composition.cpp Example File
demos/composition/composition.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:
** http://www.trolltech.com/products/qt/opensource.html
**
** If you are unsure which license is appropriate for your use, please
** review the following information:
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** sales department at sales@trolltech.com.
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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.
**
****************************************************************************/
#include "composition.h"
#include <QBoxLayout>
#include <QRadioButton>
#include <QTimer>
#include <QDateTime>
#include <QSlider>
#include <QMouseEvent>
#include <math.h>
CompositionWidget::CompositionWidget(QWidget *parent)
: QWidget(parent)
{
CompositionRenderer *view = new CompositionRenderer(this);
QGroupBox *mainGroup = new QGroupBox(parent);
mainGroup->setAttribute(Qt::WA_ContentsPropagated);
mainGroup->setTitle("Composition Modes");
QGroupBox *modesGroup = new QGroupBox(mainGroup);
modesGroup->setAttribute(Qt::WA_ContentsPropagated);
modesGroup->setTitle("Mode");
rbClear = new QRadioButton("Clear", modesGroup);
connect(rbClear, SIGNAL(clicked()), view, SLOT(setClearMode()));
rbSource = new QRadioButton("Source", modesGroup);
connect(rbSource, SIGNAL(clicked()), view, SLOT(setSourceMode()));
rbDest = new QRadioButton("Destination", modesGroup);
connect(rbDest, SIGNAL(clicked()), view, SLOT(setDestMode()));
rbSourceOver = new QRadioButton("Source Over", modesGroup);
connect(rbSourceOver, SIGNAL(clicked()), view, SLOT(setSourceOverMode()));
rbDestOver = new QRadioButton("Destination Over", modesGroup);
connect(rbDestOver, SIGNAL(clicked()), view, SLOT(setDestOverMode()));
rbSourceIn = new QRadioButton("Source In", modesGroup);
connect(rbSourceIn, SIGNAL(clicked()), view, SLOT(setSourceInMode()));
rbDestIn = new QRadioButton("Dest In", modesGroup);
connect(rbDestIn, SIGNAL(clicked()), view, SLOT(setDestInMode()));
rbSourceOut = new QRadioButton("Source Out", modesGroup);
connect(rbSourceOut, SIGNAL(clicked()), view, SLOT(setSourceOutMode()));
rbDestOut = new QRadioButton("Dest Out", modesGroup);
connect(rbDestOut, SIGNAL(clicked()), view, SLOT(setDestOutMode()));
rbSourceAtop = new QRadioButton("Source Atop", modesGroup);
connect(rbSourceAtop, SIGNAL(clicked()), view, SLOT(setSourceAtopMode()));
rbDestAtop = new QRadioButton("Dest Atop", modesGroup);
connect(rbDestAtop, SIGNAL(clicked()), view, SLOT(setDestAtopMode()));
rbXor = new QRadioButton("Xor", modesGroup);
connect(rbXor, SIGNAL(clicked()), view, SLOT(setXorMode()));
QGroupBox *circleColorGroup = new QGroupBox(mainGroup);
circleColorGroup->setAttribute(Qt::WA_ContentsPropagated);
circleColorGroup->setTitle("Circle color");
QSlider *circleColorSlider = new QSlider(Qt::Horizontal, circleColorGroup);
circleColorSlider->setRange(0, 359);
circleColorSlider->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
connect(circleColorSlider, SIGNAL(valueChanged(int)), view, SLOT(setCircleColor(int)));
QGroupBox *circleAlphaGroup = new QGroupBox(mainGroup);
circleAlphaGroup->setAttribute(Qt::WA_ContentsPropagated);
circleAlphaGroup->setTitle("Circle alpha");
QSlider *circleAlphaSlider = new QSlider(Qt::Horizontal, circleAlphaGroup);
circleAlphaSlider->setRange(0, 255);
circleAlphaSlider->setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Fixed);
connect(circleAlphaSlider, SIGNAL(valueChanged(int)), view, SLOT(setCircleAlpha(int)));
QPushButton *showSourceButton = new QPushButton(mainGroup);
showSourceButton->setText("Show Source");
QPushButton *whatsThisButton = new QPushButton(mainGroup);
whatsThisButton->setText("What's This?");
whatsThisButton->setCheckable(true);
QPushButton *animateButton = new QPushButton(mainGroup);
animateButton->setText("Animated");
animateButton->setCheckable(true);
animateButton->setChecked(true);
QHBoxLayout *viewLayout = new QHBoxLayout(this);
viewLayout->addWidget(view);
viewLayout->addWidget(mainGroup);
QVBoxLayout *mainGroupLayout = new QVBoxLayout(mainGroup);
mainGroupLayout->addWidget(circleColorGroup);
mainGroupLayout->addWidget(circleAlphaGroup);
mainGroupLayout->addWidget(modesGroup);
mainGroupLayout->addStretch();
mainGroupLayout->addWidget(animateButton);
mainGroupLayout->addWidget(whatsThisButton);
mainGroupLayout->addWidget(showSourceButton);
QVBoxLayout *modesLayout = new QVBoxLayout(modesGroup);
modesLayout->addWidget(rbClear);
modesLayout->addWidget(rbSource);
modesLayout->addWidget(rbDest);
modesLayout->addWidget(rbSourceOver);
modesLayout->addWidget(rbDestOver);
modesLayout->addWidget(rbSourceIn);
modesLayout->addWidget(rbDestIn);
modesLayout->addWidget(rbSourceOut);
modesLayout->addWidget(rbDestOut);
modesLayout->addWidget(rbSourceAtop);
modesLayout->addWidget(rbDestAtop);
modesLayout->addWidget(rbXor);
QVBoxLayout *circleColorLayout = new QVBoxLayout(circleColorGroup);
circleColorLayout->addWidget(circleColorSlider);
QVBoxLayout *circleAlphaLayout = new QVBoxLayout(circleAlphaGroup);
circleAlphaLayout->addWidget(circleAlphaSlider);
view->loadDescription(":res/composition.html");
view->loadSourceFile(":res/composition.cpp");
connect(whatsThisButton, SIGNAL(clicked(bool)), view, SLOT(setDescriptionEnabled(bool)));
connect(view, SIGNAL(descriptionEnabledChanged(bool)), whatsThisButton, SLOT(setChecked(bool)));
connect(showSourceButton, SIGNAL(clicked()), view, SLOT(showSource()));
connect(animateButton, SIGNAL(toggled(bool)), view, SLOT(setAnimationEnabled(bool)));
circleColorSlider->setValue(270);
circleAlphaSlider->setValue(200);
rbSourceOut->animateClick();
setWindowTitle(tr("Composition Modes"));
}
void CompositionWidget::nextMode()
{
/*
if (!m_animation_enabled)
return;
if (rbClear->isChecked()) rbSource->animateClick();
if (rbSource->isChecked()) rbDest->animateClick();
if (rbDest->isChecked()) rbSourceOver->animateClick();
if (rbSourceOver->isChecked()) rbDestOver->animateClick();
if (rbDestOver->isChecked()) rbSourceIn->animateClick();
if (rbSourceIn->isChecked()) rbDestIn->animateClick();
if (rbDestIn->isChecked()) rbSourceOut->animateClick();
if (rbSourceOut->isChecked()) rbDestOut->animateClick();
if (rbDestOut->isChecked()) rbSourceAtop->animateClick();
if (rbSourceAtop->isChecked()) rbDestAtop->animateClick();
if (rbDestAtop->isChecked()) rbXor->animateClick();
if (rbXor->isChecked()) rbClear->animateClick();
*/
}
CompositionRenderer::CompositionRenderer(QWidget *parent)
: ArthurFrame(parent)
{
m_animation_enabled = true;
m_image = QImage(":res/flower_2.png");
m_circle_alpha = 127;
m_circle_hue = 255;
m_current_object = NoObject;
m_composition_mode = QPainter::CompositionMode_SourceOut;
m_circle_pos = QPoint(200, 100);
setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);
}
QRectF rectangle_around(const QPointF &p, const QSizeF &size = QSize(250, 200))
{
QRectF rect(p, size);
rect.translate(-size.width()/2, -size.height()/2);
return rect;
}
void CompositionRenderer::updateCirclePos()
{
if (m_current_object != NoObject)
return;
QDateTime dt = QDateTime::currentDateTime();
qreal t = (dt.toTime_t() * 1000 + dt.time().msec()) / 1000.0;
qreal x = width() / 2.0 + (cos(t) + sin(-t*2)) * width() / 2.0;
qreal y = height() / 2.0 + (sin(t) + cos(t * 3)) * height() / 2.0;
m_circle_pos = QLineF(m_circle_pos, QPointF(x, y)).pointAt(0.01);
}
void CompositionRenderer::paint(QPainter *painter)
{
if (m_animation_enabled)
updateCirclePos();
if (m_buffer.size() != size()) {
m_buffer = QImage(size(), QImage::Format_ARGB32_Premultiplied);
m_base_buffer = QImage(size(), QImage::Format_ARGB32_Premultiplied);
m_base_buffer.fill(0);
QPainter p(&m_base_buffer);
p.setPen(Qt::NoPen);
QLinearGradient rect_gradient(0, 0, 0, height());
rect_gradient.setColorAt(0, Qt::red);
rect_gradient.setColorAt(.17, Qt::yellow);
rect_gradient.setColorAt(.33, Qt::green);
rect_gradient.setColorAt(.50, Qt::cyan);
rect_gradient.setColorAt(.66, Qt::blue);
rect_gradient.setColorAt(.81, Qt::magenta);
rect_gradient.setColorAt(1, Qt::red);
p.setBrush(rect_gradient);
p.drawRect(width() / 2, 0, width() / 2, height());
QLinearGradient alpha_gradient(0, 0, width(), 0);
alpha_gradient.setColorAt(0, Qt::white);
alpha_gradient.setColorAt(0.2, Qt::white);
alpha_gradient.setColorAt(0.5, Qt::transparent);
alpha_gradient.setColorAt(0.8, Qt::white);
alpha_gradient.setColorAt(1, Qt::white);
p.setCompositionMode(QPainter::CompositionMode_DestinationIn);
p.setBrush(alpha_gradient);
p.drawRect(0, 0, width(), height());
p.setCompositionMode(QPainter::CompositionMode_DestinationOver);
p.setPen(Qt::NoPen);
p.setRenderHint(QPainter::SmoothPixmapTransform);
p.drawImage(rect(), m_image);
}
memcpy(m_buffer.bits(), m_base_buffer.bits(), m_buffer.numBytes());
{
QPainter p(&m_buffer);
p.setPen(Qt::NoPen);
p.setRenderHint(QPainter::Antialiasing);
p.setCompositionMode(m_composition_mode);
QRectF circle_rect = rectangle_around(m_circle_pos);
QColor color = QColor::fromHsvF(m_circle_hue / 360.0, 1, 1, m_circle_alpha / 255.0);
QLinearGradient circle_gradient(circle_rect.topLeft(), circle_rect.bottomRight());
circle_gradient.setColorAt(0, color.light());
circle_gradient.setColorAt(0.5, color);
circle_gradient.setColorAt(1, color.dark());
p.setBrush(circle_gradient);
p.drawEllipse(circle_rect);
}
painter->drawImage(0, 0, m_buffer);
if (m_animation_enabled)
update();
}
void CompositionRenderer::mousePressEvent(QMouseEvent *e)
{
setDescriptionEnabled(false);
QRectF circle = rectangle_around(m_circle_pos);
if (circle.contains(e->pos())) {
m_current_object = Circle;
m_offset = circle.center() - e->pos();
} else {
m_current_object = NoObject;
}
}
void CompositionRenderer::mouseMoveEvent(QMouseEvent *e)
{
if (m_current_object == Circle) setCirclePos(e->pos() + m_offset);
}
void CompositionRenderer::mouseReleaseEvent(QMouseEvent *)
{
m_current_object = NoObject;
}
