox *defaultsGroup = new QGroupBox(mainGroup);
defaultsGroup->setTitle(tr("Defaults"));
QPushButton *default1Button = new QPushButton(tr("1"), defaultsGroup);
QPushButton *default2Button = new QPushButton(tr("2"), defaultsGroup);
QPushButton *default3Button = new QPushButton(tr("3"), defaultsGroup);
QPushButton *default4Button = new QPushButton(tr("Reset"), editorGroup);
QPushButton *showSourceButton = new QPushButton(mainGroup);
showSourceButton->setText(tr("Show Source"));
#ifdef QT_OPENGL_SUPPORT
QPushButton *enableOpenGLButton = new QPushButton(mainGroup);
enableOpenGLButton->setText(tr("Use OpenGL"));
enableOpenGLButton->setCheckable(true);
enableOpenGLButton->setChecked(m_renderer->usesOpenGL());
if (!QGLFormat::hasOpenGL())
enableOpenGLButton->hide();
#endif
QPushButton *whatsThisButton = new QPushButton(mainGroup);
whatsThisButton->setText(tr("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(editorGroup);
mainGroupLayout->addWidget(typeGroup);
mainGroupLayout->addWidget(spreadGroup);
mainGroupLayout->addWidget(defaultsGroup);
mainGroupLayout->addStretch(1);
mainGroupLayout->addWidget(showSourceButton);
#ifdef QT_OPENGL_SUPPORT
mainGroupLayout->addWidget(enableOpenGLButton);
#endif
mainGroupLayout->addWidget(whatsThisButton);
QVBoxLayout *editorGroupLayout = new QVBoxLayout(editorGroup);
editorGroupLayout->addWidget(m_editor);
QVBoxLayout *typeGroupLayout = new QVBoxLayout(typeGroup);
typeGroupLayout->addWidget(m_linearButton);
typeGroupLayout->addWidget(m_radialButton);
typeGroupLayout->addWidget(m_conicalButton);
QVBoxLayout *spreadGroupLayout = new QVBoxLayout(spreadGroup);
spreadGroupLayout->addWidget(m_padSpreadButton);
spreadGroupLayout->addWidget(m_repeatSpreadButton);
spreadGroupLayout->addWidget(m_reflectSpreadButton);
QHBoxLayout *defaultsGroupLayout = new QHBoxLayout(defaultsGroup);
defaultsGroupLayout->addWidget(default1Button);
defaultsGroupLayout->addWidget(default2Button);
defaultsGroupLayout->addWidget(default3Button);
editorGroupLayout->addWidget(default4Button);
connect(m_editor, SIGNAL(gradientStopsChanged(QGradientStops)),
m_renderer, SLOT(setGradientStops(QGradientStops)));
connect(m_linearButton, SIGNAL(clicked()), m_renderer, SLOT(setLinearGradient()));
connect(m_radialButton, SIGNAL(clicked()), m_renderer, SLOT(setRadialGradient()));
connect(m_conicalButton, SIGNAL(clicked()), m_renderer, SLOT(setConicalGradient()));
connect(m_padSpreadButton, SIGNAL(clicked()), m_renderer, SLOT(setPadSpread()));
connect(m_reflectSpreadButton, SIGNAL(clicked()), m_renderer, SLOT(setReflectSpread()));
connect(m_repeatSpreadButton, SIGNAL(clicked()), m_renderer, SLOT(setRepeatSpread()));
connect(default1Button, SIGNAL(clicked()), this, SLOT(setDefault1()));
connect(default2Button, SIGNAL(clicked()), this, SLOT(setDefault2()));
connect(default3Button, SIGNAL(clicked()), this, SLOT(setDefault3()));
connect(default4Button, SIGNAL(clicked()), this, SLOT(setDefault4()));
connect(showSourceButton, SIGNAL(clicked()), m_renderer, SLOT(showSource()));
#ifdef QT_OPENGL_SUPPORT
connect(enableOpenGLButton, SIGNAL(clicked(bool)), m_renderer, SLOT(enableOpenGL(bool)));
#endif
connect(whatsThisButton, SIGNAL(clicked(bool)), m_renderer, SLOT(setDescriptionEnabled(bool)));
connect(whatsThisButton, SIGNAL(clicked(bool)),
m_renderer->hoverPoints(), SLOT(setDisabled(bool)));
connect(m_renderer, SIGNAL(descriptionEnabledChanged(bool)),
whatsThisButton, SLOT(setChecked(bool)));
connect(m_renderer, SIGNAL(descriptionEnabledChanged(bool)),
m_renderer->hoverPoints(), SLOT(setDisabled(bool)));
m_renderer->loadSourceFile(":res/gradients/gradients.cpp");
m_renderer->loadDescription(":res/gradients/gradients.html");
QTimer::singleShot(50, this, SLOT(setDefault1()));
}
void GradientWidget::setDefault(int config)
{
QGradientStops stops;
QPolygonF points;
switch (config) {
case 1:
stops << QGradientStop(0.00, QColor::fromRgba(0));
stops << QGradientStop(0.04, QColor::fromRgba(0xff131360));
stops << QGradientStop(0.08, QColor::fromRgba(0xff202ccc));
stops << QGradientStop(0.42, QColor::fromRgba(0xff93d3f9));
stops << QGradientStop(0.51, QColor::fromRgba(0xffb3e6ff));
stops << QGradientStop(0.73, QColor::fromRgba(0xffffffec));
stops << QGradientStop(0.92, QColor::fromRgba(0xff5353d9));
stops << QGradientStop(0.96, QColor::fromRgba(0xff262666));
stops << QGradientStop(1.00, QColor::fromRgba(0));
m_linearButton->animateClick();
m_repeatSpreadButton->animateClick();
break;
case 2:
stops << QGradientStop(0.00, QColor::fromRgba(0xffffffff));
stops << QGradientStop(0.11, QColor::fromRgba(0xfff9ffa0));
stops << QGradientStop(0.13, QColor::fromRgba(0xfff9ff99));
stops << QGradientStop(0.14, QColor::fromRgba(0xfff3ff86));
stops << QGradientStop(0.49, QColor::fromRgba(0xff93b353));
stops << QGradientStop(0.87, QColor::fromRgba(0xff264619));
stops << QGradientStop(0.96, QColor::fromRgba(0xff0c1306));
stops << QGradientStop(1.00, QColor::fromRgba(0));
m_radialButton->animateClick();
m_padSpreadButton->animateClick();
break;
case 3:
stops << QGradientStop(0.00, QColor::fromRgba(0));
stops << QGradientStop(0.10, QColor::fromRgba(0xffe0cc73));
stops << QGradientStop(0.17, QColor::fromRgba(0xffc6a006));
stops << QGradientStop(0.46, QColor::fromRgba(0xff600659));
stops << QGradientStop(0.72, QColor::fromRgba(0xff0680ac));
stops << QGradientStop(0.92, QColor::fromRgba(0xffb9d9e6));
stops << QGradientStop(1.00, QColor::fromRgba(0));
m_conicalButton->animateClick();
m_padSpreadButton->animateClick();
break;
case 4:
stops << QGradientStop(0.00, QColor::fromRgba(0xff000000));
stops << QGradientStop(1.00, QColor::fromRgba(0xffffffff));
break;
default:
qWarning("bad default: %d\n", config);
break;
}
QPolygonF pts;
int h_off = m_renderer->width() / 10;
int v_off = m_renderer->height() / 8;
pts << QPointF(m_renderer->width() / 2, m_renderer->height() / 2)
<< QPointF(m_renderer->width() / 2 - h_off, m_renderer->height() / 2 - v_off);
m_editor->setGradientStops(stops);
m_renderer->hoverPoints()->setPoints(pts);
m_renderer->setGradientStops(stops);
}
GradientRenderer::GradientRenderer(QWidget *parent)
: ArthurFrame(parent)
{
m_hoverPoints = new HoverPoints(this, HoverPoints::CircleShape);
m_hoverPoints->setPointSize(QSize(20, 20));
m_hoverPoints->setConnectionType(HoverPoints::NoConnection);
m_hoverPoints->setEditable(false);
QVector<QPointF> points;
points << QPointF(100, 100) << QPointF(200, 200);
m_hoverPoints->setPoints(points);
m_spread = QGradient::PadSpread;
m_gradientType = Qt::LinearGradientPattern;
}
void GradientRenderer::setGradientStops(const QGradientStops &stops)
{
m_stops = stops;
update();
}
void GradientRenderer::mousePressEvent(QMouseEvent *)
{
setDescriptionEnabled(false);
}
void GradientRenderer::paint(QPainter *p)
{
QPolygonF pts = m_hoverPoints->points();
QGradient g;
if (m_gradientType == Qt::LinearGradientPattern) {
g = QLinearGradient(pts.at(0), pts.at(1));
} else if (m_gradientType == Qt::RadialGradientPattern) {
g = QRadialGradient(pts.at(0), qMin(width(), height()) / 3.0, pts.at(1));
} else {
QLineF l(pts.at(0), pts.at(1));
qreal angle = l.angle(QLineF(0, 0, 1, 0));
if (l.dy() > 0)
angle = 360 - angle;
g = QConicalGradient(pts.at(0), angle);
}
for (int i=0; i<m_stops.size(); ++i)
g.setColorAt(m_stops.at(i).first, m_stops.at(i).second);
g.setSpread(m_spread);
p->setBrush(g);
p->setPen(Qt::NoPen);
p->drawRect(rect());
}