QGIS API Documentation  2.99.0-Master (e077efd)
qgslegendsettings.cpp
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1 /***************************************************************************
2  qgslegendsettings.cpp
3  --------------------------------------
4  Date : July 2014
5  Copyright : (C) 2014 by Martin Dobias
6  Email : wonder dot sk at gmail dot com
7  ***************************************************************************
8  * *
9  * This program is free software; you can redistribute it and/or modify *
10  * it under the terms of the GNU General Public License as published by *
11  * the Free Software Foundation; either version 2 of the License, or *
12  * (at your option) any later version. *
13  * *
14  ***************************************************************************/
15 
16 #include "qgslegendsettings.h"
17 
18 #include <QPainter>
19 
21  : mTitle( QObject::tr( "Legend" ) )
22  , mTitleAlignment( Qt::AlignLeft )
23  , mWrapChar( QLatin1String( "" ) )
24  , mFontColor( QColor( 0, 0, 0 ) )
25  , mBoxSpace( 2 )
26  , mSymbolSize( 7, 4 )
27  , mWmsLegendSize( 50, 25 )
28  , mLineSpacing( 1.5 )
29  , mColumnSpace( 2 )
30  , mColumnCount( 1 )
31  , mSplitLayer( false )
32  , mEqualColumnWidth( false )
33  , mRasterSymbolBorder( true )
34  , mRasterBorderColor( Qt::black )
35  , mRasterBorderWidth( 0.0 )
36  , mMmPerMapUnit( 1 )
37  , mUseAdvancedEffects( true )
38  , mMapScale( 1 )
39  , mDpi( 96 ) // based on QImage's default DPI
40 {
47  rstyle( QgsComposerLegendStyle::Title ).rfont().setPointSizeF( 16.0 );
48  rstyle( QgsComposerLegendStyle::Group ).rfont().setPointSizeF( 14.0 );
49  rstyle( QgsComposerLegendStyle::Subgroup ).rfont().setPointSizeF( 12.0 );
50  rstyle( QgsComposerLegendStyle::SymbolLabel ).rfont().setPointSizeF( 12.0 );
51 }
52 
53 QStringList QgsLegendSettings::splitStringForWrapping( const QString& stringToSplt ) const
54 {
55  QStringList list;
56  // If the string contains nothing then just return the string without spliting.
57  if ( wrapChar().count() == 0 )
58  list << stringToSplt;
59  else
60  list = stringToSplt.split( wrapChar() );
61  return list;
62 }
63 
64 #define FONT_WORKAROUND_SCALE 10 //scale factor for upscaling fontsize and downscaling painter
65 
66 
67 void QgsLegendSettings::drawText( QPainter* p, double x, double y, const QString& text, const QFont& font ) const
68 {
69  QFont textFont = scaledFontPixelSize( font );
70 
71  p->save();
72  p->setFont( textFont );
73  double scaleFactor = 1.0 / FONT_WORKAROUND_SCALE;
74  p->scale( scaleFactor, scaleFactor );
75  p->drawText( QPointF( x * FONT_WORKAROUND_SCALE, y * FONT_WORKAROUND_SCALE ), text );
76  p->restore();
77 }
78 
79 
80 void QgsLegendSettings::drawText( QPainter* p, const QRectF& rect, const QString& text, const QFont& font, Qt::AlignmentFlag halignment, Qt::AlignmentFlag valignment, int flags ) const
81 {
82  QFont textFont = scaledFontPixelSize( font );
83 
84  QRectF scaledRect( rect.x() * FONT_WORKAROUND_SCALE, rect.y() * FONT_WORKAROUND_SCALE,
85  rect.width() * FONT_WORKAROUND_SCALE, rect.height() * FONT_WORKAROUND_SCALE );
86 
87  p->save();
88  p->setFont( textFont );
89  double scaleFactor = 1.0 / FONT_WORKAROUND_SCALE;
90  p->scale( scaleFactor, scaleFactor );
91  p->drawText( scaledRect, halignment | valignment | flags, text );
92  p->restore();
93 }
94 
95 
96 QFont QgsLegendSettings::scaledFontPixelSize( const QFont& font ) const
97 {
98  QFont scaledFont = font;
99  double pixelSize = pixelFontSize( font.pointSizeF() ) * FONT_WORKAROUND_SCALE + 0.5;
100  scaledFont.setPixelSize( pixelSize );
101  return scaledFont;
102 }
103 
104 double QgsLegendSettings::pixelFontSize( double pointSize ) const
105 {
106  return ( pointSize * 0.3527 );
107 }
108 
109 double QgsLegendSettings::textWidthMillimeters( const QFont& font, const QString& text ) const
110 {
111  QFont metricsFont = scaledFontPixelSize( font );
112  QFontMetricsF fontMetrics( metricsFont );
113  return ( fontMetrics.width( text ) / FONT_WORKAROUND_SCALE );
114 }
115 
116 double QgsLegendSettings::fontHeightCharacterMM( const QFont& font, QChar c ) const
117 {
118  QFont metricsFont = scaledFontPixelSize( font );
119  QFontMetricsF fontMetrics( metricsFont );
120  return ( fontMetrics.boundingRect( c ).height() / FONT_WORKAROUND_SCALE );
121 }
122 
123 double QgsLegendSettings::fontAscentMillimeters( const QFont& font ) const
124 {
125  QFont metricsFont = scaledFontPixelSize( font );
126  QFontMetricsF fontMetrics( metricsFont );
127  return ( fontMetrics.ascent() / FONT_WORKAROUND_SCALE );
128 }
129 
130 double QgsLegendSettings::fontDescentMillimeters( const QFont& font ) const
131 {
132  QFont metricsFont = scaledFontPixelSize( font );
133  QFontMetricsF fontMetrics( metricsFont );
134  return ( fontMetrics.descent() / FONT_WORKAROUND_SCALE );
135 }
136 
double pixelFontSize(double pointSize) const
Calculates font to from point size to pixel size.
void drawText(QPainter *p, double x, double y, const QString &text, const QFont &font) const
Draws Text.
double fontAscentMillimeters(const QFont &font) const
Returns the font ascent in Millimeters (considers upscaling and downscaling with FONT_WORKAROUND_SCAL...
QgsComposerLegendStyle & rstyle(QgsComposerLegendStyle::Style s)
Returns reference to modifiable style.
void setMargin(Side side, double margin)
QString wrapChar() const
QStringList splitStringForWrapping(const QString &stringToSplt) const
Splits a string using the wrap char taking into account handling empty wrap char which means no wrapp...
double textWidthMillimeters(const QFont &font, const QString &text) const
Returns the font width in millimeters (considers upscaling and downscaling with FONT_WORKAROUND_SCALE...
QFont scaledFontPixelSize(const QFont &font) const
Returns a font where size is in pixel and font size is upscaled with FONT_WORKAROUND_SCALE.
double fontHeightCharacterMM(const QFont &font, QChar c) const
Returns the font height of a character in millimeters.
#define FONT_WORKAROUND_SCALE
double fontDescentMillimeters(const QFont &font) const
Returns the font descent in Millimeters (considers upscaling and downscaling with FONT_WORKAROUND_SCA...