QGIS API Documentation  3.20.0-Odense (decaadbb31)
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 "qgslinesymbol.h"
22 #include "qgstextrenderer.h"
23 #include <QPainter>
24 
26  : mTickPosition( position )
27 {
28 
29 }
30 
32 {
33  switch ( mTickPosition )
34  {
35  case TicksUp:
36  return QStringLiteral( "Line Ticks Up" );
37  case TicksDown:
38  return QStringLiteral( "Line Ticks Down" );
39  case TicksMiddle:
40  return QStringLiteral( "Line Ticks Middle" );
41  }
42  return QString(); // to make gcc happy
43 }
44 
46 {
47  switch ( mTickPosition )
48  {
49  case TicksUp:
50  return QObject::tr( "Line Ticks Up" );
51  case TicksDown:
52  return QObject::tr( "Line Ticks Down" );
53  case TicksMiddle:
54  return QObject::tr( "Line Ticks Middle" );
55  }
56  return QString(); // to make gcc happy
57 
58 }
59 
61 {
62  switch ( mTickPosition )
63  {
64  case TicksUp:
65  return 5;
66  case TicksDown:
67  return 4;
68  case TicksMiddle:
69  return 3;
70  }
71  return 6;
72 }
73 
74 QgsScaleBarRenderer::Flags QgsTicksScaleBarRenderer::flags() const
75 {
88 }
89 
91 {
92  return new QgsTicksScaleBarRenderer( * this );
93 }
94 
95 void QgsTicksScaleBarRenderer::draw( QgsRenderContext &context, const QgsScaleBarSettings &settings, const ScaleBarContext &scaleContext ) const
96 {
97  if ( !context.painter() )
98  return;
99 
100  QPainter *painter = context.painter();
101 
102  const double scaledLabelBarSpace = context.convertToPainterUnits( settings.labelBarSpace(), QgsUnitTypes::RenderMillimeters );
103  const double scaledBoxContentSpace = context.convertToPainterUnits( settings.boxContentSpace(), QgsUnitTypes::RenderMillimeters );
104  const QFontMetricsF fontMetrics = QgsTextRenderer::fontMetrics( context, settings.textFormat() );
105  const double barTopPosition = scaledBoxContentSpace + ( settings.labelVerticalPlacement() == QgsScaleBarSettings::LabelAboveSegment ? fontMetrics.ascent() + scaledLabelBarSpace : 0 );
106  const double scaledHeight = context.convertToPainterUnits( settings.height(), QgsUnitTypes::RenderMillimeters );
107  const double scaledSubdivisionsHeight = context.convertToPainterUnits( settings.subdivisionsHeight(), QgsUnitTypes::RenderMillimeters );
108  const double scaledMaxHeight = ( ( settings.numberOfSubdivisions() > 1 ) && ( scaledSubdivisionsHeight > scaledHeight ) ) ? scaledSubdivisionsHeight : scaledHeight;
109  const double middlePosition = barTopPosition + scaledMaxHeight / 2.0;
110  const double bottomPosition = barTopPosition + scaledMaxHeight;
111 
112  const double xOffset = firstLabelXOffset( settings, context, scaleContext );
113 
114  painter->save();
115  context.setPainterFlagsUsingContext( painter );
116 
117  std::unique_ptr< QgsLineSymbol > symbol( settings.lineSymbol()->clone() );
118  symbol->startRender( context );
119 
120  std::unique_ptr< QgsLineSymbol > divisionSymbol( settings.divisionLineSymbol()->clone() );
121  divisionSymbol->startRender( context );
122 
123  std::unique_ptr< QgsLineSymbol > subdivisionSymbol( settings.subdivisionLineSymbol()->clone() );
124  subdivisionSymbol->startRender( context );
125 
126  const QList<double> positions = segmentPositions( context, scaleContext, settings );
127 
128  // vertical positions
129  double verticalPos = 0.0;
130  QList<double> subTickPositionsY;
131  QList<double> tickPositionsY;
132  switch ( mTickPosition )
133  {
134  case TicksDown:
135  verticalPos = barTopPosition;
136  subTickPositionsY << verticalPos;
137  subTickPositionsY << verticalPos + scaledSubdivisionsHeight;
138  tickPositionsY << verticalPos;
139  tickPositionsY << verticalPos + scaledHeight;
140  break;
141  case TicksMiddle:
142  verticalPos = middlePosition;
143  subTickPositionsY << verticalPos + scaledSubdivisionsHeight / 2.0;
144  subTickPositionsY << verticalPos - scaledSubdivisionsHeight / 2.0;
145  tickPositionsY << verticalPos + scaledHeight / 2.0;
146  tickPositionsY << verticalPos - scaledHeight / 2.0;
147  break;
148  case TicksUp:
149  verticalPos = bottomPosition;
150  subTickPositionsY << verticalPos;
151  subTickPositionsY << verticalPos - scaledSubdivisionsHeight;
152  tickPositionsY << verticalPos;
153  tickPositionsY << verticalPos - scaledHeight;
154  break;
155  }
156 
157  int symbolLayerCount = symbol->symbolLayerCount();
158  symbolLayerCount = std::max( symbolLayerCount, divisionSymbol->symbolLayerCount() );
159  symbolLayerCount = std::max( symbolLayerCount, subdivisionSymbol->symbolLayerCount() );
160 
161  // we render the bar symbol-layer-by-symbol-layer, to avoid ugliness where the lines overlap in multi-layer symbols
162  for ( int layer = 0; layer < symbolLayerCount; ++ layer )
163  {
164  const bool drawDivisionsForThisSymbolLayer = layer < divisionSymbol->symbolLayerCount();
165  const bool drawSubdivisionsForThisSymbolLayer = layer < subdivisionSymbol->symbolLayerCount();
166  const bool drawLineForThisSymbolLayer = layer < symbol->symbolLayerCount();
167 
168  if ( drawDivisionsForThisSymbolLayer )
169  {
170  // first draw the vertical lines for segments
171  for ( int i = 0; i < positions.size(); ++i )
172  {
173  const double thisX = context.convertToPainterUnits( positions.at( i ), QgsUnitTypes::RenderMillimeters ) + xOffset;
174  divisionSymbol->renderPolyline( QPolygonF() << QPointF( thisX, tickPositionsY.at( 0 ) )
175  << QPointF( thisX, tickPositionsY.at( 1 ) ), nullptr, context, layer );
176  }
177  }
178 
179  // draw the vertical lines for right subdivisions
180  if ( drawSubdivisionsForThisSymbolLayer )
181  {
182  for ( int i = settings.numberOfSegmentsLeft(); i < positions.size(); ++i )
183  {
184  for ( int j = 1; j < settings.numberOfSubdivisions(); ++j )
185  {
186  const double thisSubX = context.convertToPainterUnits( positions.at( i ) + j * scaleContext.segmentWidth / settings.numberOfSubdivisions(), QgsUnitTypes::RenderMillimeters ) + xOffset;
187  subdivisionSymbol->renderPolyline( QPolygonF() << QPointF( thisSubX, subTickPositionsY.at( 0 ) )
188  << QPointF( thisSubX, subTickPositionsY.at( 1 ) ), nullptr, context, layer );
189  }
190  }
191  }
192 
193  //draw last tick and horizontal line
194  if ( !positions.isEmpty() )
195  {
196  double lastTickPositionX = context.convertToPainterUnits( positions.at( positions.size() - 1 ) + scaleContext.segmentWidth, QgsUnitTypes::RenderMillimeters ) + xOffset;
197 
198  //last vertical line
199  if ( drawDivisionsForThisSymbolLayer )
200  {
201  divisionSymbol->renderPolyline( QPolygonF() << QPointF( lastTickPositionX, tickPositionsY.at( 0 ) )
202  << QPointF( lastTickPositionX, tickPositionsY.at( 1 ) ),
203  nullptr, context, layer );
204  }
205 
206  //horizontal line
207  if ( drawLineForThisSymbolLayer )
208  {
209  symbol->renderPolyline( QPolygonF() << QPointF( xOffset + context.convertToPainterUnits( positions.at( 0 ), QgsUnitTypes::RenderMillimeters ), verticalPos )
210  << QPointF( lastTickPositionX, verticalPos ), nullptr, context, layer );
211  }
212  }
213  }
214 
215  symbol->stopRender( context );
216  divisionSymbol->stopRender( context );
217  subdivisionSymbol->stopRender( context );
218 
219  painter->restore();
220 
221  //draw labels using the default method
222  drawDefaultLabels( context, settings, scaleContext );
223 }
224 
225 
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()) 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:169
Contains parameters regarding scalebar calculations.
double segmentWidth
The width, in millimeters, of each individual segment drawn.