Projections.h

Go to the documentation of this file.

//
// Projections.h
//
// Copyright (c) 2001-2007 Virtual Terrain Project
// Free for all uses, see license.txt for details.
//
// Derived from public-domain USGS software.
//
#ifndef PROJECTIONSH
#define PROJECTIONSH

//
// Earth's diameter: 12756 km
// approximate circumference: 40074 km
// each degree of latitude: 111.3 km
//
#define EARTH_RADIUS        6378000.0f  // in meters
#define METERS_PER_LATITUDE 111317.1f

// Some class names are just too long!
#define OCT OGRCoordinateTransformation

// Do not change the order of this enumeration
enum LinearUnits
{
    LU_DEGREES,
    LU_METERS,
    LU_FEET_INT,    // International Foot
    LU_FEET_US,     // U.S. Survey Foot
    LU_UNITEDGE,    // Unit Edges: Dymaxion Projection
    LU_UNKNOWN
};

// Define a few common datums for convenience
#define EPSG_DATUM_OLD_HAWAIIAN 6135
#define EPSG_DATUM_PUERTO_RICO  6139
#define EPSG_DATUM_NAD27        6267
#define EPSG_DATUM_NAD83        6269
#define EPSG_DATUM_WGS72        6322
#define EPSG_DATUM_WGS84        6326

#include "ogr_spatialref.h"
#include "MathTypes.h"


class vtProjection : public OGRSpatialReference
{
public:
    vtProjection();
    ~vtProjection();

    // Assignment
    vtProjection &operator=(const vtProjection &ref);

    // Equality
    bool operator==(const vtProjection &ref) const;
    bool operator!=(const vtProjection &ref) const;

    void    SetUTMZone(int iZone);
    int     GetUTMZone() const;
    OGRErr  SetDatum(int iDatum);
    int     GetDatum() const;
    LinearUnits GetUnits() const;
    int     GuessEPSGCode() const;

    OGRErr  SetGeogCSFromDatum(int iDatum);

    bool    SetProjectionSimple(bool bUTM, int iUTMZone, int iDatum);
    void    SetSpatialReference(OGRSpatialReference *pRef);

    const char *GetProjectionName() const;
    const char *GetProjectionNameShort() const;

    bool GetTextDescription(char *type, char *value) const;
    bool SetTextDescription(const char *type, const char *value);

    bool ReadProjFile(const char *filename);
    bool WriteProjFile(const char *filename) const;

    static double GeodesicDistance(const DPoint2 &in, const DPoint2 &out, bool bQuick = false);

    void SetDymaxion(bool bTrue) { m_bDymaxion = bTrue; }
    bool IsDymaxion() const { return m_bDymaxion; }

protected:
    bool    m_bDymaxion;

    // Useful for debugging
    void LogDescription() const;
};

struct StatePlaneInfo
{
    const char *name;
    bool bNAD27;
    bool bNAD83;
    int usgs_code;
};

class Geodesic
{
public:
    void CalculateInverse();

    double  a;
    double  lam1, phi1;
    double  lam2, phi2;
    double  S;
    double  onef, f, f2, f4, f64;
};


// Helper functions

const char *DatumToString(int d);
const char *DatumToStringShort(int d);
struct EPSGDatum
{
    bool bCommon;
    int iCode;
    const char *szName;
    const char *szShortName;
};
extern vtArray<EPSGDatum> g_EPSGDatums;
void SetupEPSGDatums();

StatePlaneInfo *GetStatePlaneTable();
int GetNumStatePlanes();
void CreateSimilarGeographicProjection(const vtProjection &source, vtProjection &geo);
OCT *CreateConversionIgnoringDatum(const vtProjection *pSource, vtProjection *pTarget);
OCT *CreateCoordTransform(const vtProjection *pSource,
                          const vtProjection *pTarget, bool bLog = false);

double EstimateDegreesToMeters(double latitude);

double GetMetersPerUnit(LinearUnits lu);

const char *GetLinearUnitName(LinearUnits lu);

double MetersPerLongitude(double latitude);

bool ReadAssociatedWorldFile(const char *filename_base, double params[6]);


// Stick this here for now, although it really belongs in its own module

class GDALInitResult
{
public:
    GDALInitResult() { hasGDAL_DATA = false; hasPROJ_LIB = false; hasPROJSO = false; }

    bool hasGDAL_DATA;
    bool hasPROJ_LIB;
    bool hasPROJSO;

    bool Success() { return hasGDAL_DATA && hasPROJ_LIB && hasPROJSO; }
};

class GDALWrapper
{
public:
    GDALWrapper();
    ~GDALWrapper();

    void RequestGDALFormats();
    void RequestOGRFormats();
    bool Init();
    GDALInitResult* GetInitResult() { return &m_initResult; }
    bool TestPROJ4();

protected:
    bool FindGDALData();
    bool FindPROJ4Data();
    bool FindPROJ4SO();

    bool m_bGDALFormatsRegistered;
    bool m_bOGRFormatsRegistered;
    GDALInitResult m_initResult;
};

extern GDALWrapper g_GDALWrapper;

#ifdef WIN32
    #define DEFAULT_LOCATION_GDAL_DATA "../../GDAL-data/"
    #define DEFAULT_LOCATION_PROJ_LIB "../../PROJ4-data/"
#elif __APPLE__
    #define DEFAULT_LOCATION_GDAL_DATA "Shared/share/gdal/"
    #define DEFAULT_LOCATION_PROJ_LIB "Shared/share/proj/"
    #define DEFAULT_LOCATION_PROJSO "Shared/lib/"
#else // other unixes
    #define DEFAULT_LOCATION_GDAL_DATA "/usr/local/share/gdal/"
    #define DEFAULT_LOCATION_PROJ_LIB "/usr/local/share/proj/"
#  if _LP64
#       define DEFAULT_LOCATION_PROJSO "/usr/local/lib64/"
#  else
#       define DEFAULT_LOCATION_PROJSO "/usr/local/lib/"
#  endif
#endif

#endif  // PROJECTIONSH