Quantum GIS API Documentation  1.7.4
src/core/raster/qgscolorrampshader.h
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00001 /* **************************************************************************
00002                 qgscolorrampshader.h -  description
00003                        -------------------
00004 begin                : Fri Dec 28 2007
00005 copyright            : (C) 2007 by Peter J. Ersts
00006 email                : [email protected]
00007 
00008 This class is based off of code that was originally written by Marco Hugentobler and
00009 originally part of the larger QgsRasterLayer class
00010 ****************************************************************************/
00011 
00012 /* **************************************************************************
00013  *                                                                         *
00014  *   This program is free software; you can redistribute it and/or modify  *
00015  *   it under the terms of the GNU General Public License as published by  *
00016  *   the Free Software Foundation; either version 2 of the License, or     *
00017  *   (at your option) any later version.                                   *
00018  *                                                                         *
00019  ***************************************************************************/
00020 
00021 #ifndef QGSCOLORRAMPSHADER_H
00022 #define QGSCOLORRAMPSHADER_H
00023 
00024 #include <QColor>
00025 #include <QMap>
00026 
00027 #include "qgsrastershaderfunction.h"
00028 
00032 class CORE_EXPORT QgsColorRampShader : public QgsRasterShaderFunction
00033 {
00034 
00035   public:
00036     QgsColorRampShader( double theMinimumValue = 0.0, double theMaximumValue = 255.0 );
00037 
00038     //An entry for classification based upon value.
00039     //Such a classification is typically used for
00040     //single band layers where a pixel value represents
00041     //not a color but a quantity, e.g. temperature or elevation
00042     struct ColorRampItem
00043     {
00045       ColorRampItem() {}
00047       ColorRampItem( double val, QColor col, QString lbl = QString() ) : label( lbl ), value( val ), color( col ) {}
00048 
00049       QString label;
00050       double value;
00051       QColor color;
00052 
00053       // compare operator for sorting
00054       bool operator<( const ColorRampItem& other ) const { return value < other.value; }
00055     };
00056 
00057     enum ColorRamp_TYPE
00058     {
00059       INTERPOLATED,
00060       DISCRETE,
00061       EXACT
00062     };
00063 
00065     QList<QgsColorRampShader::ColorRampItem> colorRampItemList() const {return mColorRampItemList;}
00066 
00068     QgsColorRampShader::ColorRamp_TYPE colorRampType() {return mColorRampType;}
00069 
00071     QString colorRampTypeAsQString();
00072 
00074     int maximumColorCacheSize() { return mMaximumColorCacheSize; }
00075 
00077     void setColorRampItemList( const QList<QgsColorRampShader::ColorRampItem>& theList ); //TODO: sort on set
00078 
00080     void setColorRampType( QgsColorRampShader::ColorRamp_TYPE theColorRampType );
00081 
00083     void setColorRampType( QString );
00084 
00086     void setMaximumColorCacheSize( int theSize ) { mMaximumColorCacheSize = theSize; }
00087 
00089     bool shade( double, int*, int*, int* );
00090 
00092     bool shade( double, double, double, int*, int*, int* );
00093 
00094   private:
00096     int mCurrentColorRampItemIndex;
00097 
00098     //TODO: Consider pulling this out as a separate class and internally storing as a QMap rather than a QList
00100     QList<QgsColorRampShader::ColorRampItem> mColorRampItemList;
00101 
00103     QgsColorRampShader::ColorRamp_TYPE mColorRampType;
00104 
00106     QMap<double, QColor> mColorCache;
00107 
00109     int mMaximumColorCacheSize;
00110 
00111 
00112 
00114     bool discreteColor( double, int*, int*, int* );
00115 
00117     bool exactColor( double, int*, int*, int* );
00118 
00120     bool interpolatedColor( double, int*, int*, int* );
00121 };
00122 
00123 #endif
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