QGIS API Documentation  3.23.0-Master (c716e02dd3)
qgssingleboxscalebarrenderer.cpp
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1 /***************************************************************************
2  qgssingleboxscalebarrenderer.cpp
3  --------------------------------
4  begin : June 2008
5  copyright : (C) 2008 by Marco Hugentobler
6  email : [email protected]
7  ***************************************************************************/
8 /***************************************************************************
9  * *
10  * This program is free software; you can redistribute it and/or modify *
11  * it under the terms of the GNU General Public License as published by *
12  * the Free Software Foundation; either version 2 of the License, or *
13  * (at your option) any later version. *
14  * *
15  ***************************************************************************/
16 
18 #include "qgsscalebarsettings.h"
19 #include "qgslayoututils.h"
20 #include "qgssymbol.h"
21 #include "qgstextrenderer.h"
22 #include "qgslinesymbol.h"
23 #include "qgsfillsymbol.h"
24 #include <QList>
25 #include <QPainter>
26 
28 {
29  return QStringLiteral( "Single Box" );
30 }
31 
33 {
34  return QObject::tr( "Single Box" );
35 }
36 
38 {
39  return 1;
40 }
41 
42 QgsScaleBarRenderer::Flags QgsSingleBoxScaleBarRenderer::flags() const
43 {
54 }
55 
57 {
58  return new QgsSingleBoxScaleBarRenderer( *this );
59 }
60 
61 void QgsSingleBoxScaleBarRenderer::draw( QgsRenderContext &context, const QgsScaleBarSettings &settings, const ScaleBarContext &scaleContext ) const
62 {
63  if ( !context.painter() )
64  {
65  return;
66  }
67  QPainter *painter = context.painter();
68 
69  const double scaledLabelBarSpace = context.convertToPainterUnits( settings.labelBarSpace(), QgsUnitTypes::RenderMillimeters );
70  const double scaledBoxContentSpace = context.convertToPainterUnits( settings.boxContentSpace(), QgsUnitTypes::RenderMillimeters );
71  const QFontMetricsF fontMetrics = QgsTextRenderer::fontMetrics( context, settings.textFormat() );
72  const double barTopPosition = scaledBoxContentSpace + ( settings.labelVerticalPlacement() == QgsScaleBarSettings::LabelAboveSegment ? fontMetrics.ascent() + scaledLabelBarSpace : 0 );
73  const double barHeight = context.convertToPainterUnits( settings.height(), QgsUnitTypes::RenderMillimeters );
74 
75  painter->save();
76  context.setPainterFlagsUsingContext( painter );
77 
78  std::unique_ptr< QgsLineSymbol > lineSymbol( settings.lineSymbol()->clone() );
79  lineSymbol->startRender( context );
80 
81  std::unique_ptr< QgsFillSymbol > fillSymbol1( settings.fillSymbol()->clone() );
82  fillSymbol1->startRender( context );
83 
84  std::unique_ptr< QgsFillSymbol > fillSymbol2( settings.alternateFillSymbol()->clone() );
85  fillSymbol2->startRender( context );
86 
87  painter->setPen( Qt::NoPen );
88  painter->setBrush( Qt::NoBrush );
89 
90  bool useColor = true; //alternate brush color/white
91  const double xOffset = firstLabelXOffset( settings, context, scaleContext );
92 
93  const QList<double> positions = segmentPositions( context, scaleContext, settings );
94  const QList<double> widths = segmentWidths( scaleContext, settings );
95 
96  // draw the fill
97  double minX = 0;
98  double maxX = 0;
99  QgsFillSymbol *currentSymbol = nullptr;
100  for ( int i = 0; i < positions.size(); ++i )
101  {
102  if ( useColor ) //alternating colors
103  {
104  currentSymbol = fillSymbol1.get();
105  }
106  else //secondary fill
107  {
108  currentSymbol = fillSymbol2.get();
109  }
110 
111  const double thisX = context.convertToPainterUnits( positions.at( i ), QgsUnitTypes::RenderMillimeters ) + xOffset;
112  const double thisWidth = context.convertToPainterUnits( widths.at( i ), QgsUnitTypes::RenderMillimeters );
113 
114  if ( i == 0 )
115  minX = thisX;
116  if ( i == positions.size() - 1 )
117  maxX = thisX + thisWidth;
118 
119  const QRectF segmentRect( thisX, barTopPosition, thisWidth, barHeight );
120  currentSymbol->renderPolygon( QPolygonF()
121  << segmentRect.topLeft()
122  << segmentRect.topRight()
123  << segmentRect.bottomRight()
124  << segmentRect.bottomLeft()
125  << segmentRect.topLeft(), nullptr, nullptr, context );
126  useColor = !useColor;
127  }
128 
129  // and then the lines
130  // note that we do this layer-by-layer, to avoid ugliness where the lines touch the outer rect
131  for ( int layer = 0; layer < lineSymbol->symbolLayerCount(); ++layer )
132  {
133  for ( int i = 1; i < positions.size(); ++i )
134  {
135  const double lineX = context.convertToPainterUnits( positions.at( i ), QgsUnitTypes::RenderMillimeters ) + xOffset;
136  lineSymbol->renderPolyline( QPolygonF()
137  << QPointF( lineX, barTopPosition )
138  << QPointF( lineX, barTopPosition + barHeight ),
139  nullptr, context, layer );
140  }
141 
142  // outside line
143  lineSymbol->renderPolyline( QPolygonF()
144  << QPointF( minX, barTopPosition )
145  << QPointF( maxX, barTopPosition )
146  << QPointF( maxX, barTopPosition + barHeight )
147  << QPointF( minX, barTopPosition + barHeight )
148  << QPointF( minX, barTopPosition ),
149  nullptr, context, layer );
150  }
151 
152  lineSymbol->stopRender( context );
153  fillSymbol1->stopRender( context );
154  fillSymbol2->stopRender( context );
155  painter->restore();
156 
157  //draw labels using the default method
158  drawDefaultLabels( context, settings, scaleContext );
159 }
160 
161 
162 
A fill symbol type, for rendering Polygon and MultiPolygon geometries.
Definition: qgsfillsymbol.h:30
void renderPolygon(const QPolygonF &points, const QVector< QPolygonF > *rings, const QgsFeature *f, QgsRenderContext &context, int layer=-1, bool selected=false)
Renders the symbol using the given render context.
QgsFillSymbol * clone() const override
Returns a deep copy of this symbol.
QgsLineSymbol * clone() const override
Returns a deep copy of this symbol.
Contains information about the context of a rendering operation.
QPainter * painter()
Returns the destination QPainter for the render operation.
void setPainterFlagsUsingContext(QPainter *painter=nullptr) const
Sets relevant flags on a destination painter, using the flags and settings currently defined for the ...
double convertToPainterUnits(double size, QgsUnitTypes::RenderUnit unit, const QgsMapUnitScale &scale=QgsMapUnitScale(), Qgis::RenderSubcomponentProperty property=Qgis::RenderSubcomponentProperty::Generic) const
Converts a size from the specified units to painter units (pixels).
@ FlagUsesLabelVerticalPlacement
Renderer uses the QgsScaleBarSettings::labelVerticalPlacement() setting.
@ FlagUsesLabelHorizontalPlacement
Renderer uses the QgsScaleBarSettings::labelHorizontalPlacement() setting.
@ FlagUsesLineSymbol
Renderer utilizes the scalebar line symbol (see QgsScaleBarSettings::lineSymbol() )
@ FlagUsesUnitLabel
Renderer uses the QgsScaleBarSettings::unitLabel() setting.
@ FlagUsesSegments
Renderer uses the scalebar segments.
@ FlagUsesLabelBarSpace
Renderer uses the QgsScaleBarSettings::labelBarSpace() setting.
@ FlagUsesFillSymbol
Renderer utilizes the scalebar fill symbol (see QgsScaleBarSettings::fillSymbol() )
@ FlagRespectsMapUnitsPerScaleBarUnit
Renderer respects the QgsScaleBarSettings::mapUnitsPerScaleBarUnit() setting.
@ FlagRespectsUnits
Renderer respects the QgsScaleBarSettings::units() setting.
@ FlagUsesAlternateFillSymbol
Renderer utilizes the alternate scalebar fill symbol (see QgsScaleBarSettings::alternateFillSymbol() ...
void drawDefaultLabels(QgsRenderContext &context, const QgsScaleBarSettings &settings, const QgsScaleBarRenderer::ScaleBarContext &scaleContext) const
Draws default scalebar labels using the specified settings and scaleContext to a destination render c...
QList< double > segmentWidths(const QgsScaleBarRenderer::ScaleBarContext &scaleContext, const QgsScaleBarSettings &settings) const
Returns a list of widths of each segment of the scalebar.
Q_DECL_DEPRECATED QList< double > segmentPositions(const QgsScaleBarRenderer::ScaleBarContext &scaleContext, const QgsScaleBarSettings &settings) const
Returns a list of positions for each segment within the scalebar.
Q_DECL_DEPRECATED double firstLabelXOffset(const QgsScaleBarSettings &settings) const
Returns the x-offset (in millimeters) used for the first label in the scalebar.
The QgsScaleBarSettings class stores the appearance and layout settings for scalebar drawing with Qgs...
QgsLineSymbol * lineSymbol() const
Returns the line symbol used to render the scalebar (only used for some scalebar types).
double boxContentSpace() const
Returns the spacing (margin) between the scalebar box and content in millimeters.
QgsFillSymbol * alternateFillSymbol() const
Returns the secondary fill symbol used to render the scalebar (only used for some scalebar types).
QgsFillSymbol * fillSymbol() const
Returns the primary fill symbol used to render the scalebar (only used for some scalebar types).
LabelVerticalPlacement labelVerticalPlacement() const
Returns the vertical placement of text labels.
@ LabelAboveSegment
Labels are drawn above the scalebar.
double labelBarSpace() const
Returns the spacing (in millimeters) between labels and the scalebar.
QgsTextFormat & textFormat()
Returns the text format used for drawing text in the scalebar.
double height() const
Returns the scalebar height (in millimeters).
Scalebar style that draws a single box with alternating color for the segments.
QString id() const override
Returns the unique ID for this renderer.
QgsSingleBoxScaleBarRenderer()=default
Constructor for QgsSingleBoxScaleBarRenderer.
QString visibleName() const override
Returns the user friendly, translated name for the renderer.
int sortKey() const override
Returns a sorting key value, where renderers with a lower sort key will be shown earlier in lists.
Flags flags() const override
Returns the scalebar rendering flags, which dictates the renderer's behavior.
QgsSingleBoxScaleBarRenderer * clone() const override
Returns a clone of the renderer.
void draw(QgsRenderContext &context, const QgsScaleBarSettings &settings, const QgsScaleBarRenderer::ScaleBarContext &scaleContext) const override
Draws the scalebar using the specified settings and scaleContext to a destination render context.
static QFontMetricsF fontMetrics(QgsRenderContext &context, const QgsTextFormat &format, double scaleFactor=1.0)
Returns the font metrics for the given text format, when rendered in the specified render context.
@ RenderMillimeters
Millimeters.
Definition: qgsunittypes.h:169
Contains parameters regarding scalebar calculations.