QGIS API Documentation 3.29.0-Master (19d7edcfed)
qgslabellinesettings.cpp
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1/***************************************************************************
2 qgslabellinesettings.cpp
3 ----------------------------
4 Date : August 2020
5 Copyright : (C) 2020 by Nyall Dawson
6 Email : nyall dot dawson at gmail dot com
7 ***************************************************************************
8 * *
9 * This program is free software; you can redistribute it and/or modify *
10 * it under the terms of the GNU General Public License as published by *
11 * the Free Software Foundation; either version 2 of the License, or *
12 * (at your option) any later version. *
13 * *
14 ***************************************************************************/
15
19#include "qgslabelingengine.h"
20#include "qgspallabeling.h"
21
22
24{
26 {
28 const QString dataDefinedLineArrangement = properties.valueAsString( QgsPalLayerSettings::LinePlacementOptions, context );
29 if ( !dataDefinedLineArrangement.isEmpty() )
30 {
31 mPlacementFlags = QgsLabelingUtils::decodeLinePlacementFlags( dataDefinedLineArrangement );
32 }
33 }
34
36 {
37 context.setOriginalValueVariable( mOverrunDistance );
38 mOverrunDistance = properties.valueAsDouble( QgsPalLayerSettings::OverrunDistance, context, mOverrunDistance );
39 }
40
42 {
43 context.setOriginalValueVariable( mLineAnchorPercent );
44 mLineAnchorPercent = properties.valueAsDouble( QgsPalLayerSettings::LineAnchorPercent, context, mLineAnchorPercent );
45 }
46
48 {
49 bool ok = false;
50 const QString value = properties.valueAsString( QgsPalLayerSettings::LineAnchorClipping, context, QString(), &ok ).trimmed();
51 if ( ok )
52 {
53 if ( value.compare( QLatin1String( "visible" ), Qt::CaseInsensitive ) == 0 )
55 else if ( value.compare( QLatin1String( "entire" ), Qt::CaseInsensitive ) == 0 )
56 mAnchorClipping = AnchorClipping::UseEntireLine;
57 }
58 }
59
61 {
62 bool ok = false;
63 const QString value = properties.valueAsString( QgsPalLayerSettings::LineAnchorType, context, QString(), &ok ).trimmed();
64 if ( ok )
65 {
66 if ( value.compare( QLatin1String( "hint" ), Qt::CaseInsensitive ) == 0 )
67 mAnchorType = AnchorType::HintOnly;
68 else if ( value.compare( QLatin1String( "strict" ), Qt::CaseInsensitive ) == 0 )
69 mAnchorType = AnchorType::Strict;
70 }
71 }
72
74 {
75 bool ok = false;
76 const QString value = properties.valueAsString( QgsPalLayerSettings::LineAnchorTextPoint, context, QString(), &ok ).trimmed();
77 if ( ok )
78 {
79 if ( value.compare( QLatin1String( "follow" ), Qt::CaseInsensitive ) == 0 )
80 mAnchorTextPoint = AnchorTextPoint::FollowPlacement;
81 else if ( value.compare( QLatin1String( "start" ), Qt::CaseInsensitive ) == 0 )
82 mAnchorTextPoint = AnchorTextPoint::StartOfText;
83 else if ( value.compare( QLatin1String( "center" ), Qt::CaseInsensitive ) == 0 )
84 mAnchorTextPoint = AnchorTextPoint::CenterOfText;
85 else if ( value.compare( QLatin1String( "end" ), Qt::CaseInsensitive ) == 0 )
86 mAnchorTextPoint = AnchorTextPoint::EndOfText;
87 }
88 }
89}
double valueAsDouble(int key, const QgsExpressionContext &context, double defaultValue=0.0, bool *ok=nullptr) const
Calculates the current value of the property with the specified key and interprets it as a double.
QString valueAsString(int key, const QgsExpressionContext &context, const QString &defaultString=QString(), bool *ok=nullptr) const
Calculates the current value of the property with the specified key and interprets it as a string.
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
void setOriginalValueVariable(const QVariant &value)
Sets the original value variable value for the context.
@ Strict
Line anchor is a strict placement, and other placements are not permitted.
@ HintOnly
Line anchor is a hint for preferred placement only, but other placements close to the hint are permit...
@ UseEntireLine
Entire original feature line geometry is used when calculating the line anchor for labels.
@ UseVisiblePartsOfLine
Only visible parts of lines are considered when calculating the line anchor for labels.
@ EndOfText
Anchor using end of text.
@ StartOfText
Anchor using start of text.
@ CenterOfText
Anchor using center of text.
@ FollowPlacement
Automatically set the anchor point based on the lineAnchorPercent() value. Values <25% will use the s...
void updateDataDefinedProperties(const QgsPropertyCollection &properties, QgsExpressionContext &context)
Updates the thinning settings to respect any data defined properties set within the specified propert...
static QString encodeLinePlacementFlags(QgsLabeling::LinePlacementFlags flags)
Encodes line placement flags to a string.
static QgsLabeling::LinePlacementFlags decodeLinePlacementFlags(const QString &string)
Decodes a string to set of line placement flags.
@ OverrunDistance
Distance which labels can extend past either end of linear features.
@ LineAnchorPercent
Portion along line at which labels should be anchored (since QGIS 3.16)
@ LineAnchorType
Line anchor type (since QGIS 3.26)
@ LineAnchorClipping
Clipping mode for line anchor calculation (since QGIS 3.20)
@ LineAnchorTextPoint
Line anchor text point (since QGIS 3.26)
@ LinePlacementOptions
Line placement flags.
A grouped map of multiple QgsProperty objects, each referenced by a integer key value.
bool isActive(int key) const override
Returns true if the collection contains an active property with the specified key.