qgis.h

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/***************************************************************************
                          qgis.h - QGIS namespace
                             -------------------
    begin                : Sat Jun 30 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 QGIS_H
#define QGIS_H

#include <QEvent>
#include <QString>
#include <QRegExp>
#include <QMetaType>
#include <QVariant>
#include <QDateTime>
#include <QDate>
#include <QTime>
#include <QHash>
#include <stdlib.h>
#include <cfloat>
#include <cmath>
#include <qnumeric.h>

#include <qgswkbtypes.h>

class CORE_EXPORT QGis
{
  public:
    // Version constants
    //
    // Version string
    static QString QGIS_VERSION;
    // Version number used for comparing versions using the "Check QGIS Version" function
    static const int QGIS_VERSION_INT;
    // Release name
    static QString QGIS_RELEASE_NAME;
    // The development version
    static const char* QGIS_DEV_VERSION;

    // Enumerations
    //

    // Feature types
    // @deprecated use QgsWKBTypes::Type
    /* Q_DECL_DEPRECATED */
    enum WkbType
    {
      WKBUnknown = 0,
      WKBPoint = 1,
      WKBLineString,
      WKBPolygon,
      WKBMultiPoint,
      WKBMultiLineString,
      WKBMultiPolygon,
      WKBNoGeometry = 100, //attributes only
      WKBPoint25D = 0x80000001,
      WKBLineString25D,
      WKBPolygon25D,
      WKBMultiPoint25D,
      WKBMultiLineString25D,
      WKBMultiPolygon25D,
    };

    // @deprecated use QgsWKBTypes::singleType
    /* Q_DECL_DEPRECATED */
    static WkbType singleType( WkbType type );

    // @deprecated use QgsWKBTypes::multiType
    /* Q_DECL_DEPRECATED */
    static WkbType multiType( WkbType type );

    // @deprecated use QgsWKBTypes::flatType
    /* Q_DECL_DEPRECATED */
    static WkbType flatType( WkbType type );

    // @deprecated use QgsWKBTypes::isSingleType
    /* Q_DECL_DEPRECATED */
    static bool isSingleType( WkbType type );

    // @deprecated use QgsWKBTypes::isMultiType
    /* Q_DECL_DEPRECATED */
    static bool isMultiType( WkbType type );

    // get dimension of points
    // @deprecated use QgsWKBTypes::coordDimensions()
    /* Q_DECL_DEPRECATED */
    static int wkbDimensions( WkbType type );

    static QgsWKBTypes::Type fromOldWkbType( QGis::WkbType type );

    static QGis::WkbType fromNewWkbType( QgsWKBTypes::Type type );

    enum GeometryType
    {
      Point,
      Line,
      Polygon,
      UnknownGeometry,
      NoGeometry
    };

    static const char *vectorGeometryType( GeometryType type );

    static const char *featureType( WkbType type );

    enum DataType
    {                UnknownDataType = 0,        Byte = 1,     UInt16 = 2,        Int16 = 3,  UInt32 = 4,     Int32 = 5,      Float32 = 6,     Float64 = 7,                              CInt16 = 8,                              CInt32 = 9,                            CFloat32 = 10,                            CFloat64 = 11,                      ARGB32 = 12,        ARGB32_Premultiplied = 13
    };


    //TODO QGIS 3.0 - clean up and move to QgsUnitTypes and rename to DistanceUnit
    enum UnitType
    {
      Meters = 0, 
      Feet = 1, 
      Degrees = 2,  //for 1.0 api backwards compatibility
      NauticalMiles = 7, 
      Kilometers = 8, 
      Yards = 9, 
      Miles = 10, 
      UnknownUnit = 3, 
      // for [1.4;1.8] api compatibility
      DecimalDegrees = 2,         // was 2
      DegreesMinutesSeconds = 2,  // was 4
      DegreesDecimalMinutes = 2,  // was 5
    };

    Q_DECL_DEPRECATED static QString toLiteral( QGis::UnitType unit );

    Q_DECL_DEPRECATED static UnitType fromLiteral( const QString& literal, QGis::UnitType defaultType = UnknownUnit );

    Q_DECL_DEPRECATED static QString tr( QGis::UnitType unit );

    Q_DECL_DEPRECATED static UnitType fromTr( const QString& literal, QGis::UnitType defaultType = UnknownUnit );

    Q_DECL_DEPRECATED static double fromUnitToUnitFactor( QGis::UnitType fromUnit, QGis::UnitType toUnit );

    static double permissiveToDouble( QString string, bool& ok );

    static int permissiveToInt( QString string, bool& ok );

    enum UserEvent
    {
      // These first two are useful for threads to alert their parent data providers

      ProviderExtentCalcEvent = ( QEvent::User + 1 ),

      ProviderCountCalcEvent
    };

    Q_DECL_DEPRECATED static const double DEFAULT_IDENTIFY_RADIUS;

    static const double DEFAULT_SEARCH_RADIUS_MM;

    static const float DEFAULT_MAPTOPIXEL_THRESHOLD;

    static const QColor DEFAULT_HIGHLIGHT_COLOR;

    static double DEFAULT_HIGHLIGHT_BUFFER_MM;

    static double DEFAULT_HIGHLIGHT_MIN_WIDTH_MM;

    static double SCALE_PRECISION;

  private:
    // String representation of unit types (set in qgis.cpp)
    static const char *qgisUnitTypes[];

};

// hack to workaround warnings when casting void pointers
// retrieved from QLibrary::resolve to function pointers.
// It's assumed that this works on all systems supporting
// QLibrary
#if QT_VERSION >= 0x050000
#define cast_to_fptr(f) f
#else
inline void ( *cast_to_fptr( void *p ) )()
{
  union
  {
    void *p;
    void ( *f )();
  } u;

  u.p = p;
  return u.f;
}
#endif

// based on Boojum's code from http://stackoverflow.com/questions/3556687/prevent-firing-signals-in-qt
template<class Object> class QgsSignalBlocker
{
  public:

    explicit QgsSignalBlocker( Object* object )
        : mObject( object )
        , mPreviousState( object->blockSignals( true ) )
    {}

    ~QgsSignalBlocker()
    {
      mObject->blockSignals( mPreviousState );
    }

    Object* operator->() { return mObject; }

  private:

    Object* mObject;
    bool mPreviousState;

};

// based on Boojum's code from http://stackoverflow.com/questions/3556687/prevent-firing-signals-in-qt
template<class Object> inline QgsSignalBlocker<Object> whileBlocking( Object* object )
{
  return QgsSignalBlocker<Object>( object );
}

inline QString qgsDoubleToString( double a, int precision = 17 )
{
  if ( precision )
    return QString::number( a, 'f', precision ).remove( QRegExp( "\\.?0+$" ) );
  else
    return QString::number( a, 'f', precision );
}

inline bool qgsDoubleNear( double a, double b, double epsilon = 4 * DBL_EPSILON )
{
  const double diff = a - b;
  return diff > -epsilon && diff <= epsilon;
}

inline bool qgsFloatNear( float a, float b, float epsilon = 4 * FLT_EPSILON )
{
  const float diff = a - b;
  return diff > -epsilon && diff <= epsilon;
}

inline bool qgsDoubleNearSig( double a, double b, int significantDigits = 10 )
{
  // The most simple would be to print numbers as %.xe and compare as strings
  // but that is probably too costly
  // Then the fastest would be to set some bits directly, but little/big endian
  // has to be considered (maybe TODO)
  // Is there a better way?
  int aexp, bexp;
  double ar = frexp( a, &aexp );
  double br = frexp( b, &bexp );

  return aexp == bexp &&
         qRound( ar * pow( 10.0, significantDigits ) ) == qRound( br * pow( 10.0, significantDigits ) );
}

inline double qgsRound( double x )
{
  return x < 0.0 ? std::ceil( x - 0.5 ) : std::floor( x + 0.5 );
}

// Add missing qHash implementation for QDate, QTime, QDateTime
// implementations taken from upstream Qt5 versions
#if QT_VERSION < 0x050000

inline uint qHash( const QDateTime &key )
{
  return qHash( key.toMSecsSinceEpoch() );
}

inline uint qHash( const QDate &key )
{
  return qHash( key.toJulianDay() );
}

inline uint qHash( const QTime &key )
{
  return QTime( 0, 0, 0, 0 ).msecsTo( key );
}
#endif

CORE_EXPORT bool qgsVariantLessThan( const QVariant& lhs, const QVariant& rhs );

CORE_EXPORT bool qgsVariantGreaterThan( const QVariant& lhs, const QVariant& rhs );

CORE_EXPORT QString qgsVsiPrefix( const QString& path );

void CORE_EXPORT *qgsMalloc( size_t size );

void CORE_EXPORT *qgsCalloc( size_t nmemb, size_t size );

void CORE_EXPORT qgsFree( void *ptr );

extern CORE_EXPORT const QString GEOWKT;
extern CORE_EXPORT const QString PROJECT_SCALES;

extern CORE_EXPORT const QString GEOPROJ4;
const long GEOSRID = 4326;
const long GEOCRS_ID = 3452;
const long GEO_EPSG_CRS_ID = 4326;
extern CORE_EXPORT const QString GEO_EPSG_CRS_AUTHID;
const int PROJ_PREFIX_LEN = 6;
const int ELLPS_PREFIX_LEN = 7;
const int LAT_PREFIX_LEN = 7;
const int USER_CRS_START_ID = 100000;

extern CORE_EXPORT const QString GEO_NONE;

//
// Constants for point symbols
//

const double MINIMUM_POINT_SIZE = 0.1;
const double DEFAULT_POINT_SIZE = 2.0;
const double DEFAULT_LINE_WIDTH = 0.26;

const double DEFAULT_SEGMENT_EPSILON = 1e-8;

typedef QMap<QString, QString> QgsStringMap;

typedef unsigned long long qgssize;

#if (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)) || defined(__clang__)
#define Q_NOWARN_DEPRECATED_PUSH \
  _Pragma("GCC diagnostic push") \
  _Pragma("GCC diagnostic ignored \"-Wdeprecated-declarations\"");
#define Q_NOWARN_DEPRECATED_POP \
  _Pragma("GCC diagnostic pop");
#elif defined(_MSC_VER)
#define Q_NOWARN_DEPRECATED_PUSH \
  __pragma(warning(push)) \
  __pragma(warning(disable:4996))
#define Q_NOWARN_DEPRECATED_POP \
  __pragma(warning(pop))
#else
#define Q_NOWARN_DEPRECATED_PUSH
#define Q_NOWARN_DEPRECATED_POP
#endif

#ifndef QGISEXTERN
#ifdef Q_OS_WIN
#  define QGISEXTERN extern "C" __declspec( dllexport )
#  ifdef _MSC_VER
// do not warn about C bindings returing QString
#    pragma warning(disable:4190)
#  endif
#else
#  if defined(__GNUC__) || defined(__clang__)
#    define QGISEXTERN extern "C" __attribute__ ((visibility ("default")))
#  else
#    define QGISEXTERN extern "C"
#  endif
#endif
#endif
#endif

#if defined(__clang__)
#define FALLTHROUGH [[clang::fallthrough]]
#else
#define FALLTHROUGH
#endif