QGIS API Documentation  3.18.1-Zürich (202f1bf7e5)
qgsticksscalebarrenderer.cpp
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1 /***************************************************************************
2  qgsticksscalebarrenderer.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 <QPainter>
23 
25  : mTickPosition( position )
26 {
27 
28 }
29 
31 {
32  switch ( mTickPosition )
33  {
34  case TicksUp:
35  return QStringLiteral( "Line Ticks Up" );
36  case TicksDown:
37  return QStringLiteral( "Line Ticks Down" );
38  case TicksMiddle:
39  return QStringLiteral( "Line Ticks Middle" );
40  }
41  return QString(); // to make gcc happy
42 }
43 
45 {
46  switch ( mTickPosition )
47  {
48  case TicksUp:
49  return QObject::tr( "Line Ticks Up" );
50  case TicksDown:
51  return QObject::tr( "Line Ticks Down" );
52  case TicksMiddle:
53  return QObject::tr( "Line Ticks Middle" );
54  }
55  return QString(); // to make gcc happy
56 
57 }
58 
60 {
61  switch ( mTickPosition )
62  {
63  case TicksUp:
64  return 5;
65  case TicksDown:
66  return 4;
67  case TicksMiddle:
68  return 3;
69  }
70  return 6;
71 }
72 
73 QgsScaleBarRenderer::Flags QgsTicksScaleBarRenderer::flags() const
74 {
87 }
88 
90 {
91  return new QgsTicksScaleBarRenderer( * this );
92 }
93 
94 void QgsTicksScaleBarRenderer::draw( QgsRenderContext &context, const QgsScaleBarSettings &settings, const ScaleBarContext &scaleContext ) const
95 {
96  if ( !context.painter() )
97  return;
98 
99  QPainter *painter = context.painter();
100 
101  const double scaledLabelBarSpace = context.convertToPainterUnits( settings.labelBarSpace(), QgsUnitTypes::RenderMillimeters );
102  const double scaledBoxContentSpace = context.convertToPainterUnits( settings.boxContentSpace(), QgsUnitTypes::RenderMillimeters );
103  const QFontMetricsF fontMetrics = QgsTextRenderer::fontMetrics( context, settings.textFormat() );
104  const double barTopPosition = scaledBoxContentSpace + ( settings.labelVerticalPlacement() == QgsScaleBarSettings::LabelAboveSegment ? fontMetrics.ascent() + scaledLabelBarSpace : 0 );
105  const double scaledHeight = context.convertToPainterUnits( settings.height(), QgsUnitTypes::RenderMillimeters );
106  const double scaledSubdivisionsHeight = context.convertToPainterUnits( settings.subdivisionsHeight(), QgsUnitTypes::RenderMillimeters );
107  const double scaledMaxHeight = ( ( settings.numberOfSubdivisions() > 1 ) && ( scaledSubdivisionsHeight > scaledHeight ) ) ? scaledSubdivisionsHeight : scaledHeight;
108  const double middlePosition = barTopPosition + scaledMaxHeight / 2.0;
109  const double bottomPosition = barTopPosition + scaledMaxHeight;
110 
111  const double xOffset = firstLabelXOffset( settings, context, scaleContext );
112 
113  painter->save();
114  context.setPainterFlagsUsingContext( painter );
115 
116  std::unique_ptr< QgsLineSymbol > symbol( settings.lineSymbol()->clone() );
117  symbol->startRender( context );
118 
119  std::unique_ptr< QgsLineSymbol > divisionSymbol( settings.divisionLineSymbol()->clone() );
120  divisionSymbol->startRender( context );
121 
122  std::unique_ptr< QgsLineSymbol > subdivisionSymbol( settings.subdivisionLineSymbol()->clone() );
123  subdivisionSymbol->startRender( context );
124 
125  const QList<double> positions = segmentPositions( context, scaleContext, settings );
126 
127  // vertical positions
128  double verticalPos = 0.0;
129  QList<double> subTickPositionsY;
130  QList<double> tickPositionsY;
131  switch ( mTickPosition )
132  {
133  case TicksDown:
134  verticalPos = barTopPosition;
135  subTickPositionsY << verticalPos;
136  subTickPositionsY << verticalPos + scaledSubdivisionsHeight;
137  tickPositionsY << verticalPos;
138  tickPositionsY << verticalPos + scaledHeight;
139  break;
140  case TicksMiddle:
141  verticalPos = middlePosition;
142  subTickPositionsY << verticalPos + scaledSubdivisionsHeight / 2.0;
143  subTickPositionsY << verticalPos - scaledSubdivisionsHeight / 2.0;
144  tickPositionsY << verticalPos + scaledHeight / 2.0;
145  tickPositionsY << verticalPos - scaledHeight / 2.0;
146  break;
147  case TicksUp:
148  verticalPos = bottomPosition;
149  subTickPositionsY << verticalPos;
150  subTickPositionsY << verticalPos - scaledSubdivisionsHeight;
151  tickPositionsY << verticalPos;
152  tickPositionsY << verticalPos - scaledHeight;
153  break;
154  }
155 
156  int symbolLayerCount = symbol->symbolLayerCount();
157  symbolLayerCount = std::max( symbolLayerCount, divisionSymbol->symbolLayerCount() );
158  symbolLayerCount = std::max( symbolLayerCount, subdivisionSymbol->symbolLayerCount() );
159 
160  // we render the bar symbol-layer-by-symbol-layer, to avoid ugliness where the lines overlap in multi-layer symbols
161  for ( int layer = 0; layer < symbolLayerCount; ++ layer )
162  {
163  const bool drawDivisionsForThisSymbolLayer = layer < divisionSymbol->symbolLayerCount();
164  const bool drawSubdivisionsForThisSymbolLayer = layer < subdivisionSymbol->symbolLayerCount();
165  const bool drawLineForThisSymbolLayer = layer < symbol->symbolLayerCount();
166 
167  if ( drawDivisionsForThisSymbolLayer )
168  {
169  // first draw the vertical lines for segments
170  for ( int i = 0; i < positions.size(); ++i )
171  {
172  const double thisX = context.convertToPainterUnits( positions.at( i ), QgsUnitTypes::RenderMillimeters ) + xOffset;
173  divisionSymbol->renderPolyline( QPolygonF() << QPointF( thisX, tickPositionsY.at( 0 ) )
174  << QPointF( thisX, tickPositionsY.at( 1 ) ), nullptr, context, layer );
175  }
176  }
177 
178  // draw the vertical lines for right subdivisions
179  if ( drawSubdivisionsForThisSymbolLayer )
180  {
181  for ( int i = settings.numberOfSegmentsLeft(); i < positions.size(); ++i )
182  {
183  for ( int j = 1; j < settings.numberOfSubdivisions(); ++j )
184  {
185  const double thisSubX = context.convertToPainterUnits( positions.at( i ) + j * scaleContext.segmentWidth / settings.numberOfSubdivisions(), QgsUnitTypes::RenderMillimeters ) + xOffset;
186  subdivisionSymbol->renderPolyline( QPolygonF() << QPointF( thisSubX, subTickPositionsY.at( 0 ) )
187  << QPointF( thisSubX, subTickPositionsY.at( 1 ) ), nullptr, context, layer );
188  }
189  }
190  }
191 
192  //draw last tick and horizontal line
193  if ( !positions.isEmpty() )
194  {
195  double lastTickPositionX = context.convertToPainterUnits( positions.at( positions.size() - 1 ) + scaleContext.segmentWidth, QgsUnitTypes::RenderMillimeters ) + xOffset;
196 
197  //last vertical line
198  if ( drawDivisionsForThisSymbolLayer )
199  {
200  divisionSymbol->renderPolyline( QPolygonF() << QPointF( lastTickPositionX, tickPositionsY.at( 0 ) )
201  << QPointF( lastTickPositionX, tickPositionsY.at( 1 ) ),
202  nullptr, context, layer );
203  }
204 
205  //horizontal line
206  if ( drawLineForThisSymbolLayer )
207  {
208  symbol->renderPolyline( QPolygonF() << QPointF( xOffset + context.convertToPainterUnits( positions.at( 0 ), QgsUnitTypes::RenderMillimeters ), verticalPos )
209  << QPointF( lastTickPositionX, verticalPos ), nullptr, context, layer );
210  }
211  }
212  }
213 
214  symbol->stopRender( context );
215  divisionSymbol->stopRender( context );
216  subdivisionSymbol->stopRender( context );
217 
218  painter->restore();
219 
220  //draw labels using the default method
221  drawDefaultLabels( context, settings, scaleContext );
222 }
223 
224 
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.
@ FlagUsesSubdivisionsHeight
Renderer uses the scalebar subdivisions height (see QgsScaleBarSettings::subdivisionsHeight() )
@ FlagUsesSubdivisionSymbol
Renderer utilizes the scalebar subdivision symbol (see QgsScaleBarSettings::subdivisionLineSymbol() )
@ FlagUsesSegments
Renderer uses the scalebar segments.
@ FlagUsesLabelBarSpace
Renderer uses the QgsScaleBarSettings::labelBarSpace() setting.
@ FlagRespectsMapUnitsPerScaleBarUnit
Renderer respects the QgsScaleBarSettings::mapUnitsPerScaleBarUnit() setting.
@ FlagRespectsUnits
Renderer respects the QgsScaleBarSettings::units() setting.
@ FlagUsesSubdivisions
Renderer uses the scalebar subdivisions (see QgsScaleBarSettings::numberOfSubdivisions() )
@ FlagUsesDivisionSymbol
Renderer utilizes the scalebar division symbol (see QgsScaleBarSettings::divisionLineSymbol() )
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...
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...
double subdivisionsHeight() const
Returns the scalebar subdivisions height (in millimeters) for segments included in the right part of ...
QgsLineSymbol * lineSymbol() const
Returns the line symbol used to render the scalebar (only used for some scalebar types).
QgsLineSymbol * subdivisionLineSymbol() const
Returns the line symbol used to render the scalebar subdivisions (only used for some scalebar types).
double boxContentSpace() const
Returns the spacing (margin) between the scalebar box and content in millimeters.
LabelVerticalPlacement labelVerticalPlacement() const
Returns the vertical placement of text labels.
int numberOfSubdivisions() const
Returns the number of subdivisions for segments included in the right part of the scalebar (only used...
@ 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).
int numberOfSegmentsLeft() const
Returns the number of segments included in the left part of the scalebar.
QgsLineSymbol * divisionLineSymbol() const
Returns the line symbol used to render the scalebar divisions (only used for some scalebar types).
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.
A scale bar that draws segments using short ticks.
@ TicksUp
Render ticks above line.
@ TicksMiddle
Render ticks crossing line.
@ TicksDown
Render ticks below line.
Flags flags() const override
Returns the scalebar rendering flags, which dictates the renderer's behavior.
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.
QgsTicksScaleBarRenderer(TickPosition position=TicksMiddle)
Constructor for QgsTicksScaleBarRenderer.
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.
QgsTicksScaleBarRenderer * clone() const override
Returns a clone of the renderer.
@ RenderMillimeters
Millimeters.
Definition: qgsunittypes.h:168
Contains parameters regarding scalebar calculations.
double segmentWidth
The width, in millimeters, of each individual segment drawn.