qgsmaptopixel.h

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/***************************************************************************
                          qgsmaptopixel.h  -  description
                             -------------------
    begin                : Sat Jun 22 2002
    copyright            : (C) 2002 by Gary E.Sherman
    email                : sherman at mrcc.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 QGSMAPTOPIXEL
#define QGSMAPTOPIXEL
 
#include <cassert>
 
#include "qgis.h"
#include "qgis_core.h"
#include "qgis_sip.h"
#include "qgspointxy.h"
 
#include <QTransform>
 
class QPoint;

class CORE_EXPORT QgsMapToPixel
{
  public:
    QgsMapToPixel();

    QgsMapToPixel( double mapUnitsPerPixel, double centerX, double centerY, int widthPixels, int heightPixels, double rotation );

    QgsMapToPixel( double mapUnitsPerPixel );

    static QgsMapToPixel fromScale( double scale, Qgis::DistanceUnit mapUnits, double dpi = 96 );

    bool isValid() const { return mValid; }

    QgsPointXY transform( const QgsPointXY &p ) const
    {
      qreal x = p.x();
      qreal y = p.y();
      transformInPlace( x, y );
      return QgsPointXY( x, y );
    }

    void transform( QgsPointXY *p ) const
    {
      qreal x = p->x();
      qreal y = p->y();
      transformInPlace( x, y );
      p->set( x, y );
    }

    QgsPointXY transform( qreal x, qreal y ) const
    {
      transformInPlace( x, y );
      return QgsPointXY( x, y );
    }

    void transformInPlace( double &x, double &y ) const
    {
      qreal mx, my;
      mMatrix.map( static_cast< qreal >( x ), static_cast< qreal >( y ), &mx, &my );
      x = mx;
      y = my;
    }

    QRectF transformBounds( const QRectF &bounds ) const
    {
      QPointF topLeft = bounds.topLeft();
      QPointF topRight = bounds.topRight();
      QPointF bottomLeft = bounds.bottomLeft();
      QPointF bottomRight = bounds.bottomRight();
 
      transformInPlace( topLeft.rx(), topLeft.ry() );
      transformInPlace( topRight.rx(), topRight.ry() );
      transformInPlace( bottomLeft.rx(), bottomLeft.ry() );
      transformInPlace( bottomRight.rx(), bottomRight.ry() );
 
      auto minMaxX = std::minmax( { topLeft.x(), topRight.x(), bottomLeft.x(), bottomRight.x() } );
      auto minMaxY = std::minmax( { topLeft.y(), topRight.y(), bottomLeft.y(), bottomRight.y() } );
 
      const double left = minMaxX.first;
      const double right = minMaxX.second;
      const double top = minMaxY.first;
      const double bottom = minMaxY.second;
      return QRectF( left, top, right - left, bottom - top );
    }

    void transformInPlace( float &x, float &y ) const SIP_SKIP
    {
      double mx = x, my = y;
      transformInPlace( mx, my );
      x = mx;
      y = my;
    }
 
#ifndef SIP_RUN

    template<class T> SIP_SKIP void transformInPlace( QVector<T> &x, QVector<T> &y ) const
    {
      assert( x.size() == y.size() );
      T *xData = x.data();
      T *yData = y.data();
      const auto size = x.size();
      for ( int i = 0; i < size; ++i )
        transformInPlace( *xData++, *yData++ );
    }
#endif

    QgsPointXY toMapCoordinates( int x, int y ) const { return toMapCoordinates( static_cast<double>( x ), static_cast<double>( y ) ); }

    QgsPointXY toMapCoordinates( double x, double y ) const SIP_PYNAME( toMapCoordinatesF )
    {
      bool invertible;
      const QTransform matrix = mMatrix.inverted( &invertible );
      assert( invertible );
      qreal mx, my;
      matrix.map( static_cast< qreal >( x ), static_cast< qreal >( y ), &mx, &my );
      return QgsPointXY( mx, my );
    }

    QgsPointXY toMapCoordinates( QPoint p ) const
    {
      const QgsPointXY mapPt = toMapCoordinates( static_cast<double>( p.x() ), static_cast<double>( p.y() ) );
      return QgsPointXY( mapPt );
    }

    Q_DECL_DEPRECATED QgsPointXY toMapPoint( double x, double y ) const SIP_DEPRECATED { return toMapCoordinates( x, y ); }

    void setMapUnitsPerPixel( double mapUnitsPerPixel );

    double mapUnitsPerPixel() const { return mMapUnitsPerPixel; }

    int mapWidth() const { return mWidth; }

    int mapHeight() const { return mHeight; }

    void setMapRotation( double degrees, double cx, double cy );

    double mapRotation() const { return mRotation; }

    void setParameters( double mapUnitsPerPixel, double centerX, double centerY, int widthPixels, int heightPixels, double rotation );

    void setParameters( double mapUnitsPerPixel, double centerX, double centerY, int widthPixels, int heightPixels, double rotation, bool *ok ) SIP_SKIP;

    QString showParameters() const;

    QTransform transform() const;

    double xCenter() const { return mXCenter; }

    double yCenter() const { return mYCenter; }
 
    bool operator==( const QgsMapToPixel &other ) const
    {
      return mValid == other.mValid
             && mMapUnitsPerPixel == other.mMapUnitsPerPixel
             && mWidth == other.mWidth
             && mHeight == other.mHeight
             && mRotation == other.mRotation
             && mXCenter == other.mXCenter
             && mYCenter == other.mYCenter
             && mXMin == other.mXMin
             && mYMin == other.mYMin;
    }
 
    bool operator!=( const QgsMapToPixel &other ) const { return !( *this == other ); }
 
  private:
    bool mValid = false;
    double mMapUnitsPerPixel = 1;
    int mWidth = 1;
    int mHeight = 1;
    double mRotation = 0.0;
    double mXCenter = 0.5;
    double mYCenter = 0.5;
    double mXMin = 0;
    double mYMin = 0;
    QTransform mMatrix;
 
    bool updateMatrix();
};
 
 
#endif // QGSMAPTOPIXEL