QGIS API Documentation  3.27.0-Master (e113457133)
qgsnumericscalebarrenderer.cpp
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1 /***************************************************************************
2  qgsnumericscalebarrenderer.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 "qgsnumericformat.h"
21 #include "qgstextrenderer.h"
22 #include <QList>
23 #include <QPainter>
24 
26 {
27  return QStringLiteral( "Numeric" );
28 }
29 
31 {
32  return QObject::tr( "Numeric" );
33 }
34 
36 {
37  return 100;
38 }
39 
40 QgsScaleBarRenderer::Flags QgsNumericScaleBarRenderer::flags() const
41 {
43 }
44 
46 {
47  return new QgsNumericScaleBarRenderer( *this );
48 }
49 
50 void QgsNumericScaleBarRenderer::draw( QgsRenderContext &context, const QgsScaleBarSettings &settings, const ScaleBarContext &scaleContext ) const
51 {
52  if ( !context.painter() )
53  {
54  return;
55  }
56 
57  QPainter *painter = context.painter();
58 
59  const QgsScopedQPainterState painterState( painter );
60  context.setPainterFlagsUsingContext( painter );
61 
62  const double margin = context.convertToPainterUnits( settings.boxContentSpace(), QgsUnitTypes::RenderMillimeters );
63  //map scalebar alignment to Qt::AlignmentFlag type
65  switch ( settings.alignment() )
66  {
69  break;
72  break;
75  break;
76  }
77 
78  //text destination is item's rect, excluding the margin
79  const QRectF painterRect( margin, margin, context.convertToPainterUnits( scaleContext.size.width(), QgsUnitTypes::RenderMillimeters ) - 2 * margin,
80  context.convertToPainterUnits( scaleContext.size.height(), QgsUnitTypes::RenderMillimeters ) - 2 * margin );
81  QgsTextRenderer::drawText( painterRect, 0, hAlign, QStringList() << scaleText( scaleContext.scale, settings ), context, settings.textFormat() );
82 }
83 
85  const QgsScaleBarRenderer::ScaleBarContext &scaleContext ) const
86 {
87  const double painterToMm = 1.0 / context.convertToPainterUnits( 1, QgsUnitTypes::RenderMillimeters );
88 
89  const double textWidth = QgsTextRenderer::textWidth( context, settings.textFormat(), QStringList() << scaleText( scaleContext.scale, settings ) ) * painterToMm;
90  const double textHeight = QgsTextRenderer::textHeight( context, settings.textFormat(), QStringList() << scaleText( scaleContext.scale, settings ) ) * painterToMm;
91 
92  return QSizeF( 2 * settings.boxContentSpace() + textWidth,
93  textHeight + 2 * settings.boxContentSpace() );
94 }
95 
97 {
98  const QFont font = settings.textFormat().toQFont();
99 
100  const double textWidth = QgsLayoutUtils::textWidthMM( font, scaleText( scaleContext.scale, settings ) );
101  const double textHeight = QgsLayoutUtils::fontAscentMM( font );
102 
103  return QSizeF( 2 * settings.boxContentSpace() + textWidth,
104  textHeight + 2 * settings.boxContentSpace() );
105 }
106 
107 QString QgsNumericScaleBarRenderer::scaleText( double scale, const QgsScaleBarSettings &settings ) const
108 {
109  return "1:" + settings.numericFormat()->formatDouble( scale, QgsNumericFormatContext() );
110 }
static double fontAscentMM(const QFont &font)
Calculates a font ascent in millimeters, including workarounds for QT font rendering issues.
static double textWidthMM(const QFont &font, const QString &text)
Calculate a font width in millimeters for a text string, including workarounds for QT font rendering ...
A context for numeric formats.
virtual QString formatDouble(double value, const QgsNumericFormatContext &context) const =0
Returns a formatted string representation of a numeric double value.
A scale bar style that draws text in the form of '1:XXXXX'.
QgsNumericScaleBarRenderer()=default
Constructor for QgsNumericScaleBarRenderer.
Flags flags() const override
Returns the scalebar rendering flags, which dictates the renderer's behavior.
int sortKey() const override
Returns a sorting key value, where renderers with a lower sort key will be shown earlier in lists.
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 visibleName() const override
Returns the user friendly, translated name for the renderer.
QgsNumericScaleBarRenderer * clone() const override
Returns a clone of the renderer.
QString id() const override
Returns the unique ID for this renderer.
QSizeF calculateBoxSize(QgsRenderContext &context, const QgsScaleBarSettings &settings, const QgsScaleBarRenderer::ScaleBarContext &scaleContext) const override
Calculates the required box size (in millimeters) for a scalebar using the specified settings and sca...
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).
@ FlagUsesAlignment
Renderer uses the QgsScaleBarSettings::alignment() setting.
The QgsScaleBarSettings class stores the appearance and layout settings for scalebar drawing with Qgs...
const QgsNumericFormat * numericFormat() const
Returns the numeric format used for numbers in the scalebar.
Alignment alignment() const
Returns the scalebar alignment.
double boxContentSpace() const
Returns the spacing (margin) between the scalebar box and content in millimeters.
@ AlignLeft
Left aligned.
@ AlignMiddle
Center aligned.
@ AlignRight
Right aligned.
QgsTextFormat & textFormat()
Returns the text format used for drawing text in the scalebar.
Scoped object for saving and restoring a QPainter object's state.
QFont toQFont() const
Returns a QFont matching the relevant settings from this text format.
static double textWidth(const QgsRenderContext &context, const QgsTextFormat &format, const QStringList &textLines, QFontMetricsF *fontMetrics=nullptr)
Returns the width of a text based on a given format.
static void drawText(const QRectF &rect, double rotation, HAlignment alignment, const QStringList &textLines, QgsRenderContext &context, const QgsTextFormat &format, bool drawAsOutlines=true, VAlignment vAlignment=AlignTop, Qgis::TextRendererFlags flags=Qgis::TextRendererFlags())
Draws text within a rectangle using the specified settings.
HAlignment
Horizontal alignment.
@ AlignLeft
Left align.
@ AlignRight
Right align.
@ AlignCenter
Center align.
static double textHeight(const QgsRenderContext &context, const QgsTextFormat &format, const QStringList &textLines, DrawMode mode=Point, QFontMetricsF *fontMetrics=nullptr, Qgis::TextRendererFlags flags=Qgis::TextRendererFlags(), double maxLineWidth=0)
Returns the height of a text based on a given format.
@ RenderMillimeters
Millimeters.
Definition: qgsunittypes.h:169
Contains parameters regarding scalebar calculations.
QSizeF size
Destination size for scalebar.