qgsrasterlayerutils.h

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/***************************************************************************
                          qgsrasterlayerutils.h
                          -------------------------
    begin                : March 2024
    copyright            : (C) 2024 by Nyall Dawson
    email                : nyall dot dawson at gmail dot com
 ***************************************************************************/
 
/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
 
#ifndef QGSRASTERLAYERUTILS_H
#define QGSRASTERLAYERUTILS_H
 
#include "qgis.h"
#include "qgis_core.h"
#include "qgis_sip.h"
#include "qgspointxy.h"
#include "qgsrange.h"
 
#include <QColor>
#include <QString>
 
using namespace Qt::StringLiterals;
 
class QgsRasterLayer;
class QgsRasterDataProvider;
class QgsRasterMinMaxOrigin;
class QgsRectangle;

class CORE_EXPORT QgsRasterReliefColor
{
  public:
    QgsRasterReliefColor( const QColor &c, double min, double max )
      : color( c )
      , minElevation( min )
      , maxElevation( max )
    {}

    QColor color;
    double minElevation = 0;
    double maxElevation = 0;
 
    bool operator==( const QgsRasterReliefColor &other ) const
    {
      return qgsDoubleNear( minElevation, other.minElevation ) && qgsDoubleNear( maxElevation, other.maxElevation ) && color == other.color;
    }
 
    bool operator!=( const QgsRasterReliefColor &other ) const { return !( *this == other ); }
 
#ifdef SIP_RUN
    // clang-format off
    SIP_PYOBJECT __repr__();
    % MethodCode
    QString str = u"<QgsRasterReliefColor: %1-%2 (%3)>"_s.arg( qgsDoubleToString( sipCpp->minElevation ), qgsDoubleToString( sipCpp->maxElevation ), sipCpp->color.name() );
    sipRes = PyUnicode_FromString( str.toUtf8().constData() );
    % End
// clang-format on
#endif
};

class CORE_EXPORT QgsRasterLayerUtils
{
  public:
    static int renderedBandForElevationAndTemporalRange( QgsRasterLayer *layer, const QgsDateTimeRange &temporalRange, const QgsDoubleRange &elevationRange, bool &matched SIP_OUT );

    static void computeMinMax(
      QgsRasterDataProvider *provider, int band, const QgsRasterMinMaxOrigin &mmo, Qgis::RasterRangeLimit limits, const QgsRectangle &extent, int sampleSize, double &min SIP_OUT, double &max SIP_OUT
    );

    static QgsRectangle alignRasterExtent( const QgsRectangle &extent, const QgsPointXY &origin, double pixelSizeX, double pixelSizeY );

    static QList<QgsRasterReliefColor> calculateOptimizedReliefClasses( QgsRasterDataProvider *provider, int band );
 
  private:
    static int frequencyClassForElevation( double elevation, double minElevation, double elevationClassRange );

    static void optimiseClassBreaks( QList<int> &breaks, double *frequencies );

    static bool calculateRegression( const QList<QPair<int, double>> &input, double &a, double &b );
};
 
#endif //QGSRASTERLAYERUTILS_H