displayshape.cpp Example File
^{tools/qtdemo/displayshape.cpp}

 /****************************************************************************
 **
 ** Copyright (C) 2005-2007 Trolltech ASA. All rights reserved.
 **
 ** This file is part of the example classes 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.
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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 <math.h>
 #include <QtGui>

 #include "displayshape.h"

 DisplayShape::DisplayShape(const QPointF &position, const QSizeF &maxSize)
     : pos(position), maxSize(maxSize), interactive(false)
 {
 }

 bool DisplayShape::animate()
 {
     if (!targetPos.isNull()) {
         QLineF displacement(pos, targetPos);
         QPointF newPosition = displacement.pointAt(0.15);
         if (displacement.length() <= 1.0) {
             pos = targetPos;
             targetPos = QPointF();
         } else {
             pos = newPosition;
         }
         return true;
     }

     return false;
 }

 bool DisplayShape::contains(const QString &key) const
 {
     return meta.contains(key);
 }

 bool DisplayShape::isInteractive() const
 {
     return interactive;
 }

 QVariant DisplayShape::metaData(const QString &key) const
 {
     return meta.value(key);
 }

 void DisplayShape::paint(QPainter *painter) const
 {
     painter->save();
     painter->drawImage(pos, image);
     painter->restore();
 }

 QPointF DisplayShape::position() const
 {
     return pos;
 }

 QRectF DisplayShape::rect() const
 {
     return QRectF(pos, image.size());
 }

 void DisplayShape::removeMetaData(const QString &key)
 {
     meta.remove(key);
 }

 void DisplayShape::setInteractive(bool enable)
 {
     interactive = enable;
 }

 void DisplayShape::setMetaData(const QString &key, const QVariant &value)
 {
     meta[key] = value;
 }

 void DisplayShape::setPosition(const QPointF &position)
 {
     pos = position;
 }

 void DisplayShape::setSize(const QSizeF &size)
 {
     maxSize = size;
 }

 void DisplayShape::setTarget(const QPointF &position)
 {
     targetPos = position;
 }

 QSizeF DisplayShape::size() const
 {
     return maxSize;
 }

 QPointF DisplayShape::target() const
 {
     return targetPos;
 }

 PanelShape::PanelShape(const QPainterPath &path, const QBrush &normal,
                        const QBrush &highlighted, const QPen &pen,
                        const QPointF &position, const QSizeF &maxSize)
     : DisplayShape(position, maxSize), highlightedBrush(highlighted),
       normalBrush(normal), path(path), pen(pen)
 {
     brush = normalBrush;
 }

 bool PanelShape::animate()
 {
     bool updated = false;

     if (!meta.contains("destroy")) {
         if (meta.contains("fade")) {
             QColor penColor = pen.color();
             QColor brushColor = brush.color();
             int penAlpha = penColor.alpha();
             int brushAlpha = brushColor.alpha();
             int fadeMinimum = meta.value("fade minimum").toInt();

             if (penAlpha != fadeMinimum || brushAlpha != fadeMinimum
                 || meta.value("fade").toInt() > 0) {

                 penAlpha = qBound(fadeMinimum,
                                   penAlpha + meta.value("fade").toInt(), 255);
                 brushAlpha = qBound(fadeMinimum,
                                   brushAlpha + meta.value("fade").toInt(), 255);

                 penColor.setAlpha(penAlpha);
                 brushColor.setAlpha(brushAlpha);
                 pen.setColor(penColor);
                 brush.setColor(brushColor);

                 if (penAlpha == 0 && brushAlpha == 0) {
                     meta["destroy"] = true;
                     meta.remove("fade");
                 } else if (penAlpha == 255 && brushAlpha == 255)
                     meta.remove("fade");

                 updated = true;
             }
         } else if (meta.contains("highlight")) {
             qreal scale = meta.value("highlight scale").toDouble();
             QColor color = brush.color();

             if (meta.value("highlight").toBool())
                 scale = qBound(0.0, scale + 0.5, 1.0);
             else
                 scale = qBound(0.0, scale - 0.2, 1.0);

             if (scale == 0.0) {
                 brush = normalBrush;
                 meta.remove("highlight");
                 meta.remove("highlight scale");
                 updated = true;
             } else if (scale != meta["highlight scale"]) {
                 meta["highlight scale"] = scale;

                 if (scale == 1.0)
                     brush = highlightedBrush;
                 else {
                     QColor normal = normalBrush.color();
                     QColor highlighted = highlightedBrush.color();

                     color.setRedF((1.0-scale) * normal.redF()
                                   + scale*highlighted.redF());
                     color.setGreenF((1.0-scale) * normal.greenF()
                                     + scale*highlighted.greenF());
                     color.setBlueF((1.0-scale) * normal.blueF()
                                    + scale*highlighted.blueF());
                     brush.setColor(color);
                 }
                 updated = true;
             }
         }
     }

     return DisplayShape::animate() || updated;
 }

 void PanelShape::paint(QPainter *painter) const
 {
     painter->save();
     painter->setRenderHint(QPainter::Antialiasing);
     painter->setBrush(brush);
     painter->setPen(pen);
     painter->translate(pos);
     painter->drawPath(path);
     painter->restore();
 }

 QRectF PanelShape::rect() const
 {
     return QRectF(pos + path.boundingRect().topLeft(),
                   path.boundingRect().size());
 }

 TitleShape::TitleShape(const QString &text, const QFont &f,
                        const QPen &pen, const QPointF &position,
                        const QSizeF &maxSize, Qt::Alignment alignment)
     : DisplayShape(position, maxSize), font(f), text(text), pen(pen),
       alignment(alignment)
 {
     QFontMetricsF fm(font);
     textRect = fm.boundingRect(QRectF(QPointF(0, 0), maxSize), alignment, text);

     qreal textWidth = qMax(fm.width(text), textRect.width());
     qreal textHeight = qMax(fm.height(), textRect.height());

     qreal scale = qMin(maxSize.width()/textWidth,
                        maxSize.height()/textHeight);

     font.setPointSizeF(font.pointSizeF() * scale);
     fm = QFontMetricsF(font);
     textRect = fm.boundingRect(QRectF(QPointF(0, 0), maxSize), alignment, text);
     baselineStart = QPointF(textRect.left(), textRect.bottom() - fm.descent());
 }

 bool TitleShape::animate()
 {
     bool updated = false;

     if (!meta.contains("destroy")) {
         if (meta.contains("fade")) {
             QColor penColor = pen.color();
             int penAlpha = penColor.alpha();

             penAlpha = qBound(meta.value("fade minimum").toInt(),
                               penAlpha + meta.value("fade").toInt(), 255);

             penColor.setAlpha(penAlpha);
             pen.setColor(penColor);

             if (penAlpha == 0) {
                 meta["destroy"] = true;
                 meta.remove("fade");
             } else if (penAlpha == 255)
                 meta.remove("fade");

             updated = true;
         }
     }

     return DisplayShape::animate() || updated;
 }

 void TitleShape::paint(QPainter *painter) const
 {
     QRectF rect(textRect);
     rect.translate(pos);
     painter->save();
     painter->setRenderHint(QPainter::TextAntialiasing);
     painter->setPen(pen);
     painter->setFont(font);
     painter->drawText(pos + baselineStart, text);
     painter->restore();
 }

 QRectF TitleShape::rect() const
 {
     QRectF rect(textRect);
     return rect.translated(pos);
 }

 ImageShape::ImageShape(const QImage &original, const QPointF &position,
                        const QSizeF &maxSize, int alpha,
                        Qt::Alignment alignment)
     : DisplayShape(position, maxSize), alpha(alpha), alignment(alignment)
 {
     source = original.convertToFormat(QImage::Format_ARGB32_Premultiplied);
     qreal scale = qMin(qMin(maxSize.width()/source.width(),
                             maxSize.height()/source.height()), qreal(1.0));

     source = source.scaled(int(ceil(source.width() * scale)),
                            int(ceil(source.height() * scale)),
                            Qt::KeepAspectRatio,
                            Qt::SmoothTransformation);

     image = QImage(source.size(), QImage::Format_ARGB32_Premultiplied);

     offset = QPointF(0.0, 0.0);

     if (alignment & Qt::AlignHCenter)
         offset.setX((maxSize.width() - image.width())/2);
     else if (alignment & Qt::AlignRight)
         offset.setX(maxSize.width() - image.width());

     if (alignment & Qt::AlignVCenter)
         offset.setY((maxSize.height() - image.height())/2);
     else if (alignment & Qt::AlignBottom)
         offset.setY(maxSize.height() - image.height());

     redraw();
 }

 void ImageShape::redraw()
 {
     image.fill(qRgba(alpha, alpha, alpha, alpha));

     QPainter painter;
     painter.begin(&image);
     painter.setCompositionMode(QPainter::CompositionMode_SourceIn);
     painter.drawImage(0, 0, source);
     painter.end();
 }

 void ImageShape::paint(QPainter *painter) const
 {
     painter->drawImage(pos + offset, image);
 }

 QRectF ImageShape::rect() const
 {
     return QRectF(pos, maxSize);
 }

 bool ImageShape::animate()
 {
     bool updated = false;

     if (!meta.contains("destroy")) {
         if (meta.contains("fade")) {
             alpha = qBound(meta.value("fade minimum").toInt(),
                            alpha + meta.value("fade").toInt(), 255);
             redraw();

             if (alpha == 0) {
                 meta["destroy"] = true;
                 meta.remove("fade");
             } else if (alpha == 255)
                 meta.remove("fade");

             updated = true;
         }
     }

     return DisplayShape::animate() || updated;
 }

 DocumentShape::DocumentShape(const QString &text, const QFont &font,
                              const QPointF &position, const QSizeF &maxSize,
                              int alpha)
     : DisplayShape(position, maxSize), alpha(alpha)
 {
     textDocument.setHtml(text);
     textDocument.setDefaultFont(font);
     textDocument.setPageSize(maxSize);
     QSizeF documentSize = textDocument.documentLayout()->documentSize();
     setSize(QSizeF(maxSize.width(),
                       qMin(maxSize.height(), documentSize.height())));

     source = QImage(int(ceil(documentSize.width())),
                     int(ceil(documentSize.height())),
                     QImage::Format_ARGB32_Premultiplied);
     source.fill(qRgba(255, 255, 255, 255));

     QAbstractTextDocumentLayout::PaintContext context;
     textDocument.documentLayout()->setPaintDevice(&source);

     QPainter painter;
     painter.begin(&source);
     painter.setRenderHint(QPainter::TextAntialiasing);
     painter.setRenderHint(QPainter::Antialiasing);
     textDocument.documentLayout()->draw(&painter, context);
     painter.end();

     source = source.scaled(int(ceil(maxSize.width())),
                            int(ceil(maxSize.height())),
                            Qt::KeepAspectRatio,
                            Qt::SmoothTransformation);

     image = QImage(source.size(), source.format());
     redraw();
 }

 DocumentShape::~DocumentShape()
 {
 }

 bool DocumentShape::animate()
 {
     bool updated = false;

     if (!meta.contains("destroy")) {
         if (meta.contains("fade")) {
             alpha = qBound(meta.value("fade minimum").toInt(),
                            alpha + meta.value("fade").toInt(), 255);
             redraw();

             if (alpha == 0) {
                 meta["destroy"] = true;
                 meta.remove("fade");
             } else if (alpha == 255)
                 meta.remove("fade");

             updated = true;
         }
     }

     return DisplayShape::animate() || updated;
 }

 void DocumentShape::redraw()
 {
     image.fill(qRgba(alpha, alpha, alpha, alpha));

     QPainter painter;
     painter.begin(&image);
     painter.setCompositionMode(QPainter::CompositionMode_SourceIn);
     painter.drawImage(0, 0, source);
     painter.end();
 }

 void DocumentShape::paint(QPainter *painter) const
 {
     painter->drawImage(pos, image);
 }

 QRectF DocumentShape::rect() const
 {
     return QRectF(pos, maxSize);
 }