void TestQgsDistanceArea::collections()
{
//test measuring for collections
QgsDistanceArea myDa;
myDa.setSourceAuthId( "EPSG:4030" );
myDa.setEllipsoidalMode( true );
myDa.setEllipsoid( "WGS84" );
//collection of lines, should be sum of line length
QgsGeometry lines( QgsGeometryFactory::geomFromWkt( "GeometryCollection( LineString(0 36.53, 5.76 -48.16), LineString(0 25.54, 24.20 36.70) )" ) );
double result = myDa.measureLength( &lines );
QGSCOMPARENEAR( result, 12006159, 1 );
result = myDa.measureArea( &lines );
QVERIFY( qgsDoubleNear( result, 0 ) );
//collection of polygons
QgsGeometry polys( QgsGeometryFactory::geomFromWkt( "GeometryCollection( Polygon((0 36.53, 5.76 -48.16, 0 25.54, 0 36.53)), Polygon((10 20, 15 20, 15 10, 10 20)) )" ) );
result = myDa.measureArea( &polys );
QGSCOMPARENEAR( result, 670434859475LL, 1 );
result = myDa.measureLength( &polys );
QVERIFY( qgsDoubleNear( result, 0 ) );
//mixed collection
QgsGeometry mixed( QgsGeometryFactory::geomFromWkt( "GeometryCollection( LineString(0 36.53, 5.76 -48.16), LineString(0 25.54, 24.20 36.70), Polygon((0 36.53, 5.76 -48.16, 0 25.54, 0 36.53)), Polygon((10 20, 15 20, 15 10, 10 20)) )" ) );
//measure area specifically
result = myDa.measureArea( &mixed );
QGSCOMPARENEAR( result, 670434859475LL, 1 );
//measure length
result = myDa.measureLength( &mixed );
QGSCOMPARENEAR( result, 12006159, 1 );
}
QMap< QString, QString > QgsMapToolIdentify::featureDerivedAttributes( QgsFeature *feature, QgsMapLayer *layer, const QgsPoint& layerPoint )
{
// Calculate derived attributes and insert:
// measure distance or area depending on geometry type
QMap< QString, QString > derivedAttributes;
// init distance/area calculator
QString ellipsoid = QgsProject::instance()->readEntry( "Measure", "/Ellipsoid", GEO_NONE );
QgsDistanceArea calc;
calc.setEllipsoidalMode( mCanvas->hasCrsTransformEnabled() );
calc.setEllipsoid( ellipsoid );
calc.setSourceCrs( layer->crs().srsid() );
QgsWKBTypes::Type wkbType = QgsWKBTypes::NoGeometry;
QGis::GeometryType geometryType = QGis::NoGeometry;
QgsVertexId vId;
QgsPointV2 closestPoint;
if ( feature->constGeometry() )
{
geometryType = feature->constGeometry()->type();
wkbType = feature->constGeometry()->geometry()->wkbType();
//find closest vertex to clicked point
closestPoint = QgsGeometryUtils::closestVertex( *feature->constGeometry()->geometry(), QgsPointV2( layerPoint.x(), layerPoint.y() ), vId );
}
if ( QgsWKBTypes::isMultiType( wkbType ) )
{
QString str = QLocale::system().toString( static_cast<QgsGeometryCollectionV2*>( feature->constGeometry()->geometry() )->numGeometries() );
derivedAttributes.insert( tr( "Parts" ), str );
str = QLocale::system().toString( vId.part + 1 );
derivedAttributes.insert( tr( "Part number" ), str );
}
if ( geometryType == QGis::Line )
{
const QgsPolyline &pline = feature->constGeometry()->asPolyline();
double dist = calc.measureLength( feature->constGeometry() );
QGis::UnitType myDisplayUnits;
convertMeasurement( calc, dist, myDisplayUnits, false );
QString str = calc.textUnit( dist, 3, myDisplayUnits, false ); // dist and myDisplayUnits are out params
derivedAttributes.insert( tr( "Length" ), str );
str = QLocale::system().toString( pline.size() );
derivedAttributes.insert( tr( "Vertices" ), str );
//add details of closest vertex to identify point
closestVertexAttributes( *feature->constGeometry()->geometry(), vId, layer, derivedAttributes );
if ( QgsWKBTypes::flatType( wkbType ) == QgsWKBTypes::LineString )
{
// Add the start and end points in as derived attributes
QgsPoint pnt = mCanvas->mapSettings().layerToMapCoordinates( layer, pline.first() );
str = QLocale::system().toString( pnt.x(), 'g', 10 );
derivedAttributes.insert( tr( "firstX", "attributes get sorted; translation for lastX should be lexically larger than this one" ), str );
str = QLocale::system().toString( pnt.y(), 'g', 10 );
derivedAttributes.insert( tr( "firstY" ), str );
pnt = mCanvas->mapSettings().layerToMapCoordinates( layer, pline.last() );
str = QLocale::system().toString( pnt.x(), 'g', 10 );
derivedAttributes.insert( tr( "lastX", "attributes get sorted; translation for firstX should be lexically smaller than this one" ), str );
str = QLocale::system().toString( pnt.y(), 'g', 10 );
derivedAttributes.insert( tr( "lastY" ), str );
}
}
else if ( geometryType == QGis::Polygon )
{
double area = calc.measureArea( feature->constGeometry() );
double perimeter = calc.measurePerimeter( feature->constGeometry() );
QGis::UnitType myDisplayUnits;
convertMeasurement( calc, area, myDisplayUnits, true ); // area and myDisplayUnits are out params
QString str = calc.textUnit( area, 3, myDisplayUnits, true );
derivedAttributes.insert( tr( "Area" ), str );
convertMeasurement( calc, perimeter, myDisplayUnits, false ); // perimeter and myDisplayUnits are out params
str = calc.textUnit( perimeter, 3, myDisplayUnits, false );
derivedAttributes.insert( tr( "Perimeter" ), str );
str = QLocale::system().toString( feature->constGeometry()->geometry()->nCoordinates() );
derivedAttributes.insert( tr( "Vertices" ), str );
//add details of closest vertex to identify point
closestVertexAttributes( *feature->constGeometry()->geometry(), vId, layer, derivedAttributes );
}
else if ( geometryType == QGis::Point &&
QgsWKBTypes::flatType( wkbType ) == QgsWKBTypes::Point )
{
// Include the x and y coordinates of the point as a derived attribute
QgsPoint pnt = mCanvas->mapSettings().layerToMapCoordinates( layer, feature->constGeometry()->asPoint() );
QString str = QLocale::system().toString( pnt.x(), 'g', 10 );
derivedAttributes.insert( "X", str );
str = QLocale::system().toString( pnt.y(), 'g', 10 );
derivedAttributes.insert( "Y", str );
if ( QgsWKBTypes::hasZ( wkbType ) )
{
str = QLocale::system().toString( static_cast<QgsPointV2*>( feature->constGeometry()->geometry() )->z(), 'g', 10 );
derivedAttributes.insert( "Z", str );
}
if ( QgsWKBTypes::hasM( wkbType ) )
{
str = QLocale::system().toString( static_cast<QgsPointV2*>( feature->constGeometry()->geometry() )->m(), 'g', 10 );
derivedAttributes.insert( "M", str );
}
}
return derivedAttributes;
}
QMap< QString, QString > QgsMapToolIdentify::featureDerivedAttributes( QgsFeature *feature, QgsMapLayer *layer, const QgsPoint& layerPoint )
{
// Calculate derived attributes and insert:
// measure distance or area depending on geometry type
QMap< QString, QString > derivedAttributes;
// init distance/area calculator
QString ellipsoid = QgsProject::instance()->ellipsoid();
QgsDistanceArea calc;
calc.setEllipsoidalMode( mCanvas->hasCrsTransformEnabled() );
calc.setEllipsoid( ellipsoid );
calc.setSourceCrs( layer->crs().srsid() );
QgsWkbTypes::Type wkbType = QgsWkbTypes::NoGeometry;
QgsWkbTypes::GeometryType geometryType = QgsWkbTypes::NullGeometry;
QgsVertexId vId;
QgsPointV2 closestPoint;
if ( feature->hasGeometry() )
{
geometryType = feature->geometry().type();
wkbType = feature->geometry().geometry()->wkbType();
//find closest vertex to clicked point
closestPoint = QgsGeometryUtils::closestVertex( *feature->geometry().geometry(), QgsPointV2( layerPoint.x(), layerPoint.y() ), vId );
}
if ( QgsWkbTypes::isMultiType( wkbType ) )
{
QString str = QLocale::system().toString( static_cast<const QgsGeometryCollection*>( feature->geometry().geometry() )->numGeometries() );
derivedAttributes.insert( tr( "Parts" ), str );
str = QLocale::system().toString( vId.part + 1 );
derivedAttributes.insert( tr( "Part number" ), str );
}
if ( geometryType == QgsWkbTypes::LineGeometry )
{
double dist = calc.measureLength( feature->geometry() );
dist = calc.convertLengthMeasurement( dist, displayDistanceUnits() );
QString str = formatDistance( dist );
derivedAttributes.insert( tr( "Length" ), str );
const QgsCurve* curve = dynamic_cast< const QgsCurve* >( feature->geometry().geometry() );
if ( curve )
{
str = QLocale::system().toString( curve->nCoordinates() );
derivedAttributes.insert( tr( "Vertices" ), str );
//add details of closest vertex to identify point
closestVertexAttributes( *curve, vId, layer, derivedAttributes );
// Add the start and end points in as derived attributes
QgsPoint pnt = mCanvas->mapSettings().layerToMapCoordinates( layer, QgsPoint( curve->startPoint().x(), curve->startPoint().y() ) );
str = formatXCoordinate( pnt );
derivedAttributes.insert( tr( "firstX", "attributes get sorted; translation for lastX should be lexically larger than this one" ), str );
str = formatYCoordinate( pnt );
derivedAttributes.insert( tr( "firstY" ), str );
pnt = mCanvas->mapSettings().layerToMapCoordinates( layer, QgsPoint( curve->endPoint().x(), curve->endPoint().y() ) );
str = formatXCoordinate( pnt );
derivedAttributes.insert( tr( "lastX", "attributes get sorted; translation for firstX should be lexically smaller than this one" ), str );
str = formatYCoordinate( pnt );
derivedAttributes.insert( tr( "lastY" ), str );
}
}
else if ( geometryType == QgsWkbTypes::PolygonGeometry )
{
double area = calc.measureArea( feature->geometry() );
area = calc.convertAreaMeasurement( area, displayAreaUnits() );
QString str = formatArea( area );
derivedAttributes.insert( tr( "Area" ), str );
double perimeter = calc.measurePerimeter( feature->geometry() );
perimeter = calc.convertLengthMeasurement( perimeter, displayDistanceUnits() );
str = formatDistance( perimeter );
derivedAttributes.insert( tr( "Perimeter" ), str );
str = QLocale::system().toString( feature->geometry().geometry()->nCoordinates() );
derivedAttributes.insert( tr( "Vertices" ), str );
//add details of closest vertex to identify point
closestVertexAttributes( *feature->geometry().geometry(), vId, layer, derivedAttributes );
}
else if ( geometryType == QgsWkbTypes::PointGeometry &&
QgsWkbTypes::flatType( wkbType ) == QgsWkbTypes::Point )
{
// Include the x and y coordinates of the point as a derived attribute
QgsPoint pnt = mCanvas->mapSettings().layerToMapCoordinates( layer, feature->geometry().asPoint() );
QString str = formatXCoordinate( pnt );
derivedAttributes.insert( "X", str );
str = formatYCoordinate( pnt );
derivedAttributes.insert( "Y", str );
if ( QgsWkbTypes::hasZ( wkbType ) )
{
str = QLocale::system().toString( static_cast<const QgsPointV2*>( feature->geometry().geometry() )->z(), 'g', 10 );
derivedAttributes.insert( "Z", str );
}
if ( QgsWkbTypes::hasM( wkbType ) )
{
str = QLocale::system().toString( static_cast<const QgsPointV2*>( feature->geometry().geometry() )->m(), 'g', 10 );
derivedAttributes.insert( "M", str );
}
}
return derivedAttributes;
}
int QgsTransectSample::createSample( QProgressDialog* pd )
{
Q_UNUSED( pd );
if ( !mStrataLayer || !mStrataLayer->isValid() )
{
return 1;
}
if ( !mBaselineLayer || !mBaselineLayer->isValid() )
{
return 2;
}
//stratum id is not necessarily an integer
QVariant::Type stratumIdType = QVariant::Int;
if ( !mStrataIdAttribute.isEmpty() )
{
stratumIdType = mStrataLayer->fields().field( mStrataIdAttribute ).type();
}
//create vector file writers for output
QgsFields outputPointFields;
outputPointFields.append( QgsField( "id", stratumIdType ) );
outputPointFields.append( QgsField( "station_id", QVariant::Int ) );
outputPointFields.append( QgsField( "stratum_id", stratumIdType ) );
outputPointFields.append( QgsField( "station_code", QVariant::String ) );
outputPointFields.append( QgsField( "start_lat", QVariant::Double ) );
outputPointFields.append( QgsField( "start_long", QVariant::Double ) );
QgsVectorFileWriter outputPointWriter( mOutputPointLayer, "utf-8", outputPointFields, QgsWkbTypes::Point,
mStrataLayer->crs() );
if ( outputPointWriter.hasError() != QgsVectorFileWriter::NoError )
{
return 3;
}
outputPointFields.append( QgsField( "bearing", QVariant::Double ) ); //add bearing attribute for lines
QgsVectorFileWriter outputLineWriter( mOutputLineLayer, "utf-8", outputPointFields, QgsWkbTypes::LineString,
mStrataLayer->crs() );
if ( outputLineWriter.hasError() != QgsVectorFileWriter::NoError )
{
return 4;
}
QgsFields usedBaselineFields;
usedBaselineFields.append( QgsField( "stratum_id", stratumIdType ) );
usedBaselineFields.append( QgsField( "ok", QVariant::String ) );
QgsVectorFileWriter usedBaselineWriter( mUsedBaselineLayer, "utf-8", usedBaselineFields, QgsWkbTypes::LineString,
mStrataLayer->crs() );
if ( usedBaselineWriter.hasError() != QgsVectorFileWriter::NoError )
{
return 5;
}
//debug: write clipped buffer bounds with stratum id to same directory as out_point
QFileInfo outputPointInfo( mOutputPointLayer );
QString bufferClipLineOutput = outputPointInfo.absolutePath() + "/out_buffer_clip_line.shp";
QgsFields bufferClipLineFields;
bufferClipLineFields.append( QgsField( "id", stratumIdType ) );
QgsVectorFileWriter bufferClipLineWriter( bufferClipLineOutput, "utf-8", bufferClipLineFields, QgsWkbTypes::LineString, mStrataLayer->crs() );
//configure distanceArea depending on minDistance units and output CRS
QgsDistanceArea distanceArea;
distanceArea.setSourceCrs( mStrataLayer->crs().srsid() );
if ( mMinDistanceUnits == Meters )
{
distanceArea.setEllipsoidalMode( true );
}
else
{
distanceArea.setEllipsoidalMode( false );
}
//possibility to transform output points to lat/long
QgsCoordinateTransform toLatLongTransform( mStrataLayer->crs(), QgsCoordinateReferenceSystem( 4326, QgsCoordinateReferenceSystem::EpsgCrsId ) );
//init random number generator
mt_srand( QTime::currentTime().msec() );
QgsFeatureRequest fr;
fr.setSubsetOfAttributes( QStringList() << mStrataIdAttribute << mMinDistanceAttribute << mNPointsAttribute, mStrataLayer->fields() );
QgsFeatureIterator strataIt = mStrataLayer->getFeatures( fr );
QgsFeature fet;
int nTotalTransects = 0;
int nFeatures = 0;
if ( pd )
{
pd->setMaximum( mStrataLayer->featureCount() );
}
while ( strataIt.nextFeature( fet ) )
{
if ( pd )
{
pd->setValue( nFeatures );
}
if ( pd && pd->wasCanceled() )
{
break;
}
if ( !fet.hasGeometry() )
{
continue;
}
QgsGeometry strataGeom = fet.geometry();
//find baseline for strata
QVariant strataId = fet.attribute( mStrataIdAttribute );
QgsGeometry baselineGeom = findBaselineGeometry( strataId.isValid() ? strataId : -1 );
if ( baselineGeom.isEmpty() )
{
continue;
}
double minDistance = fet.attribute( mMinDistanceAttribute ).toDouble();
double minDistanceLayerUnits = minDistance;
//if minDistance is in meters and the data in degrees, we need to apply a rough conversion for the buffer distance
double bufferDist = bufferDistance( minDistance );
if ( mMinDistanceUnits == Meters && mStrataLayer->crs().mapUnits() == QgsUnitTypes::DistanceDegrees )
{
minDistanceLayerUnits = minDistance / 111319.9;
}
QgsGeometry clippedBaseline = strataGeom.intersection( baselineGeom );
if ( !clippedBaseline || clippedBaseline.wkbType() == QgsWkbTypes::Unknown )
{
continue;
}
QgsGeometry* bufferLineClipped = clipBufferLine( strataGeom, &clippedBaseline, bufferDist );
if ( !bufferLineClipped )
{
continue;
}
//save clipped baseline to file
QgsFeature blFeature( usedBaselineFields );
blFeature.setGeometry( clippedBaseline );
blFeature.setAttribute( "stratum_id", strataId );
blFeature.setAttribute( "ok", "f" );
usedBaselineWriter.addFeature( blFeature );
//start loop to create random points along the baseline
int nTransects = fet.attribute( mNPointsAttribute ).toInt();
int nCreatedTransects = 0;
int nIterations = 0;
int nMaxIterations = nTransects * 50;
QgsSpatialIndex sIndex; //to check minimum distance
QMap< QgsFeatureId, QgsGeometry > lineFeatureMap;
while ( nCreatedTransects < nTransects && nIterations < nMaxIterations )
{
double randomPosition = (( double )mt_rand() / MD_RAND_MAX ) * clippedBaseline.length();
QgsGeometry samplePoint = clippedBaseline.interpolate( randomPosition );
++nIterations;
if ( samplePoint.isEmpty() )
{
continue;
}
QgsPoint sampleQgsPoint = samplePoint.asPoint();
QgsPoint latLongSamplePoint = toLatLongTransform.transform( sampleQgsPoint );
QgsFeature samplePointFeature( outputPointFields );
samplePointFeature.setGeometry( samplePoint );
samplePointFeature.setAttribute( "id", nTotalTransects + 1 );
samplePointFeature.setAttribute( "station_id", nCreatedTransects + 1 );
samplePointFeature.setAttribute( "stratum_id", strataId );
samplePointFeature.setAttribute( "station_code", strataId.toString() + '_' + QString::number( nCreatedTransects + 1 ) );
samplePointFeature.setAttribute( "start_lat", latLongSamplePoint.y() );
samplePointFeature.setAttribute( "start_long", latLongSamplePoint.x() );
//find closest point on clipped buffer line
QgsPoint minDistPoint;
int afterVertex;
if ( bufferLineClipped->closestSegmentWithContext( sampleQgsPoint, minDistPoint, afterVertex ) < 0 )
{
continue;
}
//bearing between sample point and min dist point (transect direction)
double bearing = distanceArea.bearing( sampleQgsPoint, minDistPoint ) / M_PI * 180.0;
QgsPoint ptFarAway( sampleQgsPoint.x() + ( minDistPoint.x() - sampleQgsPoint.x() ) * 1000000,
sampleQgsPoint.y() + ( minDistPoint.y() - sampleQgsPoint.y() ) * 1000000 );
QgsPolyline lineFarAway;
lineFarAway << sampleQgsPoint << ptFarAway;
QgsGeometry lineFarAwayGeom = QgsGeometry::fromPolyline( lineFarAway );
QgsGeometry lineClipStratum = lineFarAwayGeom.intersection( strataGeom );
if ( lineClipStratum.isEmpty() )
{
continue;
}
//cancel if distance between sample point and line is too large (line does not start at point
if ( lineClipStratum.distance( samplePoint ) > 0.000001 )
{
continue;
}
//if lineClipStratum is a multiline, take the part line closest to sampleQgsPoint
if ( lineClipStratum.wkbType() == QgsWkbTypes::MultiLineString
|| lineClipStratum.wkbType() == QgsWkbTypes::MultiLineString25D )
{
QgsGeometry singleLine = closestMultilineElement( sampleQgsPoint, lineClipStratum );
if ( !singleLine.isEmpty() )
{
lineClipStratum = singleLine;
}
}
//cancel if length of lineClipStratum is too small
double transectLength = distanceArea.measureLength( lineClipStratum );
if ( transectLength < mMinTransectLength )
{
continue;
}
//search closest existing profile. Cancel if dist < minDist
if ( otherTransectWithinDistance( lineClipStratum, minDistanceLayerUnits, minDistance, sIndex, lineFeatureMap, distanceArea ) )
{
continue;
}
QgsFeatureId fid( nCreatedTransects );
QgsFeature sampleLineFeature( outputPointFields, fid );
sampleLineFeature.setGeometry( lineClipStratum );
sampleLineFeature.setAttribute( "id", nTotalTransects + 1 );
sampleLineFeature.setAttribute( "station_id", nCreatedTransects + 1 );
sampleLineFeature.setAttribute( "stratum_id", strataId );
sampleLineFeature.setAttribute( "station_code", strataId.toString() + '_' + QString::number( nCreatedTransects + 1 ) );
sampleLineFeature.setAttribute( "start_lat", latLongSamplePoint.y() );
sampleLineFeature.setAttribute( "start_long", latLongSamplePoint.x() );
sampleLineFeature.setAttribute( "bearing", bearing );
outputLineWriter.addFeature( sampleLineFeature );
//add point to file writer here.
//It can only be written if the corresponding transect has been as well
outputPointWriter.addFeature( samplePointFeature );
sIndex.insertFeature( sampleLineFeature );
lineFeatureMap.insert( fid, lineClipStratum );
++nTotalTransects;
++nCreatedTransects;
}
QgsFeature bufferClipFeature;
bufferClipFeature.setGeometry( *bufferLineClipped );
delete bufferLineClipped;
bufferClipFeature.setAttribute( "id", strataId );
bufferClipLineWriter.addFeature( bufferClipFeature );
//delete bufferLineClipped;
++nFeatures;
}
if ( pd )
{
pd->setValue( mStrataLayer->featureCount() );
}
return 0;
}