OGRFeature *OGROGDILayer::GetFeature( long nFeatureId )
{
ecs_Result *psResult;
if (m_nTotalShapeCount != -1 && nFeatureId > m_nTotalShapeCount)
return NULL;
if (m_iNextShapeId > nFeatureId )
ResetReading();
while(m_iNextShapeId != nFeatureId)
{
psResult = cln_GetNextObject(m_nClientID);
if (ECSSUCCESS(psResult))
m_iNextShapeId++;
else
{
// We probably reached EOF... keep track of shape count.
m_nTotalShapeCount = m_iNextShapeId;
return NULL;
}
}
// OK, we're ready to read the requested feature...
return GetNextFeature();
}
OGRFeature *OGROGDILayer::GetFeature( GIntBig nFeatureId )
{
ecs_Result *psResult;
if (m_nTotalShapeCount != -1 && nFeatureId > m_nTotalShapeCount)
return NULL;
/* Unset spatial filter */
OGRGeometry* poOldFilterGeom = ( m_poFilterGeom != NULL ) ? m_poFilterGeom->clone() : NULL;
if( poOldFilterGeom != NULL )
SetSpatialFilter(NULL);
/* Reset reading if we are not the current layer */
/* WARNING : this does not allow interleaved reading of layers */
if( m_poODS->GetCurrentLayer() != this )
{
m_poODS->SetCurrentLayer(this);
ResetReading();
}
else if ( nFeatureId < m_iNextShapeId )
ResetReading();
while(m_iNextShapeId != nFeatureId)
{
psResult = cln_GetNextObject(m_nClientID);
if (ECSSUCCESS(psResult))
m_iNextShapeId++;
else
{
// We probably reached EOF... keep track of shape count.
m_nTotalShapeCount = m_iNextShapeId;
if( poOldFilterGeom != NULL )
{
SetSpatialFilter(poOldFilterGeom);
delete poOldFilterGeom;
}
return NULL;
}
}
// OK, we're ready to read the requested feature...
OGRFeature* poFeature = GetNextRawFeature();
if( poOldFilterGeom != NULL )
{
SetSpatialFilter(poOldFilterGeom);
delete poOldFilterGeom;
}
return poFeature;
}
OGRFeature *OGROGDILayer::GetNextRawFeature()
{
ecs_Result *psResult;
int i;
OGRFeature *poFeature;
/* -------------------------------------------------------------------- */
/* Retrieve object from OGDI server and create new feature */
/* -------------------------------------------------------------------- */
psResult = cln_GetNextObject(m_nClientID);
if (! ECSSUCCESS(psResult))
{
// We probably reached EOF... keep track of shape count.
m_nTotalShapeCount = m_iNextShapeId - m_nFilteredOutShapes;
return NULL;
}
poFeature = new OGRFeature(m_poFeatureDefn);
poFeature->SetFID( m_iNextShapeId++ );
m_nFeaturesRead++;
/* -------------------------------------------------------------------- */
/* Process geometry */
/* -------------------------------------------------------------------- */
if (m_eFamily == Point)
{
ecs_Point *psPoint = &(ECSGEOM(psResult).point);
OGRPoint *poOGRPoint = new OGRPoint(psPoint->c.x, psPoint->c.y);
poOGRPoint->assignSpatialReference(m_poSpatialRef);
poFeature->SetGeometryDirectly(poOGRPoint);
}
else if (m_eFamily == Line)
{
ecs_Line *psLine = &(ECSGEOM(psResult).line);
OGRLineString *poOGRLine = new OGRLineString();
poOGRLine->setNumPoints( psLine->c.c_len );
for( i=0; i < (int) psLine->c.c_len; i++ )
{
poOGRLine->setPoint(i, psLine->c.c_val[i].x, psLine->c.c_val[i].y);
}
poOGRLine->assignSpatialReference(m_poSpatialRef);
poFeature->SetGeometryDirectly(poOGRLine);
}
else if (m_eFamily == Area)
{
ecs_Area *psArea = &(ECSGEOM(psResult).area);
OGRPolygon *poOGRPolygon = new OGRPolygon();
for(int iRing=0; iRing < (int) psArea->ring.ring_len; iRing++)
{
ecs_FeatureRing *psRing = &(psArea->ring.ring_val[iRing]);
OGRLinearRing *poOGRRing = new OGRLinearRing();
poOGRRing->setNumPoints( psRing->c.c_len );
for( i=0; i < (int) psRing->c.c_len; i++ )
{
poOGRRing->setPoint(i, psRing->c.c_val[i].x,
psRing->c.c_val[i].y);
}
poOGRPolygon->addRingDirectly(poOGRRing);
}
// __TODO__
// When OGR supports polygon centroids then we should carry them here
poOGRPolygon->assignSpatialReference(m_poSpatialRef);
poFeature->SetGeometryDirectly(poOGRPolygon);
}
else if (m_eFamily == Text)
{
// __TODO__
// For now text is treated as a point and string is lost
//
ecs_Text *psText = &(ECSGEOM(psResult).text);
OGRPoint *poOGRPoint = new OGRPoint(psText->c.x, psText->c.y);
poOGRPoint->assignSpatialReference(m_poSpatialRef);
poFeature->SetGeometryDirectly(poOGRPoint);
}
else
{
CPLAssert(FALSE);
}
/* -------------------------------------------------------------------- */
/* Set attributes */
/* -------------------------------------------------------------------- */
char *pszAttrList = ECSOBJECTATTR(psResult);
for( int iField = 0; iField < m_poFeatureDefn->GetFieldCount(); iField++ )
{
char *pszFieldStart;
int nNameLen;
char chSavedChar;
/* parse out the next attribute value */
if( !ecs_FindElement( pszAttrList, &pszFieldStart, &pszAttrList,
&nNameLen, NULL ) )
{
nNameLen = 0;
pszFieldStart = pszAttrList;
}
/* Skip any trailing white space (for string constants). */
if( nNameLen > 0 && pszFieldStart[nNameLen-1] == ' ' )
nNameLen--;
/* skip leading white space */
while( pszFieldStart[0] == ' ' && nNameLen > 0 )
{
pszFieldStart++;
nNameLen--;
}
/* zero terminate the single field value, but save the */
/* character we overwrote, so we can restore it when done. */
chSavedChar = pszFieldStart[nNameLen];
pszFieldStart[nNameLen] = '\0';
/* OGR takes care of all field type conversions for us! */
poFeature->SetField(iField, pszFieldStart);
pszFieldStart[nNameLen] = chSavedChar;
}
/* -------------------------------------------------------------------- */
/* Apply the text associated with text features if appropriate. */
/* -------------------------------------------------------------------- */
if( m_eFamily == Text )
{
poFeature->SetField( "text", ECSGEOM(psResult).text.desc );
}
return poFeature;
}