File indexing completed on 2024-05-12 04:20:37

 /*
  * SPDX-FileCopyrightText: 2001-2015 Klaralvdalens Datakonsult AB. All rights reserved.
  *
  * This file is part of the KD Chart library.
  *
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
 
 #include "KChartTextLabelCache.h"
 
 #include <cmath>
 
 #include <QtDebug>
 #include <QImage>
 #include <QPainter>
 #include <QApplication>
 
 #ifndef NDEBUG
 int HitCount = 0;
 int MissCount = 0;
 #define INC_HIT_COUNT { ++HitCount; }
 #define INC_MISS_COUNT  { ++MissCount; }
 #define DUMP_CACHE_STATS \
     if ( HitCount != 0 && MissCount != 0 ) { \
         int total = HitCount + MissCount; \
         qreal hitQuote = ( 1.0 * HitCount ) / total; \
         qDebug() << "PrerenderedLabel dtor: hits/misses/total:" \
         << HitCount << "/" << MissCount << "/" << total \
                  << "(" << 100 * hitQuote << "% hits)"; \
     }
 #else
 #define INC_HIT_COUNT
 #define INC_MISS_COUNT
 #define DUMP_CACHE_STATS
 #endif
 
 PrerenderedElement::PrerenderedElement()
     : m_referencePoint( KChartEnums::PositionNorthWest )
 {
 }
 
 void PrerenderedElement::setPosition( const QPointF& position )
 {   // this does not invalidate the element
     m_position = position;
 }
 
 const QPointF& PrerenderedElement::position() const
 {
     return m_position;
 }
 
 void PrerenderedElement::setReferencePoint( KChartEnums::PositionValue point )
 {   // this does not invalidate the element
     m_referencePoint = point;
 }
 
 KChartEnums::PositionValue PrerenderedElement::referencePoint() const
 {
     return m_referencePoint;
 }
 
 PrerenderedLabel::PrerenderedLabel()
     : PrerenderedElement()
     , m_dirty( true )
     , m_font( qApp->font() )
     , m_brush( Qt::black )
     , m_pen( Qt::black ) // do not use anything invisible
     , m_angle( 0.0 )
 {
 }
 
 PrerenderedLabel::~PrerenderedLabel()
 {
     DUMP_CACHE_STATS;
 }
 
 void PrerenderedLabel::invalidate() const
 {
     m_dirty = true;
 }
 
 void PrerenderedLabel::setFont( const QFont& font )
 {
     m_font = font;
     invalidate();
 }
 
 const QFont& PrerenderedLabel::font() const
 {
     return m_font;
 }
 
 void PrerenderedLabel::setText( const QString& text )
 {
     m_text = text;
     invalidate();
 }
 
 const QString& PrerenderedLabel::text() const
 {
     return m_text;
 }
 
 void PrerenderedLabel::setBrush( const QBrush& brush )
 {
     m_brush = brush;
     invalidate();
 }
 
 const QBrush& PrerenderedLabel::brush() const
 {
     return m_brush;
 }
 
 void PrerenderedLabel::setAngle( qreal angle )
 {
     m_angle = angle;
     invalidate();
 }
 
 qreal PrerenderedLabel::angle() const
 {
     return m_angle;
 }
 
 const QPixmap& PrerenderedLabel::pixmap() const
 {
     if ( m_dirty ) {
         INC_MISS_COUNT;
         paint();
     } else {
         INC_HIT_COUNT;
     }
     return m_pixmap;
 }
 
 void PrerenderedLabel::paint() const
 {
     // FIXME find a better value using font metrics of text (this
     // requires finding the diameter of the circle formed by rotating
     // the bounding rect around the center):
     const int Width = 1000;
     const int Height = Width;
 
     QRectF boundingRect;
     const QColor FullTransparent( 255, 255, 255, 0 );
 #ifdef Q_WS_X11
     QImage pixmap( Width, Height, QImage::Format_ARGB32_Premultiplied );
     qWarning() << "PrerenderedLabel::paint: using QImage for prerendered labels "
                << "to work around XRender/Qt4 bug.";
 #else
     QPixmap pixmap( Width, Height );
 #endif
     // pixmap.fill( FullTransparent );
     {
         static const QPointF Center ( 0.0, 0.0 );
         QPointF textBottomRight;
         QPainter painter( &pixmap );
         painter.setRenderHint(QPainter::TextAntialiasing, true );
         painter.setRenderHint(QPainter::Antialiasing, true );
 
         // QImage (X11 workaround) does not have fill():
         painter.setPen( FullTransparent );
         painter.setBrush( FullTransparent );
         QPainter::CompositionMode mode = painter.compositionMode();
         painter.setCompositionMode( QPainter::CompositionMode_Clear );
         painter.drawRect( 0, 0, Width, Height );
         painter.setCompositionMode( mode );
 
         QTransform matrix;
         matrix.translate( 0.5 * Width,  0.5 * Height );
         matrix.rotate( m_angle );
         painter.setWorldTransform( matrix );
 
         painter.setPen( m_pen );
         painter.setBrush( m_brush );
         painter.setFont( m_font );
         QRectF container( -0.5 * Width, -0.5 * Height, Width, 0.5 * Height );
         painter.drawText( container, Qt::AlignHCenter | Qt::AlignBottom,
                           m_text, &boundingRect );
         m_referenceBottomLeft = QPointF( boundingRect.bottomLeft().x(), 0.0 );
         textBottomRight = QPointF( boundingRect.bottomRight().x(), 0.0 );
         m_textAscendVector = boundingRect.topRight() - textBottomRight;
         m_textBaseLineVector = textBottomRight - m_referenceBottomLeft;
 
         // FIXME translate topright by char height
         boundingRect = matrix.mapRect( boundingRect );
         m_referenceBottomLeft = matrix.map( m_referenceBottomLeft )
                                 - boundingRect.topLeft();
         textBottomRight = matrix.map( textBottomRight )
                           - boundingRect.topLeft();
         m_textAscendVector = matrix.map( m_textAscendVector )
                              - matrix.map( Center );
         m_textBaseLineVector = matrix.map( m_textBaseLineVector )
                             - matrix.map( Center );
     }
 
     m_dirty = false; // now all the calculation vectors are valid
 
     QPixmap temp( static_cast<int>( boundingRect.width() ),
                   static_cast<int>( boundingRect.height() ) );
     {
         temp.fill( FullTransparent );
         QPainter painter( &temp );
 #ifdef Q_WS_X11
         painter.drawImage( QPointF( 0.0, 0.0 ), pixmap, boundingRect );
 #else
         painter.drawPixmap( QPointF( 0.0, 0.0 ), pixmap, boundingRect );
 #endif
 // #define PRERENDEREDLABEL_DEBUG
 #ifdef PRERENDEREDLABEL_DEBUG
         painter.setPen( QPen( Qt::red, 2 ) );
         painter.setBrush( Qt::red );
         // paint markers for the reference points
         QList<KChartEnums::PositionValue> positions;
         positions << KChartEnums::PositionCenter
                   << KChartEnums::PositionNorthWest
                   << KChartEnums::PositionNorth
                   << KChartEnums::PositionNorthEast
                   << KChartEnums::PositionEast
                   << KChartEnums::PositionSouthEast
                   << KChartEnums::PositionSouth
                   << KChartEnums::PositionSouthWest
                   << KChartEnums::PositionWest;
         for ( KChartEnums::PositionValue position : qAsConst(positions) ) { //krazy:exclude=foreach
             static const double Radius = 0.5;
             static const double Diameter = 2 * Radius;
 
             QPointF point ( referencePointLocation( position ) );
             painter.drawEllipse( QRectF( point - QPointF( Radius, Radius ),
                                          QSizeF( Diameter, Diameter ) ) );
         }
 #endif
     }
 
     m_pixmap = temp;
 }
 
 QPointF PrerenderedLabel::referencePointLocation() const
 {
     return referencePointLocation( referencePoint() );
 }
 
 QPointF PrerenderedLabel::referencePointLocation( KChartEnums::PositionValue position ) const
 {
     if ( m_dirty ) {
         INC_MISS_COUNT;
         paint();
     } else {
         INC_HIT_COUNT;
     }
 
     switch ( position ) {
     case KChartEnums::PositionCenter:
         return m_referenceBottomLeft + 0.5 * m_textBaseLineVector + 0.5 * m_textAscendVector;
     case KChartEnums::PositionNorthWest:
         return m_referenceBottomLeft + m_textAscendVector;
     case KChartEnums::PositionNorth:
         return m_referenceBottomLeft + 0.5 * m_textBaseLineVector + m_textAscendVector;
     case KChartEnums::PositionNorthEast:
         return m_referenceBottomLeft + m_textBaseLineVector + m_textAscendVector;
     case KChartEnums::PositionEast:
         return m_referenceBottomLeft + 0.5 * m_textAscendVector;
     case KChartEnums::PositionSouthEast:
         return m_referenceBottomLeft + m_textBaseLineVector;
     case KChartEnums::PositionSouth:
         return m_referenceBottomLeft + 0.5 * m_textBaseLineVector;
     case KChartEnums::PositionSouthWest:
         return m_referenceBottomLeft;
     case KChartEnums::PositionWest:
         return m_referenceBottomLeft + m_textBaseLineVector + 0.5 * m_textAscendVector;
 
     case KChartEnums::PositionUnknown: // intentional fall-through
     case KChartEnums::PositionFloating: // intentional fall-through
         return QPointF(); 
     }
     
     return QPointF();
 }