QgsVectorFileWriter map NaN to -DBL_MAX exporting to Shape

qgis · Nov 15, 2022 · 19da39f · 19da39f
1 parent dd47d4a
commit 19da39f
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Showing 9 changed files with 73 additions and 10 deletions.
diff --git a/python/core/auto_generated/geometry/qgsabstractgeometry.sip.in b/python/core/auto_generated/geometry/qgsabstractgeometry.sip.in
@@ -210,6 +210,7 @@ Sets the geometry from a WKT string.
     enum WkbFlag
     {
       FlagExportTrianglesAsPolygons,
+      FlagExportNanAsDoubleMin,
     };
     typedef QFlags<QgsAbstractGeometry::WkbFlag> WkbFlags;
 

diff --git a/src/core/geometry/qgsabstractgeometry.h b/src/core/geometry/qgsabstractgeometry.h
@@ -273,6 +273,7 @@ class CORE_EXPORT QgsAbstractGeometry
     enum WkbFlag
     {
       FlagExportTrianglesAsPolygons = 1 << 0, //!< Triangles should be exported as polygon geometries
+      FlagExportNanAsDoubleMin = 1 << 1, //!< Use -DOUBLE_MAX to represent NaN (since QGIS 3.30)
     };
     Q_DECLARE_FLAGS( WkbFlags, WkbFlag )
 

diff --git a/src/core/geometry/qgscircularstring.cpp b/src/core/geometry/qgscircularstring.cpp
@@ -517,7 +517,7 @@ QByteArray QgsCircularString::asWkb( WkbFlags flags ) const
   wkb << static_cast<quint32>( wkbType() );
   QgsPointSequence pts;
   points( pts );
-  QgsGeometryUtils::pointsToWKB( wkb, pts, is3D(), isMeasure() );
+  QgsGeometryUtils::pointsToWKB( wkb, pts, is3D(), isMeasure(), flags );
   return wkbArray;
 }
 

diff --git a/src/core/geometry/qgsgeometryutils.cpp b/src/core/geometry/qgsgeometryutils.cpp
@@ -1216,19 +1216,29 @@ QgsPointSequence QgsGeometryUtils::pointsFromWKT( const QString &wktCoordinateLi
   return points;
 }
 
-void QgsGeometryUtils::pointsToWKB( QgsWkbPtr &wkb, const QgsPointSequence &points, bool is3D, bool isMeasure )
+void QgsGeometryUtils::pointsToWKB( QgsWkbPtr &wkb, const QgsPointSequence &points, bool is3D, bool isMeasure, QgsAbstractGeometry::WkbFlags flags )
 {
   wkb << static_cast<quint32>( points.size() );
   for ( const QgsPoint &point : points )
   {
     wkb << point.x() << point.y();
     if ( is3D )
     {
-      wkb << point.z();
+      double z = point.z();
+      if ( flags & QgsAbstractGeometry::FlagExportNanAsDoubleMin
+           && std::isnan( z ) )
+        z = -DBL_MAX;
+
+      wkb << z;
     }
     if ( isMeasure )
     {
-      wkb << point.m();
+      double m = point.m();
+      if ( flags & QgsAbstractGeometry::FlagExportNanAsDoubleMin
+           && std::isnan( m ) )
+        m = -DBL_MAX;
+
+      wkb << m;
     }
   }
 }

diff --git a/src/core/geometry/qgsgeometryutils.h b/src/core/geometry/qgsgeometryutils.h
@@ -455,7 +455,7 @@ class CORE_EXPORT QgsGeometryUtils
      * Returns a LinearRing { uint32 numPoints; Point points[numPoints]; }
      * \note not available in Python bindings
      */
-    static void pointsToWKB( QgsWkbPtr &wkb, const QgsPointSequence &points, bool is3D, bool isMeasure ) SIP_SKIP;
+    static void pointsToWKB( QgsWkbPtr &wkb, const QgsPointSequence &points, bool is3D, bool isMeasure, QgsAbstractGeometry::WkbFlags flags ) SIP_SKIP;
 
     /**
      * Returns a WKT coordinate list

diff --git a/src/core/geometry/qgslinestring.cpp b/src/core/geometry/qgslinestring.cpp
@@ -703,7 +703,7 @@ QByteArray QgsLineString::asWkb( WkbFlags flags ) const
   wkb << static_cast<quint32>( wkbType() );
   QgsPointSequence pts;
   points( pts );
-  QgsGeometryUtils::pointsToWKB( wkb, pts, is3D(), isMeasure() );
+  QgsGeometryUtils::pointsToWKB( wkb, pts, is3D(), isMeasure(), flags );
   return wkbArray;
 }
 

diff --git a/src/core/geometry/qgspolygon.cpp b/src/core/geometry/qgspolygon.cpp
@@ -173,13 +173,13 @@ QByteArray QgsPolygon::asWkb( QgsAbstractGeometry::WkbFlags flags ) const
   {
     QgsPointSequence pts;
     mExteriorRing->points( pts );
-    QgsGeometryUtils::pointsToWKB( wkb, pts, mExteriorRing->is3D(), mExteriorRing->isMeasure() );
+    QgsGeometryUtils::pointsToWKB( wkb, pts, mExteriorRing->is3D(), mExteriorRing->isMeasure(), flags );
   }
   for ( const QgsCurve *curve : mInteriorRings )
   {
     QgsPointSequence pts;
     curve->points( pts );
-    QgsGeometryUtils::pointsToWKB( wkb, pts, curve->is3D(), curve->isMeasure() );
+    QgsGeometryUtils::pointsToWKB( wkb, pts, curve->is3D(), curve->isMeasure(), flags );
   }
 
   return wkbArray;

diff --git a/src/core/qgsvectorfilewriter.cpp b/src/core/qgsvectorfilewriter.cpp
@@ -2840,7 +2840,11 @@ gdal::ogr_feature_unique_ptr QgsVectorFileWriter::createFeature( const QgsFeatur
       }
       else // wkb type matches
       {
-        QByteArray wkb( geom.asWkb( QgsAbstractGeometry::FlagExportTrianglesAsPolygons ) );
+        QgsAbstractGeometry::WkbFlags wkbFlags = QgsAbstractGeometry::FlagExportTrianglesAsPolygons;
+        if ( mOgrDriverName == QLatin1String( "ESRI Shapefile" ) )
+          wkbFlags |= QgsAbstractGeometry::FlagExportNanAsDoubleMin;
+
+        QByteArray wkb( geom.asWkb( wkbFlags ) );
         OGRGeometryH ogrGeom = createEmptyGeometry( mWkbType );
         OGRErr err = OGR_G_ImportFromWkb( ogrGeom, reinterpret_cast<unsigned char *>( const_cast<char *>( wkb.constData() ) ), wkb.length() );
         if ( err != OGRERR_NONE )

diff --git a/tests/src/core/testqgsvectorfilewriter.cpp b/tests/src/core/testqgsvectorfilewriter.cpp
@@ -110,7 +110,8 @@ class TestQgsVectorFileWriter: public QObject
     void testExportToGpxMultiLineStringForceRoute();
     //! Test export using custom field names
     void testExportCustomFieldNames();
-
+    //! Test export to shape with NaN values for Z
+    void testExportToShapeNanValuesForZ();
   private:
     // a little util fn used by all tests
     bool cleanupFile( QString fileBase );
@@ -704,5 +705,51 @@ void TestQgsVectorFileWriter::testExportCustomFieldNames()
   QCOMPARE( details.outputFields.at( 1 ).name(), "customfieldname" );
 }
 
+void TestQgsVectorFileWriter::testExportToShapeNanValuesForZ()
+{
+  //
+  // Remove old copies that may be lying around
+  //
+  QString myFileName = QStringLiteral( "/testln.shp" );
+  myFileName = QDir::tempPath() + myFileName;
+  QVERIFY( QgsVectorFileWriter::deleteShapeFile( myFileName ) );
+
+  QgsVectorFileWriter::SaveVectorOptions saveOptions;
+  saveOptions.fileEncoding = mEncoding;
+  std::unique_ptr< QgsVectorFileWriter > writer( QgsVectorFileWriter::create( myFileName, mFields, QgsWkbTypes::LineStringZ, mCRS, QgsCoordinateTransformContext(), saveOptions ) );
+  //
+  // Create a feature
+  //
+  QgsLineString *ls = new QgsLineString();
+  ls->setPoints( QgsPointSequence() << QgsPoint( mPoint1 )
+                 << QgsPoint( mPoint2 )
+                 << QgsPoint( mPoint3 ) );
+  ls->setZAt( 1, std::numeric_limits<double>::quiet_NaN() );
+  const QgsGeometry mypLineGeometry( ls );
+  QgsFeature myFeature;
+  myFeature.setGeometry( mypLineGeometry );
+  myFeature.initAttributes( 1 );
+  myFeature.setAttribute( 0, "HelloWorld" );
+  //
+  // Write the feature to the filewriter
+  // and check for errors
+  //
+  QVERIFY( writer->addFeature( myFeature ) );
+  mError = writer->hasError();
+  if ( mError == QgsVectorFileWriter::ErrDriverNotFound )
+  {
+    std::cout << "Driver not found error" << std::endl;
+  }
+  else if ( mError == QgsVectorFileWriter::ErrCreateDataSource )
+  {
+    std::cout << "Create data source error" << std::endl;
+  }
+  else if ( mError == QgsVectorFileWriter::ErrCreateLayer )
+  {
+    std::cout << "Create layer error" << std::endl;
+  }
+  QVERIFY( mError == QgsVectorFileWriter::NoError );
+}
+
 QGSTEST_MAIN( TestQgsVectorFileWriter )
 #include "testqgsvectorfilewriter.moc"