//! Simplifies the OGR-geometry (Removing duplicated points) when is applied the specified map2pixel context
bool QgsOgrMapToPixelSimplifier::simplifyOgrGeometry( OGRGeometry* geometry, bool isaLinearRing )
{
OGRwkbGeometryType wkbGeometryType = wkbFlatten( geometry->getGeometryType() );
// Simplify the geometry rewriting temporally its WKB-stream for saving calloc's.
if ( wkbGeometryType == wkbLineString )
{
OGRLineString* lineString = ( OGRLineString* )geometry;
int numPoints = lineString->getNumPoints();
if (( isaLinearRing && numPoints <= 5 ) || ( !isaLinearRing && numPoints <= 2 ) ) return false;
OGREnvelope env;
geometry->getEnvelope( &env );
QgsRectangle envelope( env.MinX, env.MinY, env.MaxX, env.MaxY );
// Can replace the geometry by its BBOX ?
if (( mSimplifyFlags & QgsMapToPixelSimplifier::SimplifyEnvelope ) && canbeGeneralizedByMapBoundingBox( envelope ) )
{
OGRRawPoint* points = NULL;
int numPoints = 0;
double x1 = envelope.xMinimum();
double y1 = envelope.yMinimum();
double x2 = envelope.xMaximum();
double y2 = envelope.yMaximum();
if ( isaLinearRing )
{
numPoints = 5;
points = mallocPoints( numPoints );
points[0].x = x1; points[0].y = y1;
points[1].x = x2; points[1].y = y1;
points[2].x = x2; points[2].y = y2;
points[3].x = x1; points[3].y = y2;
points[4].x = x1; points[4].y = y1;
}
else
{
numPoints = 2;
points = mallocPoints( numPoints );
points[0].x = x1; points[0].y = y1;
points[1].x = x2; points[1].y = y2;
}
lineString->setPoints( numPoints, points );
lineString->flattenTo2D();
return true;
}
else
if ( mSimplifyFlags & QgsMapToPixelSimplifier::SimplifyGeometry )
{
QGis::GeometryType geometryType = isaLinearRing ? QGis::Polygon : QGis::Line;
int numSimplifiedPoints = 0;
OGRRawPoint* points = mallocPoints( numPoints );
double* xptr = ( double* )points;
double* yptr = xptr + 1;
lineString->getPoints( points );
if ( simplifyOgrGeometry( geometryType, envelope, xptr, 16, yptr, 16, numPoints, numSimplifiedPoints ) )
{
lineString->setPoints( numSimplifiedPoints, points );
lineString->flattenTo2D();
}
return numSimplifiedPoints != numPoints;
}
}
else
if ( wkbGeometryType == wkbPolygon )
{
OGRPolygon* polygon = ( OGRPolygon* )geometry;
bool result = simplifyOgrGeometry( polygon->getExteriorRing(), true );
for ( int i = 0, numInteriorRings = polygon->getNumInteriorRings(); i < numInteriorRings; ++i )
{
result |= simplifyOgrGeometry( polygon->getInteriorRing( i ), true );
}
if ( result ) polygon->flattenTo2D();
return result;
}
else
if ( wkbGeometryType == wkbMultiLineString || wkbGeometryType == wkbMultiPolygon )
{
OGRGeometryCollection* collection = ( OGRGeometryCollection* )geometry;
bool result = false;
for ( int i = 0, numGeometries = collection->getNumGeometries(); i < numGeometries; ++i )
{
result |= simplifyOgrGeometry( collection->getGeometryRef( i ), wkbGeometryType == wkbMultiPolygon );
}
if ( result ) collection->flattenTo2D();
return result;
}
return false;
}
