ultimatepp/bazaar/plugin/gdal/ogr/ogrcurve.cpp
cxl 23ff1e7e82 .gdal moved to bazaar
git-svn-id: svn://ultimatepp.org/upp/trunk@9273 f0d560ea-af0d-0410-9eb7-867de7ffcac7
2015-12-07 13:36:24 +00:00

390 lines
12 KiB
C++

/******************************************************************************
* $Id: ogrcurve.cpp 28004 2014-11-26 09:58:44Z rouault $
*
* Project: OpenGIS Simple Features Reference Implementation
* Purpose: The OGRCurve geometry class.
* Author: Frank Warmerdam, warmerda@home.com
*
******************************************************************************
* Copyright (c) 1999, Frank Warmerdam
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
****************************************************************************/
#include "ogr_geometry.h"
#include "ogr_p.h"
CPL_CVSID("$Id: ogrcurve.cpp 28004 2014-11-26 09:58:44Z rouault $");
/************************************************************************/
/* OGRCurve() */
/************************************************************************/
OGRCurve::OGRCurve()
{
}
/************************************************************************/
/* ~OGRCurve() */
/************************************************************************/
OGRCurve::~OGRCurve()
{
}
/************************************************************************/
/* getDimension() */
/************************************************************************/
int OGRCurve::getDimension() const
{
return 1;
}
/************************************************************************/
/* get_IsClosed() */
/************************************************************************/
/**
* \brief Return TRUE if curve is closed.
*
* Tests if a curve is closed. A curve is closed if its start point is
* equal to its end point.
*
* This method relates to the SFCOM ICurve::get_IsClosed() method.
*
* @return TRUE if closed, else FALSE.
*/
int OGRCurve::get_IsClosed() const
{
OGRPoint oStartPoint, oEndPoint;
StartPoint( &oStartPoint );
EndPoint( &oEndPoint );
if( oStartPoint.getX() == oEndPoint.getX()
&& oStartPoint.getY() == oEndPoint.getY() )
{
return TRUE;
}
else
{
return FALSE;
}
}
/**
* \fn double OGRCurve::get_Length() const;
*
* \brief Returns the length of the curve.
*
* This method relates to the SFCOM ICurve::get_Length() method.
*
* @return the length of the curve, zero if the curve hasn't been
* initialized.
*/
/**
* \fn void OGRCurve::StartPoint( OGRPoint * poPoint ) const;
*
* \brief Return the curve start point.
*
* This method relates to the SF COM ICurve::get_StartPoint() method.
*
* @param poPoint the point to be assigned the start location.
*/
/**
* \fn void OGRCurve::EndPoint( OGRPoint * poPoint ) const;
*
* \brief Return the curve end point.
*
* This method relates to the SF COM ICurve::get_EndPoint() method.
*
* @param poPoint the point to be assigned the end location.
*/
/**
* \fn void OGRCurve::Value( double dfDistance, OGRPoint * poPoint ) const;
*
* \brief Fetch point at given distance along curve.
*
* This method relates to the SF COM ICurve::get_Value() method.
*
* This function is the same as the C function OGR_G_Value().
*
* @param dfDistance distance along the curve at which to sample position.
* This distance should be between zero and get_Length()
* for this curve.
* @param poPoint the point to be assigned the curve position.
*/
/**
* \fn OGRLineString* OGRCurve::CurveToLine( double dfMaxAngleStepSizeDegrees, const char* const* papszOptions ) const;
*
* \brief Return a linestring from a curve geometry.
*
* The returned geometry is a new instance whose ownership belongs to the caller.
*
* If the dfMaxAngleStepSizeDegrees is zero, then a default value will be
* used. This is currently 4 degrees unless the user has overridden the
* value with the OGR_ARC_STEPSIZE configuration variable.
*
* This method relates to the ISO SQL/MM Part 3 ICurve::CurveToLine() method.
*
* This function is the same as C function OGR_G_CurveToLine().
*
* @param dfMaxAngleStepSizeDegrees the largest step in degrees along the
* arc, zero to use the default setting.
* @param papszOptions options as a null-terminated list of strings or NULL.
* See OGRGeometryFactory::curveToLineString() for valid options.
*
* @return a line string approximating the curve
*
* @since GDAL 2.0
*/
/**
* \fn int OGRCurve::getNumPoints() const;
*
* \brief Return the number of points of a curve geometry.
*
*
* This method, as a method of OGRCurve, does not relate to a standard.
* For circular strings or linestrings, it returns the number of points,
* conforming to SF COM NumPoints().
* For compound curves, it returns the sum of the number of points of each
* of its components (non including intermediate starting/ending points of
* the different parts).
*
* @return the number of points of the curve.
*
* @since GDAL 2.0
*/
/**
* \fn OGRPointIterator* OGRCurve::getPointIterator() const;
*
* \brief Returns a point iterator over the curve.
*
* The curve must not be modified while an iterator exists on it.
*
* The iterator must be destroyed with OGRPointIterator::destroy().
*
* @return a point iterator over the curve.
*
* @since GDAL 2.0
*/
/**
* \fn double OGRCurve::get_Area() const;
*
* \brief Get the area of the (closed) curve.
*
* This method is designed to be used by OGRCurvePolygon::get_Area().
*
* @return the area of the feature in square units of the spatial reference
* system in use.
*
* @since GDAL 2.0
*/
/**
* \fn double OGRCurve::get_AreaOfCurveSegments() const;
*
* \brief Get the area of the purely curve portions of a (closed) curve.
*
* This method is designed to be used on a closed convex curve.
*
* @return the area of the feature in square units of the spatial reference
* system in use.
*
* @since GDAL 2.0
*/
/************************************************************************/
/* IsConvex() */
/************************************************************************/
/**
* \brief Returns if a (closed) curve forms a convex shape.
*
* @return TRUE if the curve forms a convex shape.
*
* @since GDAL 2.0
*/
OGRBoolean OGRCurve::IsConvex() const
{
OGRBoolean bRet = TRUE;
OGRPointIterator* poPointIter = getPointIterator();
OGRPoint p1, p2, p3;
if( poPointIter->getNextPoint(&p1) &&
poPointIter->getNextPoint(&p2) )
{
while( poPointIter->getNextPoint(&p3) )
{
double crossproduct = (p2.getX() - p1.getX()) * (p3.getY() - p2.getY()) -
(p2.getY() - p1.getY()) * (p3.getX() - p2.getX());
if( crossproduct > 0 )
{
bRet = FALSE;
break;
}
p1.setX(p2.getX());
p1.setY(p2.getY());
p2.setX(p3.getX());
p2.setY(p3.getY());
}
}
delete poPointIter;
return bRet;
}
/************************************************************************/
/* CastToCompoundCurve() */
/************************************************************************/
/**
* \brief Cast to compound curve
*
* The passed in geometry is consumed and a new one returned (or NULL in case
* of failure)
*
* @param poCurve the input geometry - ownership is passed to the method.
* @return new geometry
*
* @since GDAL 2.0
*/
OGRCompoundCurve* OGRCurve::CastToCompoundCurve(OGRCurve* poCurve)
{
OGRCompoundCurve* poCC = new OGRCompoundCurve();
if( poCurve->getGeometryType() == wkbLineString )
poCurve = CastToLineString(poCurve);
if( !poCurve->IsEmpty() && poCC->addCurveDirectly(poCurve) != OGRERR_NONE )
{
delete poCC;
delete poCurve;
return NULL;
}
poCC->assignSpatialReference(poCurve->getSpatialReference());
return poCC;
}
/************************************************************************/
/* CastToLineString() */
/************************************************************************/
/**
* \brief Cast to linestring
*
* The passed in geometry is consumed and a new one returned (or NULL in case
* of failure)
*
* @param poCurve the input geometry - ownership is passed to the method.
* @return new geometry.
*
* @since GDAL 2.0
*/
OGRLineString* OGRCurve::CastToLineString(OGRCurve* poCurve)
{
OGRCurveCasterToLineString pfn = poCurve->GetCasterToLineString();
return pfn(poCurve);
}
/************************************************************************/
/* CastToLinearRing() */
/************************************************************************/
/**
* \brief Cast to linear ring
*
* The passed in geometry is consumed and a new one returned (or NULL in case
* of failure)
*
* @param poCurve the input geometry - ownership is passed to the method.
* @return new geometry.
*
* @since GDAL 2.0
*/
OGRLinearRing* OGRCurve::CastToLinearRing(OGRCurve* poCurve)
{
OGRCurveCasterToLinearRing pfn = poCurve->GetCasterToLinearRing();
return pfn(poCurve);
}
/************************************************************************/
/* ContainsPoint() */
/************************************************************************/
/**
* \brief Returns if a point is contained in a (closed) curve.
*
* Final users should use OGRGeometry::Contains() instead.
*
* @param p the point to test
* @return TRUE if it is inside the curve, FALSE otherwise or -1 if unknown.
*
* @since GDAL 2.0
*/
int OGRCurve::ContainsPoint( CPL_UNUSED const OGRPoint* p ) const
{
return -1;
}
/************************************************************************/
/* ~OGRPointIterator() */
/************************************************************************/
OGRPointIterator::~OGRPointIterator()
{
}
/**
* \fn OGRBoolean OGRPointIterator::getNextPoint(OGRPoint* p);
*
* \brief Returns the next point followed by the iterator.
*
* @param p point to fill.
*
* @return TRUE in case of success, or FALSE if the end of the curve is reached.
*
* @since GDAL 2.0
*/
/************************************************************************/
/* destroy() */
/************************************************************************/
/**
* \brief Destroys a point iterator.
*
* @since GDAL 2.0
*/
void OGRPointIterator::destroy(OGRPointIterator* poIter)
{
delete poIter;
}