#include <qgsdistancearea.h>
Public Member Functions | |
QgsDistanceArea () | |
Constructor. | |
~QgsDistanceArea () | |
Destructor. | |
void | setProjectionsEnabled (bool flag) |
sets whether coordinates must be projected to ellipsoid before measuring | |
bool | hasCrsTransformEnabled () |
returns projections enabled flag | |
void | setSourceCrs (long srsid) |
sets source spatial reference system (by QGIS CRS) | |
void | setSourceEpsgCrsId (long epsgId) |
sets source spatial reference system (by EpsgCrsId) | |
long | sourceCrs () |
returns source spatial reference system | |
bool | geographic () |
What sort of coordinate system is being used? | |
bool | setEllipsoid (const QString &ellipsoid) |
sets ellipsoid by its acronym | |
const QString & | ellipsoid () |
returns ellipsoid's acronym | |
double | ellipsoidSemiMajor () |
returns ellipsoid's semi major axis | |
double | ellipsoidSemiMinor () |
returns ellipsoid's semi minor axis | |
double | ellipsoidInverseFlattening () |
returns ellipsoid's inverse flattening | |
double | measure (QgsGeometry *geometry) |
general measurement (line distance or polygon area) | |
double | measureLine (const QList< QgsPoint > &points) |
measures line with more segments | |
double | measureLine (const QgsPoint &p1, const QgsPoint &p2) |
measures line with one segment | |
double | measurePolygon (const QList< QgsPoint > &points) |
measures polygon area | |
double | bearing (const QgsPoint &p1, const QgsPoint &p2) |
compute bearing - in radians | |
Static Public Member Functions | |
static QString | textUnit (double value, int decimals, QGis::UnitType u, bool isArea, bool keepBaseUnit=false) |
Protected Member Functions | |
unsigned char * | measureLine (unsigned char *feature, double *area, bool hasZptr=false) |
measures line distance, line points are extracted from WKB | |
unsigned char * | measurePolygon (unsigned char *feature, double *area, bool hasZptr=false) |
measures polygon area, vertices are extracted from WKB | |
double | computeDistanceBearing (const QgsPoint &p1, const QgsPoint &p2, double *course1=NULL, double *course2=NULL) |
calculates distance from two points on ellipsoid based on inverse Vincenty's formulae | |
double | computePolygonArea (const QList< QgsPoint > &points) |
calculates area of polygon on ellipsoid algorithm has been taken from GRASS: gis/area_poly1.c | |
double | computePolygonFlatArea (const QList< QgsPoint > &points) |
void | computeAreaInit () |
precalculates some values (must be called always when changing ellipsoid) | |
Private Member Functions | |
double | getQ (double x) |
double | getQbar (double x) |
Private Attributes | |
QgsCoordinateTransform * | mCoordTransform |
used for transforming coordinates from source CRS to ellipsoid's coordinates | |
bool | mProjectionsEnabled |
indicates whether we will transform coordinates | |
long | mSourceRefSys |
id of the source spatial reference system | |
QString | mEllipsoid |
ellipsoid acronym (from table tbl_ellipsoids) | |
double | mSemiMajor |
ellipsoid parameters | |
double | mSemiMinor |
double | mInvFlattening |
double | m_QA |
double | m_QB |
double | m_QC |
double | m_QbarA |
double | m_QbarB |
double | m_QbarC |
double | m_QbarD |
double | m_AE |
double | m_Qp |
double | m_E |
double | m_TwoPI |
Definition at line 35 of file qgsdistancearea.h.
QgsDistanceArea::QgsDistanceArea | ( | ) |
Constructor.
Definition at line 41 of file qgsdistancearea.cpp.
References GEOCRS_ID, mCoordTransform, mProjectionsEnabled, setEllipsoid(), and setSourceCrs().
QgsDistanceArea::~QgsDistanceArea | ( | ) |
void QgsDistanceArea::setProjectionsEnabled | ( | bool | flag | ) |
sets whether coordinates must be projected to ellipsoid before measuring
Definition at line 57 of file qgsdistancearea.cpp.
References mProjectionsEnabled.
Referenced by QgsSearchTreeNode::init(), and QgsMapRenderer::setProjectionsEnabled().
bool QgsDistanceArea::hasCrsTransformEnabled | ( | ) | [inline] |
void QgsDistanceArea::setSourceCrs | ( | long | srsid | ) |
sets source spatial reference system (by QGIS CRS)
Definition at line 62 of file qgsdistancearea.cpp.
References QgsCoordinateReferenceSystem::createFromSrsId(), mCoordTransform, and QgsCoordinateTransform::setSourceCrs().
Referenced by QgsDistanceArea(), and QgsMapRenderer::setDestinationSrs().
void QgsDistanceArea::setSourceEpsgCrsId | ( | long | epsgId | ) |
sets source spatial reference system (by EpsgCrsId)
Definition at line 69 of file qgsdistancearea.cpp.
References QgsCoordinateReferenceSystem::createFromEpsg(), mCoordTransform, and QgsCoordinateTransform::setSourceCrs().
long QgsDistanceArea::sourceCrs | ( | ) | [inline] |
bool QgsDistanceArea::geographic | ( | ) | [inline] |
bool QgsDistanceArea::setEllipsoid | ( | const QString & | ellipsoid | ) |
sets ellipsoid by its acronym
Definition at line 76 of file qgsdistancearea.cpp.
References computeAreaInit(), QgsCoordinateReferenceSystem::createFromProj4(), mCoordTransform, mEllipsoid, mInvFlattening, mSemiMajor, mSemiMinor, QgsDebugMsg, QgsCoordinateTransform::setDestCRS(), and QgsApplication::srsDbFilePath().
Referenced by QgsSearchTreeNode::init(), and QgsDistanceArea().
const QString& QgsDistanceArea::ellipsoid | ( | ) | [inline] |
double QgsDistanceArea::ellipsoidSemiMajor | ( | ) | [inline] |
double QgsDistanceArea::ellipsoidSemiMinor | ( | ) | [inline] |
double QgsDistanceArea::ellipsoidInverseFlattening | ( | ) | [inline] |
double QgsDistanceArea::measure | ( | QgsGeometry * | geometry | ) |
general measurement (line distance or polygon area)
Definition at line 175 of file qgsdistancearea.cpp.
References QgsGeometry::asWkb(), measureLine(), measurePolygon(), QgsDebugMsg, QGis::WKBLineString, QGis::WKBLineString25D, QGis::WKBMultiLineString, QGis::WKBMultiLineString25D, QGis::WKBMultiPolygon, QGis::WKBMultiPolygon25D, QGis::WKBPolygon, and QGis::WKBPolygon25D.
Referenced by QgsGeometryAnalyzer::perimeterMeasure(), QgsGeometryAnalyzer::simpleMeasure(), and QgsSearchTreeNode::valueAgainst().
double QgsDistanceArea::measureLine | ( | const QList< QgsPoint > & | points | ) |
measures line with more segments
Definition at line 273 of file qgsdistancearea.cpp.
References computeDistanceBearing(), mCoordTransform, mEllipsoid, mProjectionsEnabled, QgsCoordinateTransform::transform(), and QgsLogger::warning().
Referenced by measure(), and measureLine().
measures line with one segment
Definition at line 315 of file qgsdistancearea.cpp.
References computeDistanceBearing(), mCoordTransform, mEllipsoid, mProjectionsEnabled, QgsCoordinateTransform::transform(), QgsLogger::warning(), QgsPoint::x(), and QgsPoint::y().
double QgsDistanceArea::measurePolygon | ( | const QList< QgsPoint > & | points | ) |
measures polygon area
Definition at line 408 of file qgsdistancearea.cpp.
References computePolygonArea(), mCoordTransform, mEllipsoid, mProjectionsEnabled, QgsCoordinateTransform::transform(), and QgsLogger::warning().
Referenced by measure().
compute bearing - in radians
Definition at line 436 of file qgsdistancearea.cpp.
References computeDistanceBearing(), mCoordTransform, mEllipsoid, mProjectionsEnabled, QgsCoordinateTransform::transform(), QgsPoint::x(), and QgsPoint::y().
QString QgsDistanceArea::textUnit | ( | double | value, | |
int | decimals, | |||
QGis::UnitType | u, | |||
bool | isArea, | |||
bool | keepBaseUnit = false | |||
) | [static] |
Definition at line 671 of file qgsdistancearea.cpp.
References QGis::Degrees, QGis::Feet, QGis::Meters, QgsDebugMsg, and QGis::UnknownUnit.
unsigned char * QgsDistanceArea::measureLine | ( | unsigned char * | feature, | |
double * | area, | |||
bool | hasZptr = false | |||
) | [protected] |
measures line distance, line points are extracted from WKB
Definition at line 243 of file qgsdistancearea.cpp.
References measureLine(), and QgsDebugMsg.
unsigned char * QgsDistanceArea::measurePolygon | ( | unsigned char * | feature, | |
double * | area, | |||
bool | hasZptr = false | |||
) | [protected] |
measures polygon area, vertices are extracted from WKB
Definition at line 340 of file qgsdistancearea.cpp.
References computePolygonArea(), mCoordTransform, mEllipsoid, mProjectionsEnabled, QgsCoordinateTransform::transform(), and QgsLogger::warning().
double QgsDistanceArea::computeDistanceBearing | ( | const QgsPoint & | p1, | |
const QgsPoint & | p2, | |||
double * | course1 = NULL , |
|||
double * | course2 = NULL | |||
) | [protected] |
calculates distance from two points on ellipsoid based on inverse Vincenty's formulae
Points p1 and p2 are expected to be in degrees and in currently used ellipsoid
Definition at line 461 of file qgsdistancearea.cpp.
References DEG2RAD, M_PI, mInvFlattening, mSemiMajor, mSemiMinor, QgsPoint::x(), and QgsPoint::y().
Referenced by bearing(), and measureLine().
double QgsDistanceArea::computePolygonArea | ( | const QList< QgsPoint > & | points | ) | [protected] |
calculates area of polygon on ellipsoid algorithm has been taken from GRASS: gis/area_poly1.c
Definition at line 595 of file qgsdistancearea.cpp.
References computePolygonFlatArea(), DEG2RAD, getQ(), getQbar(), m_AE, m_E, M_PI, m_Qp, m_TwoPI, mEllipsoid, mProjectionsEnabled, and QgsDebugMsgLevel.
Referenced by measurePolygon().
double QgsDistanceArea::computePolygonFlatArea | ( | const QList< QgsPoint > & | points | ) | [protected] |
void QgsDistanceArea::computeAreaInit | ( | ) | [protected] |
precalculates some values (must be called always when changing ellipsoid)
Definition at line 567 of file qgsdistancearea.cpp.
References getQ(), m_AE, m_E, M_PI, m_QA, m_QB, m_QbarA, m_QbarB, m_QbarC, m_QbarD, m_QC, m_Qp, m_TwoPI, mSemiMajor, and mSemiMinor.
Referenced by setEllipsoid().
double QgsDistanceArea::getQ | ( | double | x | ) | [private] |
Definition at line 545 of file qgsdistancearea.cpp.
References m_QA, m_QB, and m_QC.
Referenced by computeAreaInit(), and computePolygonArea().
double QgsDistanceArea::getQbar | ( | double | x | ) | [private] |
Definition at line 556 of file qgsdistancearea.cpp.
References m_QbarA, m_QbarB, m_QbarC, and m_QbarD.
Referenced by computePolygonArea().
used for transforming coordinates from source CRS to ellipsoid's coordinates
Definition at line 129 of file qgsdistancearea.h.
Referenced by bearing(), measureLine(), measurePolygon(), QgsDistanceArea(), setEllipsoid(), setSourceCrs(), setSourceEpsgCrsId(), and ~QgsDistanceArea().
bool QgsDistanceArea::mProjectionsEnabled [private] |
indicates whether we will transform coordinates
Definition at line 132 of file qgsdistancearea.h.
Referenced by bearing(), computePolygonArea(), measureLine(), measurePolygon(), QgsDistanceArea(), and setProjectionsEnabled().
long QgsDistanceArea::mSourceRefSys [private] |
QString QgsDistanceArea::mEllipsoid [private] |
ellipsoid acronym (from table tbl_ellipsoids)
Definition at line 138 of file qgsdistancearea.h.
Referenced by bearing(), computePolygonArea(), measureLine(), measurePolygon(), and setEllipsoid().
double QgsDistanceArea::mSemiMajor [private] |
ellipsoid parameters
Definition at line 141 of file qgsdistancearea.h.
Referenced by computeAreaInit(), computeDistanceBearing(), and setEllipsoid().
double QgsDistanceArea::mSemiMinor [private] |
Definition at line 141 of file qgsdistancearea.h.
Referenced by computeAreaInit(), computeDistanceBearing(), and setEllipsoid().
double QgsDistanceArea::mInvFlattening [private] |
Definition at line 141 of file qgsdistancearea.h.
Referenced by computeDistanceBearing(), and setEllipsoid().
double QgsDistanceArea::m_QA [private] |
double QgsDistanceArea::m_QB [private] |
double QgsDistanceArea::m_QC [private] |
double QgsDistanceArea::m_QbarA [private] |
double QgsDistanceArea::m_QbarB [private] |
double QgsDistanceArea::m_QbarC [private] |
double QgsDistanceArea::m_QbarD [private] |
double QgsDistanceArea::m_AE [private] |
Definition at line 152 of file qgsdistancearea.h.
Referenced by computeAreaInit(), and computePolygonArea().
double QgsDistanceArea::m_Qp [private] |
Definition at line 153 of file qgsdistancearea.h.
Referenced by computeAreaInit(), and computePolygonArea().
double QgsDistanceArea::m_E [private] |
Definition at line 154 of file qgsdistancearea.h.
Referenced by computeAreaInit(), and computePolygonArea().
double QgsDistanceArea::m_TwoPI [private] |
Definition at line 155 of file qgsdistancearea.h.
Referenced by computeAreaInit(), and computePolygonArea().