QGIS API Documentation 3.29.0-Master (006c3c0232)
qgscolorrampshader.h
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1/* **************************************************************************
2 qgscolorrampshader.h - description
3 -------------------
4begin : Fri Dec 28 2007
5copyright : (C) 2007 by Peter J. Ersts
7
8This class is based off of code that was originally written by Marco Hugentobler and
9originally part of the larger QgsRasterLayer class
10****************************************************************************/
11
12/* **************************************************************************
13 * *
14 * This program is free software; you can redistribute it and/or modify *
15 * it under the terms of the GNU General Public License as published by *
16 * the Free Software Foundation; either version 2 of the License, or *
17 * (at your option) any later version. *
18 * *
19 ***************************************************************************/
20
21#ifndef QGSCOLORRAMPSHADER_H
22#define QGSCOLORRAMPSHADER_H
23
24#include "qgis_core.h"
25#include "qgis_sip.h"
26#include <QColor>
27#include <QVector>
28#include <memory>
29
31#include "qgsrectangle.h"
32#include "qgsreadwritecontext.h"
34
35class QgsColorRamp;
37
43{
44
45 public:
46
48 enum Type
49 {
52 Exact
53 };
54
57 {
58 Continuous = 1,
59 EqualInterval = 2,
60 Quantile = 3
61 };
62
72 QgsColorRampShader( double minimumValue = 0.0, double maximumValue = 255.0, QgsColorRamp *colorRamp SIP_TRANSFER = nullptr, Type type = Interpolated, ClassificationMode classificationMode = Continuous );
73
75
80
84 QgsColorRampShader &operator=( const QgsColorRampShader &other );
85
86 bool operator==( const QgsColorRampShader &other ) const
87 {
88 if ( mColorRampItemList.count() != other.mColorRampItemList.count() ||
89 mClassificationMode != other.mClassificationMode ||
90 mColorRampType != other.mColorRampType )
91 {
92 return false;
93 }
94 for ( int i = 0; i < mColorRampItemList.count(); ++i )
95 {
96 if ( mColorRampItemList.at( i ) != other.mColorRampItemList.at( i ) ) return false;
97 }
98 return true;
99 }
100
101 //An entry for classification based upon value.
102 //Such a classification is typically used for
103 //single band layers where a pixel value represents
104 //not a color but a quantity, e.g. temperature or elevation
106 {
108 ColorRampItem() = default;
110 ColorRampItem( double val, const QColor &col, const QString &lbl = QString() )
111 : label( lbl )
112 , value( val )
113 , color( col )
114 {}
115
116 QString label;
117 double value = 0;
118 QColor color;
119
120 // compare operator for sorting
121 bool operator<( const QgsColorRampShader::ColorRampItem &other ) const { return value < other.value; }
122
124 {
125 return ( color != other.color ) ||
126 ( !std::isnan( value ) && !std::isnan( other.value ) && value != other.value ) ||
127 ( std::isnan( value ) != std::isnan( other.value ) );
128 }
129 };
130
132 QList<QgsColorRampShader::ColorRampItem> colorRampItemList() const { return mColorRampItemList.toList(); }
133
135 Type colorRampType() const { return mColorRampType; }
136
138 QString colorRampTypeAsQString() const;
139
141 void setColorRampItemList( const QList<QgsColorRampShader::ColorRampItem> &list ); //TODO: sort on set
142
144 void setColorRampType( QgsColorRampShader::Type colorRampType );
145
150 bool isEmpty() const;
151
157 QgsColorRamp *sourceColorRamp() const;
158
163 QgsColorRamp *createColorRamp() const SIP_FACTORY;
164
170 void setSourceColorRamp( QgsColorRamp *colorramp SIP_TRANSFER );
171
173 void setColorRampType( const QString &type );
174
182 void classifyColorRamp( int classes = 0, int band = -1, const QgsRectangle &extent = QgsRectangle(), QgsRasterInterface *input = nullptr );
183
190 void classifyColorRamp( int band = -1, const QgsRectangle &extent = QgsRectangle(), QgsRasterInterface *input = nullptr ) SIP_PYNAME( classifyColorRampV2 );
191
193 bool shade( double value, int *returnRedValue SIP_OUT, int *returnGreenValue SIP_OUT, int *returnBlueValue SIP_OUT, int *returnAlphaValue SIP_OUT ) const override;
194
196 bool shade( double redValue, double greenValue,
197 double blueValue, double alphaValue,
198 int *returnRedValue SIP_OUT, int *returnGreenValue SIP_OUT,
199 int *returnBlueValue SIP_OUT, int *returnAlphaValue SIP_OUT ) const override;
200
201 void legendSymbologyItems( QList< QPair< QString, QColor > > &symbolItems SIP_OUT ) const override;
202
207 QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context = QgsReadWriteContext() ) const;
208
213 void readXml( const QDomElement &elem, const QgsReadWriteContext &context = QgsReadWriteContext() );
214
216 void setClassificationMode( ClassificationMode classificationMode ) { mClassificationMode = classificationMode; }
217
219 ClassificationMode classificationMode() const { return mClassificationMode; }
220
226 void setClip( bool clip ) { mClip = clip; }
227
232 bool clip() const { return mClip; }
233
240 const QgsColorRampLegendNodeSettings *legendSettings() const;
241
250 void setLegendSettings( QgsColorRampLegendNodeSettings *settings SIP_TRANSFER );
251
252 protected:
253
255 std::unique_ptr<QgsColorRamp> mSourceColorRamp;
256
257 private:
258
266 QVector<QgsColorRampShader::ColorRampItem> mColorRampItemList;
267
268 Type mColorRampType;
269 ClassificationMode mClassificationMode;
270
275 mutable std::vector<int> mLUT;
276 mutable double mLUTOffset = 0.0;
277 mutable double mLUTFactor = 1.0;
278 mutable bool mLUTInitialized = false;
279
281 bool mClip = false;
282
283 std::unique_ptr< QgsColorRampLegendNodeSettings > mLegendSettings;
284
285};
286
287#endif
Settings for a color ramp legend node.
A ramp shader will color a raster pixel based on a list of values ranges in a ramp.
~QgsColorRampShader() override
ClassificationMode classificationMode() const
Returns the classification mode.
Type colorRampType() const
Returns the color ramp type.
QList< QgsColorRampShader::ColorRampItem > colorRampItemList() const
Returns the custom colormap.
bool operator==(const QgsColorRampShader &other) const
ClassificationMode
Classification modes used to create the color ramp shader.
void setClip(bool clip)
Sets whether the shader should not render values out of range.
bool clip() const
Returns whether the shader will clip values which are out of range.
Type
Supported methods for color interpolation.
@ Interpolated
Interpolates the color between two class breaks linearly.
@ Discrete
Assigns the color of the higher class for every pixel between two class breaks.
std::unique_ptr< QgsColorRamp > mSourceColorRamp
Source color ramp.
Abstract base class for color ramps.
Definition: qgscolorramp.h:30
Base class for processing filters like renderers, reprojector, resampler etc.
The raster shade function applies a shader to a pixel at render time - typically used to render grays...
The class is used as a container of context for various read/write operations on other objects.
A rectangle specified with double values.
Definition: qgsrectangle.h:42
#define SIP_PYNAME(name)
Definition: qgis_sip.h:81
#define SIP_TRANSFER
Definition: qgis_sip.h:36
#define SIP_OUT
Definition: qgis_sip.h:58
#define SIP_FACTORY
Definition: qgis_sip.h:76
ColorRampItem(double val, const QColor &col, const QString &lbl=QString())
convenience constructor
bool operator!=(const QgsColorRampShader::ColorRampItem &other) const
bool operator<(const QgsColorRampShader::ColorRampItem &other) const
ColorRampItem()=default
default constructor