Merge pull request #40444 from pblottiere/geographic-extent-store

Geographic extent storing
qgis · Mar 10, 2021 · 3f5b165 · 3f5b165
2 parents 84b3cb1 + 1970df7
commit 3f5b165
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Showing 15 changed files with 249 additions and 42 deletions.
diff --git a/python/core/auto_generated/qgsmaplayer.sip.in b/python/core/auto_generated/qgsmaplayer.sip.in
@@ -503,6 +503,18 @@ Returns new instance of :py:class:`QgsMapLayerRenderer` that will be used for re
     virtual QgsRectangle extent() const;
 %Docstring
 Returns the extent of the layer.
+%End
+
+    QgsRectangle wgs84Extent( bool forceRecalculate = false ) const;
+%Docstring
+Returns the WGS84 extent (EPSG:4326) of the layer according to
+ReadFlag.FlagTrustLayerMetadata. If that flag is activated, then the
+WGS84 extent read in the qgs project is returned. Otherwise, the actual
+WGS84 extent is returned.
+
+:param forceRecalculate: True to return the current WGS84 extent whatever the read flags
+
+.. versionadded:: 3.20
 %End
 
     bool isValid() const;
@@ -1800,6 +1812,14 @@ Add error message
 Sets error message
 %End
 
+    void invalidateWgs84Extent();
+%Docstring
+Invalidates the WGS84 extent. If FlagTrustLayerMetadata is enabled,
+the extent is not invalidated because we want to trust metadata whatever
+happens.
+
+.. versionadded:: 3.20
+%End
 
 
 

diff --git a/python/core/auto_generated/qgsxmlutils.sip.in b/python/core/auto_generated/qgsxmlutils.sip.in
@@ -50,7 +50,16 @@ Encodes a distance unit to a DOM element.
 .. seealso:: :py:func:`readMapUnits`
 %End
 
-    static QDomElement writeRectangle( const QgsRectangle &rect, QDomDocument &doc );
+    static QDomElement writeRectangle( const QgsRectangle &rect, QDomDocument &doc, const QString &elementName = QStringLiteral( "extent" ) );
+%Docstring
+Encodes a rectangle to a DOM element.
+
+:param rect: rectangle to encode
+:param doc: DOM document
+:param elementName: name of the DOM element
+
+:return: element containing encoded rectangle
+%End
 
     static QDomElement writeVariant( const QVariant &value, QDomDocument &doc );
 %Docstring

diff --git a/src/core/annotations/qgsannotationlayer.cpp b/src/core/annotations/qgsannotationlayer.cpp
@@ -120,6 +120,7 @@ QgsRectangle QgsAnnotationLayer::extent() const
 void QgsAnnotationLayer::setTransformContext( const QgsCoordinateTransformContext &context )
 {
   mTransformContext = context;
+  invalidateWgs84Extent();
 }
 
 bool QgsAnnotationLayer::readXml( const QDomNode &layerNode, QgsReadWriteContext &context )

diff --git a/src/core/mesh/qgsmeshlayer.cpp b/src/core/mesh/qgsmeshlayer.cpp
@@ -539,6 +539,7 @@ void QgsMeshLayer::setTransformContext( const QgsCoordinateTransformContext &tra
 {
   if ( mDataProvider )
     mDataProvider->setTransformContext( transformContext );
+  invalidateWgs84Extent();
 }
 
 QgsMeshDatasetIndex QgsMeshLayer::datasetIndexAtTime( const QgsDateTimeRange &timeRange, int datasetGroupIndex ) const

diff --git a/src/core/pointcloud/qgspointcloudlayer.cpp b/src/core/pointcloud/qgspointcloudlayer.cpp
@@ -277,6 +277,7 @@ void QgsPointCloudLayer::setTransformContext( const QgsCoordinateTransformContex
 {
   if ( mDataProvider )
     mDataProvider->setTransformContext( transformContext );
+  invalidateWgs84Extent();
 }
 
 void QgsPointCloudLayer::setDataSource( const QString &dataSource, const QString &baseName, const QString &provider,

diff --git a/src/core/qgsmaplayer.cpp b/src/core/qgsmaplayer.cpp
@@ -56,6 +56,7 @@
 #include "qgsvectordataprovider.h"
 #include "qgsxmlutils.h"
 #include "qgsstringutils.h"
+#include "qgsmessagelog.h"
 #include "qgsmaplayertemporalproperties.h"
 #include "qgsmaplayerelevationproperties.h"
 
@@ -392,6 +393,14 @@ bool QgsMapLayer::readLayerXml( const QDomElement &layerElement, QgsReadWriteCon
   setRefreshOnNofifyMessage( layerElement.attribute( QStringLiteral( "refreshOnNotifyMessage" ), QString() ) );
   setRefreshOnNotifyEnabled( layerElement.attribute( QStringLiteral( "refreshOnNotifyEnabled" ), QStringLiteral( "0" ) ).toInt() );
 
+  // geographic extent is read only if necessary
+  if ( mReadFlags & QgsMapLayer::ReadFlag::FlagTrustLayerMetadata )
+  {
+    const QDomNode wgs84ExtentNode = layerElement.namedItem( QStringLiteral( "wgs84extent" ) );
+    if ( !wgs84ExtentNode.isNull() )
+      mWgs84Extent = QgsXmlUtils::readRectangle( wgs84ExtentNode.toElement() );
+  }
+
   return ! layerError;
 } // bool QgsMapLayer::readLayerXML
 
@@ -411,6 +420,7 @@ bool QgsMapLayer::writeLayerXml( QDomElement &layerElement, QDomDocument &docume
   if ( !extent().isNull() )
   {
     layerElement.appendChild( QgsXmlUtils::writeRectangle( mExtent, document ) );
+    layerElement.appendChild( QgsXmlUtils::writeRectangle( wgs84Extent( true ), document, QStringLiteral( "wgs84extent" ) ) );
   }
 
   layerElement.setAttribute( QStringLiteral( "autoRefreshTime" ), QString::number( mRefreshTimer->interval() ) );
@@ -1899,9 +1909,9 @@ void QgsMapLayer::emitStyleChanged()
   emit styleChanged();
 }
 
-void QgsMapLayer::setExtent( const QgsRectangle &r )
+void QgsMapLayer::setExtent( const QgsRectangle &extent )
 {
-  mExtent = r;
+  updateExtent( extent );
 }
 
 bool QgsMapLayer::isReadOnly() const
@@ -2001,3 +2011,50 @@ void QgsMapLayer::onNotified( const QString &message )
     emit dataChanged();
   }
 }
+
+QgsRectangle QgsMapLayer::wgs84Extent( bool forceRecalculate ) const
+{
+  QgsRectangle wgs84Extent;
+
+  if ( ! forceRecalculate && ! mWgs84Extent.isNull() )
+  {
+    wgs84Extent = mWgs84Extent;
+  }
+  else if ( ! mExtent.isNull() )
+  {
+    const QgsCoordinateTransform transformer { crs(), QgsCoordinateReferenceSystem::fromOgcWmsCrs( geoEpsgCrsAuthId() ), transformContext() };
+    try
+    {
+      wgs84Extent = transformer.transformBoundingBox( mExtent );
+    }
+    catch ( const QgsCsException &cse )
+    {
+      QgsMessageLog::logMessage( tr( "Error transforming extent: %1" ).arg( cse.what() ) );
+      wgs84Extent = QgsRectangle();
+    }
+  }
+  return wgs84Extent;
+}
+
+void QgsMapLayer::updateExtent( const QgsRectangle &extent ) const
+{
+  if ( extent == mExtent )
+    return;
+
+  mExtent = extent;
+
+  // do not update the wgs84 extent if we trust layer metadata
+  if ( mReadFlags & QgsMapLayer::ReadFlag::FlagTrustLayerMetadata )
+    return;
+
+  mWgs84Extent = wgs84Extent( true );
+}
+
+void QgsMapLayer::invalidateWgs84Extent()
+{
+  // do not update the wgs84 extent if we trust layer metadata
+  if ( mReadFlags & QgsMapLayer::ReadFlag::FlagTrustLayerMetadata )
+    return;
+
+  mWgs84Extent = QgsRectangle();
+}
diff --git a/src/core/qgsmaplayer.h b/src/core/qgsmaplayer.h
@@ -514,6 +514,16 @@ class CORE_EXPORT QgsMapLayer : public QObject
     //! Returns the extent of the layer.
     virtual QgsRectangle extent() const;
 
+    /**
+     * Returns the WGS84 extent (EPSG:4326) of the layer according to
+     * ReadFlag::FlagTrustLayerMetadata. If that flag is activated, then the
+     * WGS84 extent read in the qgs project is returned. Otherwise, the actual
+     * WGS84 extent is returned.
+     * \param forceRecalculate True to return the current WGS84 extent whatever the read flags
+     * \since QGIS 3.20
+     */
+    QgsRectangle wgs84Extent( bool forceRecalculate = false ) const;
+
     /**
      * Returns the status of the layer. An invalid layer is one which has a bad datasource
      * or other problem. Child classes set this flag when initialized.
@@ -1602,8 +1612,13 @@ class CORE_EXPORT QgsMapLayer : public QObject
     //! Sets error message
     void setError( const QgsError &error ) { mError = error;}
 
-    //! Extent of the layer
-    mutable QgsRectangle mExtent;
+    /**
+     * Invalidates the WGS84 extent. If FlagTrustLayerMetadata is enabled,
+     * the extent is not invalidated because we want to trust metadata whatever
+     * happens.
+     * \since QGIS 3.20
+     */
+    void invalidateWgs84Extent();
 
     //! Indicates if the layer is valid and can be drawn
     bool mValid = false;
@@ -1685,6 +1700,9 @@ class CORE_EXPORT QgsMapLayer : public QObject
                                bool &resultFlag, StyleCategories categories = AllStyleCategories );
     bool loadNamedPropertyFromDatabase( const QString &db, const QString &uri, QString &xml, QgsMapLayer::PropertyType type );
 
+    // const method because extents are mutable
+    void updateExtent( const QgsRectangle &extent ) const;
+
     /**
      * This method returns TRUE by default but can be overwritten to specify
      * that a certain layer is writable.
@@ -1742,6 +1760,12 @@ class CORE_EXPORT QgsMapLayer : public QObject
     //! Renderer for 3D views
     QgsAbstract3DRenderer *m3DRenderer = nullptr;
 
+    //! Extent of the layer
+    mutable QgsRectangle mExtent;
+
+    //! Extent of the layer in EPSG:4326
+    mutable QgsRectangle mWgs84Extent;
+
     /**
      * Stores the original XML properties of the layer when loaded from the project
      *
@@ -1751,6 +1775,8 @@ class CORE_EXPORT QgsMapLayer : public QObject
 
     //! To avoid firing multiple time repaintRequested signal on circular layer circular dependencies
     bool mRepaintRequestedFired = false;
+
+    friend class QgsVectorLayer;
 };
 
 Q_DECLARE_METATYPE( QgsMapLayer * )

diff --git a/src/core/qgspluginlayer.cpp b/src/core/qgspluginlayer.cpp
@@ -40,7 +40,7 @@ QString QgsPluginLayer::pluginLayerType()
 
 void QgsPluginLayer::setExtent( const QgsRectangle &extent )
 {
-  mExtent = extent;
+  QgsMapLayer::setExtent( extent );
   static_cast<QgsPluginLayerDataProvider *>( mDataProvider )->setExtent( extent );
 }
 

diff --git a/src/core/qgsxmlutils.cpp b/src/core/qgsxmlutils.cpp
@@ -78,7 +78,7 @@ QDomElement QgsXmlUtils::writeMapUnits( QgsUnitTypes::DistanceUnit units, QDomDo
   return unitsNode;
 }
 
-QDomElement QgsXmlUtils::writeRectangle( const QgsRectangle &rect, QDomDocument &doc )
+QDomElement QgsXmlUtils::writeRectangle( const QgsRectangle &rect, QDomDocument &doc, const QString &elementName )
 {
   QDomElement xMin = doc.createElement( QStringLiteral( "xmin" ) );
   QDomElement yMin = doc.createElement( QStringLiteral( "ymin" ) );
@@ -95,7 +95,7 @@ QDomElement QgsXmlUtils::writeRectangle( const QgsRectangle &rect, QDomDocument
   xMax.appendChild( xMaxText );
   yMax.appendChild( yMaxText );
 
-  QDomElement extentNode = doc.createElement( QStringLiteral( "extent" ) );
+  QDomElement extentNode = doc.createElement( elementName );
   extentNode.appendChild( xMin );
   extentNode.appendChild( yMin );
   extentNode.appendChild( xMax );

diff --git a/src/core/qgsxmlutils.h b/src/core/qgsxmlutils.h
@@ -59,7 +59,14 @@ class CORE_EXPORT QgsXmlUtils
      */
     static QDomElement writeMapUnits( QgsUnitTypes::DistanceUnit units, QDomDocument &doc );
 
-    static QDomElement writeRectangle( const QgsRectangle &rect, QDomDocument &doc );
+    /**
+     * Encodes a rectangle to a DOM element.
+     * \param rect rectangle to encode
+     * \param doc DOM document
+     * \param elementName name of the DOM element
+     * \returns element containing encoded rectangle
+     */
+    static QDomElement writeRectangle( const QgsRectangle &rect, QDomDocument &doc, const QString &elementName = QStringLiteral( "extent" ) );
 
     /**
      * Write a QVariant to a QDomElement.

diff --git a/src/core/raster/qgsrasterlayer.cpp b/src/core/raster/qgsrasterlayer.cpp
@@ -1759,6 +1759,7 @@ void QgsRasterLayer::setTransformContext( const QgsCoordinateTransformContext &t
 {
   if ( mDataProvider )
     mDataProvider->setTransformContext( transformContext );
+  invalidateWgs84Extent();
 }
 
 QStringList QgsRasterLayer::subLayers() const

diff --git a/src/core/vector/qgsvectorlayer.cpp b/src/core/vector/qgsvectorlayer.cpp
@@ -848,23 +848,20 @@ QgsRectangle QgsVectorLayer::extent() const
 
   if ( !mValidExtent && mLazyExtent && mDataProvider && !mDataProvider->hasMetadata() && mReadExtentFromXml && !mXmlExtent.isNull() )
   {
-    mExtent = mXmlExtent;
+    updateExtent( mXmlExtent );
     mValidExtent = true;
     mLazyExtent = false;
   }
 
   if ( !mValidExtent && mLazyExtent && mDataProvider && mDataProvider->isValid() )
   {
-    // get the extent
-    QgsRectangle mbr = mDataProvider->extent();
-
-    // show the extent
-    QgsDebugMsgLevel( QStringLiteral( "Extent of layer: %1" ).arg( mbr.toString() ), 3 );
     // store the extent
+    updateExtent( mDataProvider->extent() );
     mValidExtent = true;
-    mExtent = mbr;
-
     mLazyExtent = false;
+
+    // show the extent
+    QgsDebugMsgLevel( QStringLiteral( "Extent of layer: %1" ).arg( mExtent.toString() ), 3 );
   }
 
   if ( mValidExtent )
@@ -886,7 +883,7 @@ QgsRectangle QgsVectorLayer::extent() const
     // but only when there are some features already
     if ( mDataProvider->featureCount() != 0 )
     {
-      QgsRectangle r = mDataProvider->extent();
+      const QgsRectangle r = mDataProvider->extent();
       rect.combineExtentWith( r );
     }
 
@@ -897,7 +894,7 @@ QgsRectangle QgsVectorLayer::extent() const
       {
         if ( it->hasGeometry() )
         {
-          QgsRectangle r = it->geometry().boundingBox();
+          const QgsRectangle r = it->geometry().boundingBox();
           rect.combineExtentWith( r );
         }
       }
@@ -913,7 +910,7 @@ QgsRectangle QgsVectorLayer::extent() const
     {
       if ( fet.hasGeometry() && fet.geometry().type() != QgsWkbTypes::UnknownGeometry )
       {
-        QgsRectangle bb = fet.geometry().boundingBox();
+        const QgsRectangle bb = fet.geometry().boundingBox();
         rect.combineExtentWith( bb );
       }
     }
@@ -925,8 +922,8 @@ QgsRectangle QgsVectorLayer::extent() const
     rect = QgsRectangle(); // use rectangle with zero coordinates
   }
 
+  updateExtent( rect );
   mValidExtent = true;
-  mExtent = rect;
 
   // Send this (hopefully) up the chain to the map canvas
   emit recalculateExtents();

diff --git a/src/core/vectortile/qgsvectortilelayer.cpp b/src/core/vectortile/qgsvectortilelayer.cpp
@@ -344,6 +344,7 @@ bool QgsVectorTileLayer::writeSymbology( QDomNode &node, QDomDocument &doc, QStr
 void QgsVectorTileLayer::setTransformContext( const QgsCoordinateTransformContext &transformContext )
 {
   Q_UNUSED( transformContext )
+  invalidateWgs84Extent();
 }
 
 QString QgsVectorTileLayer::loadDefaultStyle( bool &resultFlag )