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/******************************************************************************
* $Id: fpolygonize.cpp 22501 2011-06-04 21:28:47Z rouault $
*
* Project: GDAL
* Purpose: Version of Raster to Polygon Converter using float buffers.
* Author: Jorge Arevalo, jorge.arevalo@deimos-space.com. Most of the code
* taken from GDALPolygonize.cpp, by Frank Warmerdam, warmerdam@pobox.com
*
******************************************************************************
* Copyright (c) 2011, Jorge Arevalo
* Copyright (c) 2008, 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 "gdal_alg_priv.h"
#include "cpl_conv.h"
#include "cpl_string.h"
#include <vector>
CPL_CVSID("$Id: fpolygonize.cpp 22501 2011-06-04 21:28:47Z rouault $");
#define GP_NODATA_MARKER -51502112
#ifdef OGR_ENABLED
/******************************************************************************/
/* GDALFloatEquals() */
/* Code from: */
/* http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm */
/******************************************************************************/
GBool GDALFloatEquals(float A, float B)
{
/**
* This function will allow maxUlps-1 floats between A and B.
*/
int maxUlps = MAX_ULPS;
int aInt, bInt;
/**
* Make sure maxUlps is non-negative and small enough that the default NAN
* won't compare as equal to anything.
*/
CPLAssert(maxUlps > 0 && maxUlps < 4 * 1024 * 1024);
/**
* This assignation could violate strict aliasing. It causes a warning with
* gcc -O2. Use of memcpy preferred. Credits for Even Rouault. Further info
* at http://trac.osgeo.org/gdal/ticket/4005#comment:6
*/
//int aInt = *(int*)&A;
memcpy(&aInt, &A, 4);
/**
* Make aInt lexicographically ordered as a twos-complement int
*/
if (aInt < 0)
aInt = 0x80000000 - aInt;
/**
* Make bInt lexicographically ordered as a twos-complement int
*/
//int bInt = *(int*)&B;
memcpy(&bInt, &B, 4);
if (bInt < 0)
bInt = 0x80000000 - bInt;
int intDiff = abs(aInt - bInt);
if (intDiff <= maxUlps)
return true;
return false;
}
/************************************************************************/
/* ==================================================================== */
/* RPolygonF */
/* */
/* This is a helper class to hold polygons while they are being */
/* formed in memory, and to provide services to coalesce a much */
/* of edge sections into complete rings. */
/* ==================================================================== */
/************************************************************************/
class RPolygonF {
public:
RPolygonF( float fValue ) { fPolyValue = fValue; nLastLineUpdated = -1; }
float fPolyValue;
int nLastLineUpdated;
std::vector< std::vector<int> > aanXY;
void AddSegment( int x1, int y1, int x2, int y2 );
void Dump();
void Coalesce();
void Merge( int iBaseString, int iSrcString, int iDirection );
};
/************************************************************************/
/* Dump() */
/************************************************************************/
void RPolygonF::Dump()
{
size_t iString;
printf( "RPolygonF: Value=%f, LastLineUpdated=%d\n",
fPolyValue, nLastLineUpdated );
for( iString = 0; iString < aanXY.size(); iString++ )
{
std::vector<int> &anString = aanXY[iString];
size_t iVert;
printf( " String %d:\n", (int) iString );
for( iVert = 0; iVert < anString.size(); iVert += 2 )
{
printf( " (%d,%d)\n", anString[iVert], anString[iVert+1] );
}
}
}
/************************************************************************/
/* Coalesce() */
/************************************************************************/
void RPolygonF::Coalesce()
{
size_t iBaseString;
/* -------------------------------------------------------------------- */
/* Iterate over loops starting from the first, trying to merge */
/* other segments into them. */
/* -------------------------------------------------------------------- */
for( iBaseString = 0; iBaseString < aanXY.size(); iBaseString++ )
{
std::vector<int> &anBase = aanXY[iBaseString];
int bMergeHappened = TRUE;
/* -------------------------------------------------------------------- */
/* Keep trying to merge the following strings into our target */
/* "base" string till we have tried them all once without any */
/* mergers. */
/* -------------------------------------------------------------------- */
while( bMergeHappened )
{
size_t iString;
bMergeHappened = FALSE;
/* -------------------------------------------------------------------- */
/* Loop over the following strings, trying to find one we can */
/* merge onto the end of our base string. */
/* -------------------------------------------------------------------- */
for( iString = iBaseString+1;
iString < aanXY.size();
iString++ )
{
std::vector<int> &anString = aanXY[iString];
if( anBase[anBase.size()-2] == anString[0]
&& anBase[anBase.size()-1] == anString[1] )
{
Merge( iBaseString, iString, 1 );
bMergeHappened = TRUE;
}
else if( anBase[anBase.size()-2] == anString[anString.size()-2]
&& anBase[anBase.size()-1] == anString[anString.size()-1] )
{
Merge( iBaseString, iString, -1 );
bMergeHappened = TRUE;
}
}
}
/* At this point our loop *should* be closed! */
CPLAssert( anBase[0] == anBase[anBase.size()-2]
&& anBase[1] == anBase[anBase.size()-1] );
}
}
/************************************************************************/
/* Merge() */
/************************************************************************/
void RPolygonF::Merge( int iBaseString, int iSrcString, int iDirection )
{
std::vector<int> &anBase = aanXY[iBaseString];
std::vector<int> &anString = aanXY[iSrcString];
int iStart, iEnd, i;
if( iDirection == 1 )
{
iStart = 1;
iEnd = anString.size() / 2;
}
else
{
iStart = anString.size() / 2 - 2;
iEnd = -1;
}
for( i = iStart; i != iEnd; i += iDirection )
{
anBase.push_back( anString[i*2+0] );
anBase.push_back( anString[i*2+1] );
}
if( iSrcString < ((int) aanXY.size())-1 )
aanXY[iSrcString] = aanXY[aanXY.size()-1];
size_t nSize = aanXY.size();
aanXY.resize(nSize-1);
}
/************************************************************************/
/* AddSegment() */
/************************************************************************/
void RPolygonF::AddSegment( int x1, int y1, int x2, int y2 )
{
nLastLineUpdated = MAX(y1, y2);
/* -------------------------------------------------------------------- */
/* Is there an existing string ending with this? */
/* -------------------------------------------------------------------- */
size_t iString;
for( iString = 0; iString < aanXY.size(); iString++ )
{
std::vector<int> &anString = aanXY[iString];
size_t nSSize = anString.size();
if( anString[nSSize-2] == x1
&& anString[nSSize-1] == y1 )
{
int nTemp;
nTemp = x2;
x2 = x1;
x1 = nTemp;
nTemp = y2;
y2 = y1;
y1 = nTemp;
}
if( anString[nSSize-2] == x2
&& anString[nSSize-1] == y2 )
{
// We are going to add a segment, but should we just extend
// an existing segment already going in the right direction?
int nLastLen = MAX(ABS(anString[nSSize-4]-anString[nSSize-2]),
ABS(anString[nSSize-3]-anString[nSSize-1]));
if( nSSize >= 4
&& (anString[nSSize-4] - anString[nSSize-2]
== (anString[nSSize-2] - x1)*nLastLen)
&& (anString[nSSize-3] - anString[nSSize-1]
== (anString[nSSize-1] - y1)*nLastLen) )
{
anString.pop_back();
anString.pop_back();
}
anString.push_back( x1 );
anString.push_back( y1 );
return;
}
}
/* -------------------------------------------------------------------- */
/* Create a new string. */
/* -------------------------------------------------------------------- */
size_t nSize = aanXY.size();
aanXY.resize(nSize + 1);
std::vector<int> &anString = aanXY[nSize];
anString.push_back( x1 );
anString.push_back( y1 );
anString.push_back( x2 );
anString.push_back( y2 );
return;
}
/************************************************************************/
/* ==================================================================== */
/* End of RPolygonF */
/* ==================================================================== */
/************************************************************************/
/************************************************************************/
/* AddEdges() */
/* */
/* Examine one pixel and compare to its neighbour above */
/* (previous) and right. If they are different polygon ids */
/* then add the pixel edge to this polygon and the one on the */
/* other side of the edge. */
/************************************************************************/
static void AddEdges( GInt32 *panThisLineId, GInt32 *panLastLineId,
GInt32 *panPolyIdMap, float *pafPolyValue,
RPolygonF **papoPoly, int iX, int iY )
{
int nThisId = panThisLineId[iX];
int nRightId = panThisLineId[iX+1];
int nPreviousId = panLastLineId[iX];
int iXReal = iX - 1;
if( nThisId != -1 )
nThisId = panPolyIdMap[nThisId];
if( nRightId != -1 )
nRightId = panPolyIdMap[nRightId];
if( nPreviousId != -1 )
nPreviousId = panPolyIdMap[nPreviousId];
if( nThisId != nPreviousId )
{
if( nThisId != -1 )
{
if( papoPoly[nThisId] == NULL )
papoPoly[nThisId] = new RPolygonF( pafPolyValue[nThisId] );
papoPoly[nThisId]->AddSegment( iXReal, iY, iXReal+1, iY );
}
if( nPreviousId != -1 )
{
if( papoPoly[nPreviousId] == NULL )
papoPoly[nPreviousId] = new RPolygonF(pafPolyValue[nPreviousId]);
papoPoly[nPreviousId]->AddSegment( iXReal, iY, iXReal+1, iY );
}
}
if( nThisId != nRightId )
{
if( nThisId != -1 )
{
if( papoPoly[nThisId] == NULL )
papoPoly[nThisId] = new RPolygonF(pafPolyValue[nThisId]);
papoPoly[nThisId]->AddSegment( iXReal+1, iY, iXReal+1, iY+1 );
}
if( nRightId != -1 )
{
if( papoPoly[nRightId] == NULL )
papoPoly[nRightId] = new RPolygonF(pafPolyValue[nRightId]);
papoPoly[nRightId]->AddSegment( iXReal+1, iY, iXReal+1, iY+1 );
}
}
}
/************************************************************************/
/* EmitPolygonToLayer() */
/************************************************************************/
static CPLErr
EmitPolygonToLayer( OGRLayerH hOutLayer, int iPixValField,
RPolygonF *poRPoly, double *padfGeoTransform )
{
OGRFeatureH hFeat;
OGRGeometryH hPolygon;
/* -------------------------------------------------------------------- */
/* Turn bits of lines into coherent rings. */
/* -------------------------------------------------------------------- */
poRPoly->Coalesce();
/* -------------------------------------------------------------------- */
/* Create the polygon geometry. */
/* -------------------------------------------------------------------- */
size_t iString;
hPolygon = OGR_G_CreateGeometry( wkbPolygon );
for( iString = 0; iString < poRPoly->aanXY.size(); iString++ )
{
std::vector<int> &anString = poRPoly->aanXY[iString];
OGRGeometryH hRing = OGR_G_CreateGeometry( wkbLinearRing );
int iVert;
// we go last to first to ensure the linestring is allocated to
// the proper size on the first try.
for( iVert = anString.size()/2 - 1; iVert >= 0; iVert-- )
{
double dfX, dfY;
int nPixelX, nPixelY;
nPixelX = anString[iVert*2];
nPixelY = anString[iVert*2+1];
dfX = padfGeoTransform[0]
+ nPixelX * padfGeoTransform[1]
+ nPixelY * padfGeoTransform[2];
dfY = padfGeoTransform[3]
+ nPixelX * padfGeoTransform[4]
+ nPixelY * padfGeoTransform[5];
OGR_G_SetPoint_2D( hRing, iVert, dfX, dfY );
}
OGR_G_AddGeometryDirectly( hPolygon, hRing );
}
/* -------------------------------------------------------------------- */
/* Create the feature object. */
/* -------------------------------------------------------------------- */
hFeat = OGR_F_Create( OGR_L_GetLayerDefn( hOutLayer ) );
OGR_F_SetGeometryDirectly( hFeat, hPolygon );
if( iPixValField >= 0 )
OGR_F_SetFieldDouble( hFeat, iPixValField, (double)poRPoly->fPolyValue );
/* -------------------------------------------------------------------- */
/* Write the to the layer. */
/* -------------------------------------------------------------------- */
CPLErr eErr = CE_None;
if( OGR_L_CreateFeature( hOutLayer, hFeat ) != OGRERR_NONE )
eErr = CE_Failure;
OGR_F_Destroy( hFeat );
return eErr;
}
/************************************************************************/
/* GPMaskImageData() */
/* */
/* Mask out image pixels to a special nodata value if the mask */
/* band is zero. */
/************************************************************************/
static CPLErr
GPMaskImageData( GDALRasterBandH hMaskBand, GByte* pabyMaskLine, int iY, int nXSize,
float *pafImageLine )
{
CPLErr eErr;
eErr = GDALRasterIO( hMaskBand, GF_Read, 0, iY, nXSize, 1,
pabyMaskLine, nXSize, 1, GDT_Byte, 0, 0 );
if( eErr == CE_None )
{
int i;
for( i = 0; i < nXSize; i++ )
{
if( pabyMaskLine[i] == 0 )
pafImageLine[i] = GP_NODATA_MARKER;
}
}
return eErr;
}
#endif // OGR_ENABLED
/************************************************************************/
/* GDALFPolygonize() */
/************************************************************************/
/**
* Create polygon coverage from raster data.
*
* This function creates vector polygons for all connected regions of pixels in
* the raster sharing a common pixel value. Optionally each polygon may be
* labelled with the pixel value in an attribute. Optionally a mask band
* can be provided to determine which pixels are eligible for processing.
*
* The source pixel band values are read into a 32bit float buffer. If you want
* to use a (probably faster) version using signed 32bit integer buffer, see
* GDALPolygonize() at polygonize.cpp.
*
* Polygon features will be created on the output layer, with polygon
* geometries representing the polygons. The polygon geometries will be
* in the georeferenced coordinate system of the image (based on the
* geotransform of the source dataset). It is acceptable for the output
* layer to already have features. Note that GDALFPolygonize() does not
* set the coordinate system on the output layer. Application code should
* do this when the layer is created, presumably matching the raster
* coordinate system.
*
* The algorithm used attempts to minimize memory use so that very large
* rasters can be processed. However, if the raster has many polygons
* or very large/complex polygons, the memory use for holding polygon
* enumerations and active polygon geometries may grow to be quite large.
*
* The algorithm will generally produce very dense polygon geometries, with
* edges that follow exactly on pixel boundaries for all non-interior pixels.
* For non-thematic raster data (such as satellite images) the result will
* essentially be one small polygon per pixel, and memory and output layer
* sizes will be substantial. The algorithm is primarily intended for
* relatively simple thematic imagery, masks, and classification results.
*
* @param hSrcBand the source raster band to be processed.
* @param hMaskBand an optional mask band. All pixels in the mask band with a
* value other than zero will be considered suitable for collection as
* polygons.
* @param hOutLayer the vector feature layer to which the polygons should
* be written.
* @param iPixValField the attribute field index indicating the feature
* attribute into which the pixel value of the polygon should be written.
* @param papszOptions a name/value list of additional options
* <dl>
* <dt>"8CONNECTED":</dt> May be set to "8" to use 8 connectedness.
* Otherwise 4 connectedness will be applied to the algorithm
* </dl>
* @param pfnProgress callback for reporting algorithm progress matching the
* GDALProgressFunc() semantics. May be NULL.
* @param pProgressArg callback argument passed to pfnProgress.
*
* @return CE_None on success or CE_Failure on a failure.
*
* @since GDAL 1.9.0
*/
CPLErr CPL_STDCALL
GDALFPolygonize( GDALRasterBandH hSrcBand,
GDALRasterBandH hMaskBand,
OGRLayerH hOutLayer, int iPixValField,
char **papszOptions,
GDALProgressFunc pfnProgress,
void * pProgressArg )
{
#ifndef OGR_ENABLED
CPLError(CE_Failure, CPLE_NotSupported, "GDALFPolygonize() unimplemented in a non OGR build");
return CE_Failure;
#else
VALIDATE_POINTER1( hSrcBand, "GDALFPolygonize", CE_Failure );
VALIDATE_POINTER1( hOutLayer, "GDALFPolygonize", CE_Failure );
if( pfnProgress == NULL )
pfnProgress = GDALDummyProgress;
int nConnectedness = CSLFetchNameValue( papszOptions, "8CONNECTED" ) ? 8 : 4;
/* -------------------------------------------------------------------- */
/* Confirm our output layer will support feature creation. */
/* -------------------------------------------------------------------- */
if( !OGR_L_TestCapability( hOutLayer, OLCSequentialWrite ) )
{
CPLError( CE_Failure, CPLE_AppDefined,
"Output feature layer does not appear to support creation\n"
"of features in GDALFPolygonize()." );
return CE_Failure;
}
/* -------------------------------------------------------------------- */
/* Allocate working buffers. */
/* -------------------------------------------------------------------- */
CPLErr eErr = CE_None;
int nXSize = GDALGetRasterBandXSize( hSrcBand );
int nYSize = GDALGetRasterBandYSize( hSrcBand );
float *pafLastLineVal = (float *) VSIMalloc2(sizeof(float),nXSize + 2);
float *pafThisLineVal = (float *) VSIMalloc2(sizeof(float),nXSize + 2);
GInt32 *panLastLineId = (GInt32 *) VSIMalloc2(sizeof(GInt32),nXSize + 2);
GInt32 *panThisLineId = (GInt32 *) VSIMalloc2(sizeof(GInt32),nXSize + 2);
GByte *pabyMaskLine = (hMaskBand != NULL) ? (GByte *) VSIMalloc(nXSize) : NULL;
if (pafLastLineVal == NULL || pafThisLineVal == NULL ||
panLastLineId == NULL || panThisLineId == NULL ||
(hMaskBand != NULL && pabyMaskLine == NULL))
{
CPLError(CE_Failure, CPLE_OutOfMemory,
"Could not allocate enough memory for temporary buffers");
CPLFree( panThisLineId );
CPLFree( panLastLineId );
CPLFree( pafThisLineVal );
CPLFree( pafLastLineVal );
CPLFree( pabyMaskLine );
return CE_Failure;
}
/* -------------------------------------------------------------------- */
/* Get the geotransform, if there is one, so we can convert the */
/* vectors into georeferenced coordinates. */
/* -------------------------------------------------------------------- */
GDALDatasetH hSrcDS = GDALGetBandDataset( hSrcBand );
double adfGeoTransform[6] = { 0.0, 1.0, 0.0, 0.0, 0.0, 1.0 };
if( hSrcDS )
GDALGetGeoTransform( hSrcDS, adfGeoTransform );
/* -------------------------------------------------------------------- */
/* The first pass over the raster is only used to build up the */
/* polygon id map so we will know in advance what polygons are */
/* what on the second pass. */
/* -------------------------------------------------------------------- */
int iY;
GDALRasterFPolygonEnumerator oFirstEnum(nConnectedness);
for( iY = 0; eErr == CE_None && iY < nYSize; iY++ )
{
eErr = GDALRasterIO(
hSrcBand,
GF_Read, 0, iY, nXSize, 1,
pafThisLineVal, nXSize, 1, GDT_Float32, 0, 0 );
if( eErr == CE_None && hMaskBand != NULL )
eErr = GPMaskImageData( hMaskBand, pabyMaskLine, iY, nXSize,
pafThisLineVal );
if( iY == 0 )
oFirstEnum.ProcessLine(
NULL, pafThisLineVal, NULL, panThisLineId, nXSize );
else
oFirstEnum.ProcessLine(
pafLastLineVal, pafThisLineVal,
panLastLineId, panThisLineId,
nXSize );
// swap lines
float * pafTmp = pafLastLineVal;
pafLastLineVal = pafThisLineVal;
pafThisLineVal = pafTmp;
GInt32 * panTmp = panThisLineId;
panThisLineId = panLastLineId;
panLastLineId = panTmp;
/* -------------------------------------------------------------------- */
/* Report progress, and support interrupts. */
/* -------------------------------------------------------------------- */
if( eErr == CE_None
&& !pfnProgress( 0.10 * ((iY+1) / (double) nYSize),
"", pProgressArg ) )
{
CPLError( CE_Failure, CPLE_UserInterrupt, "User terminated" );
eErr = CE_Failure;
}
}
/* -------------------------------------------------------------------- */
/* Make a pass through the maps, ensuring every polygon id */
/* points to the final id it should use, not an intermediate */
/* value. */
/* -------------------------------------------------------------------- */
oFirstEnum.CompleteMerges();
/* -------------------------------------------------------------------- */
/* Initialize ids to -1 to serve as a nodata value for the */
/* previous line, and past the beginning and end of the */
/* scanlines. */
/* -------------------------------------------------------------------- */
int iX;
panThisLineId[0] = -1;
panThisLineId[nXSize+1] = -1;
for( iX = 0; iX < nXSize+2; iX++ )
panLastLineId[iX] = -1;
/* -------------------------------------------------------------------- */
/* We will use a new enumerator for the second pass primariliy */
/* so we can preserve the first pass map. */
/* -------------------------------------------------------------------- */
GDALRasterFPolygonEnumerator oSecondEnum(nConnectedness);
RPolygonF **papoPoly = (RPolygonF **)
CPLCalloc(sizeof(RPolygonF*),oFirstEnum.nNextPolygonId);
/* ==================================================================== */
/* Second pass during which we will actually collect polygon */
/* edges as geometries. */
/* ==================================================================== */
for( iY = 0; eErr == CE_None && iY < nYSize+1; iY++ )
{
/* -------------------------------------------------------------------- */
/* Read the image data. */
/* -------------------------------------------------------------------- */
if( iY < nYSize )
{
eErr = GDALRasterIO( hSrcBand, GF_Read, 0, iY, nXSize, 1,
pafThisLineVal, nXSize, 1, GDT_Float32, 0, 0 );
if( eErr == CE_None && hMaskBand != NULL )
eErr = GPMaskImageData( hMaskBand, pabyMaskLine, iY, nXSize,
pafThisLineVal );
}
if( eErr != CE_None )
continue;
/* -------------------------------------------------------------------- */
/* Determine what polygon the various pixels belong to (redoing */
/* the same thing done in the first pass above). */
/* -------------------------------------------------------------------- */
if( iY == nYSize )
{
for( iX = 0; iX < nXSize+2; iX++ )
panThisLineId[iX] = -1;
}
else if( iY == 0 )
oSecondEnum.ProcessLine(
NULL, pafThisLineVal, NULL, panThisLineId+1, nXSize );
else
oSecondEnum.ProcessLine(
pafLastLineVal, pafThisLineVal,
panLastLineId+1, panThisLineId+1,
nXSize );
/* -------------------------------------------------------------------- */
/* Add polygon edges to our polygon list for the pixel */
/* boundaries within and above this line. */
/* -------------------------------------------------------------------- */
for( iX = 0; iX < nXSize+1; iX++ )
{
AddEdges( panThisLineId, panLastLineId,
oFirstEnum.panPolyIdMap, oFirstEnum.pafPolyValue,
papoPoly, iX, iY );
}
/* -------------------------------------------------------------------- */
/* Periodically we scan out polygons and write out those that */
/* haven't been added to on the last line as we can be sure */
/* they are complete. */
/* -------------------------------------------------------------------- */
if( iY % 8 == 7 )
{
for( iX = 0;
eErr == CE_None && iX < oSecondEnum.nNextPolygonId;
iX++ )
{
if( papoPoly[iX] && papoPoly[iX]->nLastLineUpdated < iY-1 )
{
if( hMaskBand == NULL
|| !GDALFloatEquals(papoPoly[iX]->fPolyValue, GP_NODATA_MARKER) )
{
eErr =
EmitPolygonToLayer( hOutLayer, iPixValField,
papoPoly[iX], adfGeoTransform );
}
delete papoPoly[iX];
papoPoly[iX] = NULL;
}
}
}
/* -------------------------------------------------------------------- */
/* Swap pixel value, and polygon id lines to be ready for the */
/* next line. */
/* -------------------------------------------------------------------- */
float *pafTmp = pafLastLineVal;
pafLastLineVal = pafThisLineVal;
pafThisLineVal = pafTmp;
GInt32 *panTmp = panThisLineId;
panThisLineId = panLastLineId;
panLastLineId = panTmp;
/* -------------------------------------------------------------------- */
/* Report progress, and support interrupts. */
/* -------------------------------------------------------------------- */
if( eErr == CE_None
&& !pfnProgress( 0.10 + 0.90 * ((iY+1) / (double) nYSize),
"", pProgressArg ) )
{
CPLError( CE_Failure, CPLE_UserInterrupt, "User terminated" );
eErr = CE_Failure;
}
}
/* -------------------------------------------------------------------- */
/* Make a cleanup pass for all unflushed polygons. */
/* -------------------------------------------------------------------- */
for( iX = 0; eErr == CE_None && iX < oSecondEnum.nNextPolygonId; iX++ )
{
if( papoPoly[iX] )
{
if( hMaskBand == NULL
|| !GDALFloatEquals(papoPoly[iX]->fPolyValue, GP_NODATA_MARKER) )
{
eErr =
EmitPolygonToLayer( hOutLayer, iPixValField,
papoPoly[iX], adfGeoTransform );
}
delete papoPoly[iX];
papoPoly[iX] = NULL;
}
}
/* -------------------------------------------------------------------- */
/* Cleanup */
/* -------------------------------------------------------------------- */
CPLFree( panThisLineId );
CPLFree( panLastLineId );
CPLFree( pafThisLineVal );
CPLFree( pafLastLineVal );
CPLFree( pabyMaskLine );
CPLFree( papoPoly );
return eErr;
#endif // OGR_ENABLED
}
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