QGIS API Documentation 3.27.0-Master (1d7a28cfd2)
qgsrasterrendererregistry.cpp
Go to the documentation of this file.
1/***************************************************************************
2 qgsrasterrendererregistry.cpp
3 -----------------------------
4 begin : January 2012
5 copyright : (C) 2012 by Marco Hugentobler
6 email : marco at sourcepole dot ch
7 ***************************************************************************/
8
9/***************************************************************************
10 * *
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU General Public License as published by *
13 * the Free Software Foundation; either version 2 of the License, or *
14 * (at your option) any later version. *
15 * *
16 ***************************************************************************/
17
20#include "qgsrastershader.h"
29#include "qgsapplication.h"
30#include "qgssettings.h"
31
32#include <QIcon>
33
34QgsRasterRendererRegistryEntry::QgsRasterRendererRegistryEntry( const QString &name, const QString &visibleName,
35 QgsRasterRendererCreateFunc rendererFunction,
37 : name( name )
38 , visibleName( visibleName )
39 , rendererCreateFunction( rendererFunction )
40 , widgetCreateFunction( widgetFunction )
41{
42}
43
45{
46 return QgsApplication::getThemeIcon( QString( "styleicons/%1.svg" ).arg( name ) );
47}
48
50{
51 // insert items in a particular order, which is returned in renderersList()
52 insert( QgsRasterRendererRegistryEntry( QStringLiteral( "multibandcolor" ), QObject::tr( "Multiband color" ),
54 insert( QgsRasterRendererRegistryEntry( QStringLiteral( "paletted" ), QObject::tr( "Paletted/Unique values" ), QgsPalettedRasterRenderer::create, nullptr ) );
55 insert( QgsRasterRendererRegistryEntry( QStringLiteral( "singlebandgray" ), QObject::tr( "Singleband gray" ),
57 insert( QgsRasterRendererRegistryEntry( QStringLiteral( "singlebandpseudocolor" ), QObject::tr( "Singleband pseudocolor" ),
59 insert( QgsRasterRendererRegistryEntry( QStringLiteral( "singlebandcolordata" ), QObject::tr( "Singleband color data" ),
61 insert( QgsRasterRendererRegistryEntry( QStringLiteral( "hillshade" ), QObject::tr( "Hillshade" ),
63 insert( QgsRasterRendererRegistryEntry( QStringLiteral( "contour" ), QObject::tr( "Contours" ),
65}
66
68{
69 mEntries.insert( entry.name, entry );
70 mSortedEntries.append( entry.name );
71}
72
74{
75 if ( !mEntries.contains( rendererName ) )
76 {
77 return;
78 }
79 mEntries[rendererName].widgetCreateFunction = func;
80}
81
82bool QgsRasterRendererRegistry::rendererData( const QString &rendererName, QgsRasterRendererRegistryEntry &data ) const
83{
84 const QHash< QString, QgsRasterRendererRegistryEntry >::const_iterator it = mEntries.find( rendererName );
85 if ( it == mEntries.constEnd() )
86 {
87 return false;
88 }
89 data = it.value();
90 return true;
91}
92
94{
95 return mSortedEntries;
96}
97
98QList< QgsRasterRendererRegistryEntry > QgsRasterRendererRegistry::entries() const
99{
100 QList< QgsRasterRendererRegistryEntry > result;
101
102 QHash< QString, QgsRasterRendererRegistryEntry >::const_iterator it = mEntries.constBegin();
103 for ( ; it != mEntries.constEnd(); ++it )
104 {
105 result.push_back( it.value() );
106 }
107 return result;
108}
109
111{
112 if ( !provider || provider->bandCount() < 1 )
113 {
114 return nullptr;
115 }
116
117
118 QgsRasterRenderer *renderer = nullptr;
119 switch ( drawingStyle )
120 {
122 {
123 const int grayBand = 1; //reasonable default
125 renderer = new QgsPalettedRasterRenderer( provider,
126 grayBand,
127 classes );
128 }
129 break;
132 {
133 const int grayBand = 1;
134 renderer = new QgsSingleBandGrayRenderer( provider, grayBand );
135
137 provider->dataType( grayBand ) ) );
138
139// Default contrast enhancement is set from QgsRasterLayer, it has already setContrastEnhancementAlgorithm(). Default enhancement must only be set if default style was not loaded (to avoid stats calculation).
140 ( ( QgsSingleBandGrayRenderer * )renderer )->setContrastEnhancement( ce );
141 break;
142 }
144 {
145 const int bandNo = 1;
146 double minValue = 0;
147 double maxValue = 0;
148 // TODO: avoid calculating statistics if not necessary (default style loaded)
149 minMaxValuesForBand( bandNo, provider, minValue, maxValue );
150 QgsRasterShader *shader = new QgsRasterShader( minValue, maxValue );
151 renderer = new QgsSingleBandPseudoColorRenderer( provider, bandNo, shader );
152 break;
153 }
155 {
156 const QgsSettings s;
157
158 int redBand = s.value( QStringLiteral( "/Raster/defaultRedBand" ), 1 ).toInt();
159 if ( redBand < 0 || redBand > provider->bandCount() )
160 {
161 redBand = -1;
162 }
163 int greenBand = s.value( QStringLiteral( "/Raster/defaultGreenBand" ), 2 ).toInt();
164 if ( greenBand < 0 || greenBand > provider->bandCount() )
165 {
166 greenBand = -1;
167 }
168 int blueBand = s.value( QStringLiteral( "/Raster/defaultBlueBand" ), 3 ).toInt();
169 if ( blueBand < 0 || blueBand > provider->bandCount() )
170 {
171 blueBand = -1;
172 }
173
174 renderer = new QgsMultiBandColorRenderer( provider, redBand, greenBand, blueBand );
175 break;
176 }
178 {
179 renderer = new QgsSingleBandColorDataRenderer( provider, 1 );
180 break;
181 }
182 default:
183 return nullptr;
184 }
185
186 QgsRasterTransparency *tr = new QgsRasterTransparency(); //renderer takes ownership
187 const int bandCount = renderer->usesBands().size();
188 if ( bandCount == 1 )
189 {
190 const QList<QgsRasterTransparency::TransparentSingleValuePixel> transparentSingleList;
191 tr->setTransparentSingleValuePixelList( transparentSingleList );
192 }
193 else if ( bandCount == 3 )
194 {
195 const QList<QgsRasterTransparency::TransparentThreeValuePixel> transparentThreeValueList;
196 tr->setTransparentThreeValuePixelList( transparentThreeValueList );
197 }
198 renderer->setRasterTransparency( tr );
199 return renderer;
200}
201
202bool QgsRasterRendererRegistry::minMaxValuesForBand( int band, QgsRasterDataProvider *provider, double &minValue, double &maxValue ) const
203{
204 if ( !provider )
205 {
206 return false;
207 }
208
209 minValue = 0;
210 maxValue = 0;
211
212 const QgsSettings s;
213 if ( s.value( QStringLiteral( "/Raster/useStandardDeviation" ), false ).toBool() )
214 {
216
217 const double stdDevFactor = s.value( QStringLiteral( "/Raster/defaultStandardDeviation" ), 2.0 ).toDouble();
218 const double diff = stdDevFactor * stats.stdDev;
219 minValue = stats.mean - diff;
220 maxValue = stats.mean + diff;
221 }
222 else
223 {
225 minValue = stats.minimumValue;
226 maxValue = stats.maximumValue;
227 }
228 return true;
229}
DataType
Raster data types.
Definition: qgis.h:129
static QIcon getThemeIcon(const QString &name, const QColor &fillColor=QColor(), const QColor &strokeColor=QColor())
Helper to get a theme icon.
Manipulates raster or point cloud pixel values so that they enhanceContrast or clip into a specified ...
static QgsRasterRenderer * create(const QDomElement &elem, QgsRasterInterface *input)
Factory method to create a new renderer.
Renderer for multiband images with the color components.
static QgsRasterRenderer * create(const QDomElement &elem, QgsRasterInterface *input)
Renderer for paletted raster images.
QList< QgsPalettedRasterRenderer::Class > ClassData
Map of value to class properties.
static QgsRasterRenderer * create(const QDomElement &elem, QgsRasterInterface *input)
static QgsPalettedRasterRenderer::ClassData colorTableToClassData(const QList< QgsColorRampShader::ColorRampItem > &table)
Converts a raster color table to paletted renderer class data.
The RasterBandStats struct is a container for statistics about a single raster band.
double mean
The mean cell value for the band. NO_DATA values are excluded.
double stdDev
The standard deviation of the cell values.
double minimumValue
The minimum cell value in the raster band.
double maximumValue
The maximum cell value in the raster band.
static QgsRasterRenderer * create(const QDomElement &elem, QgsRasterInterface *input)
Creates an instance of the renderer based on definition from XML (used by renderer registry)
Base class for raster data providers.
Qgis::DataType dataType(int bandNo) const override=0
Returns data type for the band specified by number.
virtual QList< QgsColorRampShader::ColorRampItem > colorTable(int bandNo) const
virtual int bandCount() const =0
Gets number of bands.
virtual QgsRasterBandStats bandStatistics(int bandNo, int stats=QgsRasterBandStats::All, const QgsRectangle &extent=QgsRectangle(), int sampleSize=0, QgsRasterBlockFeedback *feedback=nullptr)
Returns the band statistics.
void insertWidgetFunction(const QString &rendererName, QgsRasterRendererWidgetCreateFunc func)
QgsRasterRenderer * defaultRendererForDrawingStyle(QgsRaster::DrawingStyle drawingStyle, QgsRasterDataProvider *provider) const
Creates a default renderer for a raster drawing style (considering user options such as default contr...
QList< QgsRasterRendererRegistryEntry > entries() const
void insert(const QgsRasterRendererRegistryEntry &entry)
bool rendererData(const QString &rendererName, QgsRasterRendererRegistryEntry &data) const
Raster renderer pipe that applies colors to a raster.
virtual QList< int > usesBands() const
Returns a list of band numbers used by the renderer.
void setRasterTransparency(QgsRasterTransparency *t)
Interface for all raster shaders.
Defines the list of pixel values to be considered as transparent or semi transparent when rendering r...
void setTransparentSingleValuePixelList(const QList< QgsRasterTransparency::TransparentSingleValuePixel > &newList)
Sets the transparent single value pixel list, replacing the whole existing list.
void setTransparentThreeValuePixelList(const QList< QgsRasterTransparency::TransparentThreeValuePixel > &newList)
Sets the transparent three value pixel list, replacing the whole existing list.
DrawingStyle
This enumerator describes the different kinds of drawing we can do.
Definition: qgsraster.h:90
@ SingleBandColorDataStyle
Definition: qgsraster.h:101
@ MultiBandColor
Definition: qgsraster.h:100
@ PalettedColor
Definition: qgsraster.h:94
@ SingleBandPseudoColor
Definition: qgsraster.h:93
@ SingleBandGray
Definition: qgsraster.h:92
@ MultiBandSingleBandGray
Definition: qgsraster.h:98
This class is a composition of two QSettings instances:
Definition: qgssettings.h:62
QVariant value(const QString &key, const QVariant &defaultValue=QVariant(), Section section=NoSection) const
Returns the value for setting key.
Raster renderer pipe for single band color.
static QgsRasterRenderer * create(const QDomElement &elem, QgsRasterInterface *input)
Raster renderer pipe for single band gray.
static QgsRasterRenderer * create(const QDomElement &elem, QgsRasterInterface *input)
Raster renderer pipe for single band pseudocolor.
static QgsRasterRenderer * create(const QDomElement &elem, QgsRasterInterface *input)
QgsRasterRendererWidget *(* QgsRasterRendererWidgetCreateFunc)(QgsRasterLayer *, const QgsRectangle &extent)
QgsRasterRenderer *(* QgsRasterRendererCreateFunc)(const QDomElement &, QgsRasterInterface *input)
Registry for raster renderer entries.
QgsRasterRendererRegistryEntry()=default
Constructor for QgsRasterRendererRegistryEntry.