QGIS API Documentation  3.18.1-Zürich (202f1bf7e5)
qgsdoubleboxscalebarrenderer.cpp
Go to the documentation of this file.
1 /***************************************************************************
2  qgsdoubleboxscalebarrenderer.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 <QList>
23 #include <QPainter>
24 
26 {
27  return QStringLiteral( "Double Box" );
28 }
29 
31 {
32  return QObject::tr( "Double Box" );
33 }
34 
35 QgsScaleBarRenderer::Flags QgsDoubleBoxScaleBarRenderer::flags() const
36 {
47 }
48 
50 {
51  return 2;
52 }
53 
55 {
56  return new QgsDoubleBoxScaleBarRenderer( *this );
57 }
58 
59 void QgsDoubleBoxScaleBarRenderer::draw( QgsRenderContext &context, const QgsScaleBarSettings &settings, const ScaleBarContext &scaleContext ) const
60 {
61  if ( !context.painter() )
62  {
63  return;
64  }
65  QPainter *painter = context.painter();
66 
67  const double scaledLabelBarSpace = context.convertToPainterUnits( settings.labelBarSpace(), QgsUnitTypes::RenderMillimeters );
68  const double scaledBoxContentSpace = context.convertToPainterUnits( settings.boxContentSpace(), QgsUnitTypes::RenderMillimeters );
69  const QFontMetricsF fontMetrics = QgsTextRenderer::fontMetrics( context, settings.textFormat() );
70  const double barTopPosition = scaledBoxContentSpace + ( settings.labelVerticalPlacement() == QgsScaleBarSettings::LabelAboveSegment ? fontMetrics.ascent() + scaledLabelBarSpace : 0 );
71  const double segmentHeight = context.convertToPainterUnits( settings.height() / 2, QgsUnitTypes::RenderMillimeters );
72 
73  painter->save();
74  context.setPainterFlagsUsingContext( painter );
75 
76  std::unique_ptr< QgsLineSymbol > lineSymbol( settings.lineSymbol()->clone() );
77  lineSymbol->startRender( context );
78 
79  std::unique_ptr< QgsFillSymbol > fillSymbol1( settings.fillSymbol()->clone() );
80  fillSymbol1->startRender( context );
81 
82  std::unique_ptr< QgsFillSymbol > fillSymbol2( settings.alternateFillSymbol()->clone() );
83  fillSymbol2->startRender( context );
84 
85  painter->setPen( Qt::NoPen );
86  painter->setBrush( Qt::NoBrush );
87 
88  bool useColor = true; //alternate brush color/white
89 
90  const double xOffset = firstLabelXOffset( settings, context, scaleContext );
91 
92  const QList<double> positions = segmentPositions( context, scaleContext, settings );
93  const QList<double> widths = segmentWidths( scaleContext, settings );
94 
95  double minX = 0;
96  double maxX = 0;
97  QgsFillSymbol *currentSymbol = nullptr;
98  for ( int i = 0; i < positions.size(); ++i )
99  {
100  //draw top half
101  if ( useColor )
102  {
103  currentSymbol = fillSymbol1.get();
104  }
105  else //secondary symbol
106  {
107  currentSymbol = fillSymbol2.get();
108  }
109 
110  const double thisX = context.convertToPainterUnits( positions.at( i ), QgsUnitTypes::RenderMillimeters ) + xOffset;
111  const double thisWidth = context.convertToPainterUnits( widths.at( i ), QgsUnitTypes::RenderMillimeters );
112 
113  if ( i == 0 )
114  minX = thisX;
115  if ( i == positions.size() - 1 )
116  maxX = thisX + thisWidth;
117 
118  const QRectF segmentRectTop( thisX, barTopPosition, thisWidth, segmentHeight );
119  currentSymbol->renderPolygon( QPolygonF()
120  << segmentRectTop.topLeft()
121  << segmentRectTop.topRight()
122  << segmentRectTop.bottomRight()
123  << segmentRectTop.bottomLeft()
124  << segmentRectTop.topLeft(),
125  nullptr, nullptr, context );
126  painter->drawRect( segmentRectTop );
127 
128  //draw bottom half
129  if ( useColor )
130  {
131  //secondary symbol
132  currentSymbol = fillSymbol2.get();
133  }
134  else //primary symbol
135  {
136  currentSymbol = fillSymbol1.get(); ;
137  }
138 
139  const QRectF segmentRectBottom( thisX, barTopPosition + segmentHeight, thisWidth, segmentHeight );
140 
141  currentSymbol->renderPolygon( QPolygonF()
142  << segmentRectBottom.topLeft()
143  << segmentRectBottom.topRight()
144  << segmentRectBottom.bottomRight()
145  << segmentRectBottom.bottomLeft()
146  << segmentRectBottom.topLeft(),
147  nullptr, nullptr, context );
148  useColor = !useColor;
149  }
150 
151 
152  // and then the lines
153  // note that we do this layer-by-layer, to avoid ugliness where the lines touch the outer rect
154  for ( int layer = 0; layer < lineSymbol->symbolLayerCount(); ++layer )
155  {
156  // vertical lines
157  for ( int i = 1; i < positions.size(); ++i )
158  {
159  const double lineX = context.convertToPainterUnits( positions.at( i ), QgsUnitTypes::RenderMillimeters ) + xOffset;
160  lineSymbol->renderPolyline( QPolygonF()
161  << QPointF( lineX, barTopPosition )
162  << QPointF( lineX, barTopPosition + segmentHeight * 2 ),
163  nullptr, context, layer );
164  }
165 
166  // middle horizontal line
167  lineSymbol->renderPolyline( QPolygonF()
168  << QPointF( minX, barTopPosition + segmentHeight )
169  << QPointF( maxX, barTopPosition + segmentHeight ),
170  nullptr, context, layer );
171 
172 
173  // outside line
174  lineSymbol->renderPolyline( QPolygonF()
175  << QPointF( minX, barTopPosition )
176  << QPointF( maxX, barTopPosition )
177  << QPointF( maxX, barTopPosition + segmentHeight * 2 )
178  << QPointF( minX, barTopPosition + segmentHeight * 2 )
179  << QPointF( minX, barTopPosition ),
180  nullptr, context, layer );
181  }
182 
183  lineSymbol->stopRender( context );
184  fillSymbol1->stopRender( context );
185  fillSymbol2->stopRender( context );
186 
187  painter->restore();
188 
189  //draw labels using the default method
190  drawDefaultLabels( context, settings, scaleContext );
191 }
Double box with alternating colors.
Flags flags() const override
Returns the scalebar rendering flags, which dictates the renderer's behavior.
QgsDoubleBoxScaleBarRenderer()=default
Constructor for QgsDoubleBoxScaleBarRenderer.
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.
QString id() const override
Returns the unique ID for this renderer.
QString visibleName() const override
Returns the user friendly, translated name for the renderer.
QgsDoubleBoxScaleBarRenderer * clone() const override
Returns a clone of the renderer.
int sortKey() const override
Returns a sorting key value, where renderers with a lower sort key will be shown earlier in lists.
A fill symbol type, for rendering Polygon and MultiPolygon geometries.
Definition: qgssymbol.h:1307
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.
Definition: qgssymbol.cpp:2318
QgsFillSymbol * clone() const override
Returns a deep copy of this symbol.
Definition: qgssymbol.cpp:2422
QgsLineSymbol * clone() const override
Returns a deep copy of this symbol.
Definition: qgssymbol.cpp:2295
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()) 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).
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:168
Contains parameters regarding scalebar calculations.