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qgsheatmaprendererwidget.cpp
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1 /***************************************************************************
2  qgsheatmaprendererwidget.cpp
3  ----------------------------
4  begin : November 2014
5  copyright : (C) 2014 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  ***************************************************************************/
16 #include "qgsheatmaprenderer.h"
17 #include "qgsrendererregistry.h"
19 
20 #include "qgssymbol.h"
21 
22 #include "qgslogger.h"
23 #include "qgsvectorlayer.h"
24 #include "qgscolorramp.h"
25 #include "qgscolorrampbutton.h"
26 #include "qgsstyle.h"
27 #include "qgsproject.h"
28 #include "qgsmapcanvas.h"
29 #include <QGridLayout>
30 #include <QLabel>
31 
33 {
34  return new QgsHeatmapRendererWidget( layer, style, renderer );
35 }
36 
37 QgsExpressionContext QgsHeatmapRendererWidget::createExpressionContext() const
38 {
39  QgsExpressionContext expContext;
43 
44  if ( mContext.mapCanvas() )
45  {
48  }
49  else
50  {
52  }
53 
54  if ( vectorLayer() )
56 
57  // additional scopes
58  const auto constAdditionalExpressionContextScopes = mContext.additionalExpressionContextScopes();
59  for ( const QgsExpressionContextScope &scope : constAdditionalExpressionContextScopes )
60  {
61  expContext.appendScope( new QgsExpressionContextScope( scope ) );
62  }
63 
64  return expContext;
65 }
66 
68  : QgsRendererWidget( layer, style )
69 
70 {
71  if ( !layer )
72  {
73  return;
74  }
75  // the renderer only applies to point vector layers
76  if ( layer->geometryType() != QgsWkbTypes::PointGeometry )
77  {
78  //setup blank dialog
79  mRenderer = nullptr;
80  QLabel *label = new QLabel( tr( "The heatmap renderer only applies to point and multipoint layers. \n"
81  "'%1' is not a point layer and cannot be rendered as a heatmap." )
82  .arg( layer->name() ), this );
83  if ( !layout() )
84  setLayout( new QGridLayout() );
85  layout()->addWidget( label );
86  return;
87  }
88 
89  setupUi( this );
90  connect( mRadiusUnitWidget, &QgsUnitSelectionWidget::changed, this, &QgsHeatmapRendererWidget::mRadiusUnitWidget_changed );
91  connect( mRadiusSpinBox, static_cast < void ( QDoubleSpinBox::* )( double ) > ( &QDoubleSpinBox::valueChanged ), this, &QgsHeatmapRendererWidget::mRadiusSpinBox_valueChanged );
92  connect( mMaxSpinBox, static_cast < void ( QDoubleSpinBox::* )( double ) > ( &QDoubleSpinBox::valueChanged ), this, &QgsHeatmapRendererWidget::mMaxSpinBox_valueChanged );
93  connect( mQualitySlider, &QSlider::valueChanged, this, &QgsHeatmapRendererWidget::mQualitySlider_valueChanged );
94  this->layout()->setContentsMargins( 0, 0, 0, 0 );
95 
98  mWeightExpressionWidget->registerExpressionContextGenerator( this );
99 
100  if ( renderer )
101  {
102  mRenderer = QgsHeatmapRenderer::convertFromRenderer( renderer );
103  }
104  if ( !mRenderer )
105  {
106  mRenderer = new QgsHeatmapRenderer();
107  }
108 
109  btnColorRamp->setShowGradientOnly( true );
110 
111  connect( btnColorRamp, &QgsColorRampButton::colorRampChanged, this, &QgsHeatmapRendererWidget::applyColorRamp );
112 
113  if ( mRenderer->colorRamp() )
114  {
115  btnColorRamp->blockSignals( true );
116  btnColorRamp->setColorRamp( mRenderer->colorRamp() );
117  btnColorRamp->blockSignals( false );
118  }
119  mRadiusSpinBox->blockSignals( true );
120  mRadiusSpinBox->setValue( mRenderer->radius() );
121  mRadiusSpinBox->blockSignals( false );
122  mRadiusUnitWidget->blockSignals( true );
123  mRadiusUnitWidget->setUnit( mRenderer->radiusUnit() );
124  mRadiusUnitWidget->setMapUnitScale( mRenderer->radiusMapUnitScale() );
125  mRadiusUnitWidget->blockSignals( false );
126  mMaxSpinBox->blockSignals( true );
127  mMaxSpinBox->setValue( mRenderer->maximumValue() );
128  mMaxSpinBox->blockSignals( false );
129  mQualitySlider->blockSignals( true );
130  mQualitySlider->setValue( mRenderer->renderQuality() );
131  mQualitySlider->blockSignals( false );
132 
133  mWeightExpressionWidget->setLayer( layer );
134  mWeightExpressionWidget->setField( mRenderer->weightExpression() );
135  connect( mWeightExpressionWidget, static_cast < void ( QgsFieldExpressionWidget::* )( const QString & ) >( &QgsFieldExpressionWidget::fieldChanged ), this, &QgsHeatmapRendererWidget::weightExpressionChanged );
136 }
137 
139 {
140  return mRenderer;
141 }
142 
144 {
146  if ( context.mapCanvas() )
147  mRadiusUnitWidget->setMapCanvas( context.mapCanvas() );
148 }
149 
150 void QgsHeatmapRendererWidget::applyColorRamp()
151 {
152  if ( !mRenderer )
153  {
154  return;
155  }
156 
157  QgsColorRamp *ramp = btnColorRamp->colorRamp();
158  if ( !ramp )
159  return;
160 
161  mRenderer->setColorRamp( ramp );
162  emit widgetChanged();
163 }
164 
165 void QgsHeatmapRendererWidget::mRadiusUnitWidget_changed()
166 {
167  if ( !mRenderer )
168  {
169  return;
170  }
171 
172  mRenderer->setRadiusUnit( mRadiusUnitWidget->unit() );
173  mRenderer->setRadiusMapUnitScale( mRadiusUnitWidget->getMapUnitScale() );
174  emit widgetChanged();
175 }
176 
177 void QgsHeatmapRendererWidget::mRadiusSpinBox_valueChanged( double d )
178 {
179  if ( !mRenderer )
180  {
181  return;
182  }
183 
184  mRenderer->setRadius( d );
185  emit widgetChanged();
186 }
187 
188 void QgsHeatmapRendererWidget::mMaxSpinBox_valueChanged( double d )
189 {
190  if ( !mRenderer )
191  {
192  return;
193  }
194 
195  mRenderer->setMaximumValue( d );
196  emit widgetChanged();
197 }
198 
199 void QgsHeatmapRendererWidget::mQualitySlider_valueChanged( int v )
200 {
201  if ( !mRenderer )
202  {
203  return;
204  }
205 
206  mRenderer->setRenderQuality( v );
207  emit widgetChanged();
208 }
209 
210 void QgsHeatmapRendererWidget::weightExpressionChanged( const QString &expression )
211 {
212  mRenderer->setWeightExpression( expression );
213  emit widgetChanged();
214 }
The QgsFieldExpressionWidget class reates a widget to choose fields and edit expressions It contains ...
virtual void setContext(const QgsSymbolWidgetContext &context)
Sets the context in which the renderer widget is shown, e.g., the associated map canvas and expressio...
double renderQuality() const
Returns the render quality used for drawing the heatmap.
void setColorRamp(QgsColorRamp *ramp)
Sets the color ramp to use for shading the heatmap.
QgsSymbolWidgetContext context() const
Returns the context in which the renderer widget is shown, e.g., the associated map canvas and expres...
void colorRampChanged()
Emitted whenever a new color ramp is set for the button.
Base class for renderer settings widgets.
static QgsRendererWidget * create(QgsVectorLayer *layer, QgsStyle *style, QgsFeatureRenderer *renderer)
Static creation method.
Abstract base class for color ramps.
Definition: qgscolorramp.h:31
double maximumValue() const
Returns the maximum value used for shading the heatmap.
Q_INVOKABLE QgsWkbTypes::GeometryType geometryType() const
Returns point, line or polygon.
void setWeightExpression(const QString &expression)
Sets the expression used for weighting points when generating the heatmap.
static QgsExpressionContextScope * projectScope(const QgsProject *project)
Creates a new scope which contains variables and functions relating to a QGIS project.
static QgsExpressionContextScope * atlasScope(const QgsLayoutAtlas *atlas)
Creates a new scope which contains variables and functions relating to a QgsLayoutAtlas.
QList< QgsUnitTypes::RenderUnit > RenderUnitList
List of render units.
Definition: qgsunittypes.h:218
The QgsMapSettings class contains configuration for rendering of the map.
QgsHeatmapRendererWidget(QgsVectorLayer *layer, QgsStyle *style, QgsFeatureRenderer *renderer)
Constructor.
static QgsExpressionContextScope * globalScope()
Creates a new scope which contains variables and functions relating to the global QGIS context...
A renderer which draws points as a live heatmap.
Contains settings which reflect the context in which a symbol (or renderer) widget is shown...
void setRadiusMapUnitScale(const QgsMapUnitScale &scale)
Sets the map unit scale used for the heatmap&#39;s radius.
double radius() const
Returns the radius for the heatmap.
const QgsMapUnitScale & radiusMapUnitScale() const
Returns the map unit scale used for the heatmap&#39;s radius.
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
const QgsVectorLayer * vectorLayer() const
Returns the vector layer associated with the widget.
QgsFeatureRenderer * renderer() override
Returns pointer to the renderer (no transfer of ownership)
QgsColorRamp * colorRamp() const
Returns the color ramp used for shading the heatmap.
Single scope for storing variables and functions for use within a QgsExpressionContext.
void setRenderQuality(const int quality)
Sets the render quality used for drawing the heatmap.
void widgetChanged()
Emitted when the widget state changes.
void setRadiusUnit(const QgsUnitTypes::RenderUnit unit)
Sets the units used for the heatmap&#39;s radius.
void setRadius(const double radius)
Sets the radius for the heatmap.
void fieldChanged(const QString &fieldName)
Emitted when the currently selected field changes.
const QgsMapSettings & mapSettings() const
Gets access to properties used for map rendering.
QgsMapCanvas * mapCanvas() const
Returns the map canvas associated with the widget.
static QgsExpressionContextScope * mapSettingsScope(const QgsMapSettings &mapSettings)
Creates a new scope which contains variables and functions relating to a QgsMapSettings object...
QgsSymbolWidgetContext mContext
Context in which widget is shown.
QgsExpressionContextScope & expressionContextScope()
Returns a reference to the expression context scope for the map canvas.
Definition: qgsmapcanvas.h:583
Points (e.g., for font sizes)
Definition: qgsunittypes.h:151
void appendScope(QgsExpressionContextScope *scope)
Appends a scope to the end of the context.
static QgsProject * instance()
Returns the QgsProject singleton instance.
Definition: qgsproject.cpp:450
static QgsHeatmapRenderer * convertFromRenderer(const QgsFeatureRenderer *renderer)
QString name
Definition: qgsmaplayer.h:83
static QgsExpressionContextScope * layerScope(const QgsMapLayer *layer)
Creates a new scope which contains variables and functions relating to a QgsMapLayer.
void setContext(const QgsSymbolWidgetContext &context) override
Sets the context in which the renderer widget is shown, e.g., the associated map canvas and expressio...
QString weightExpression() const
Returns the expression used for weighting points when generating the heatmap.
Represents a vector layer which manages a vector based data sets.
void setMaximumValue(const double value)
Sets the maximum value used for shading the heatmap.
QgsUnitTypes::RenderUnit radiusUnit() const
Returns the units used for the heatmap&#39;s radius.
QList< QgsExpressionContextScope > additionalExpressionContextScopes() const
Returns the list of additional expression context scopes to show as available within the layer...