Mesh Render Extent Settings

This brings to renderer for Mesh Contours option to set renderer Min Max based on extent (specific canvas, changing canvas) in the same way as renderers for Raster Layer.

python/PyQt6/core/auto_additions/qgis.py

@@ -11041,6 +11041,34 @@
 """
 # --
 Qgis.MouseHandlesAction.baseClass = Qgis
+# monkey patching scoped based enum
+Qgis.MeshRangeLimit.NotSet.__doc__ = "User defined"
+Qgis.MeshRangeLimit.MinimumMaximum.__doc__ = "Real min-max values"
+Qgis.MeshRangeLimit.__doc__ = """Describes the limits used to compute mesh ranges (min/max values).
+
+.. versionadded:: 3.42
+
+* ``NotSet``: User defined
+* ``MinimumMaximum``: Real min-max values
+
+"""
+# --
+Qgis.MeshRangeLimit.baseClass = Qgis
+# monkey patching scoped based enum
+Qgis.MeshRangeExtent.WholeMesh.__doc__ = "Whole mesh is used to compute statistics"
+Qgis.MeshRangeExtent.FixedCanvas.__doc__ = "Current extent of the canvas (at the time of computation) is used to compute statistics"
+Qgis.MeshRangeExtent.UpdatedCanvas.__doc__ = "Constantly updated extent of the canvas is used to compute statistics"
+Qgis.MeshRangeExtent.__doc__ = """Describes the extent used to compute mesh ranges (min/max values).
+
+.. versionadded:: 3.42
+
+* ``WholeMesh``: Whole mesh is used to compute statistics
+* ``FixedCanvas``: Current extent of the canvas (at the time of computation) is used to compute statistics
+* ``UpdatedCanvas``: Constantly updated extent of the canvas is used to compute statistics
+
+"""
+# --
+Qgis.MeshRangeExtent.baseClass = Qgis
 try:
     Qgis.__attribute_docs__ = {'QGIS_DEV_VERSION': 'The development version', 'DEFAULT_SEARCH_RADIUS_MM': 'Identify search radius in mm', 'DEFAULT_MAPTOPIXEL_THRESHOLD': 'Default threshold between map coordinates and device coordinates for map2pixel simplification', 'DEFAULT_HIGHLIGHT_COLOR': 'Default highlight color.  The transparency is expected to only be applied to polygon\nfill. Lines and outlines are rendered opaque.', 'DEFAULT_HIGHLIGHT_BUFFER_MM': 'Default highlight buffer in mm.', 'DEFAULT_HIGHLIGHT_MIN_WIDTH_MM': 'Default highlight line/stroke minimum width in mm.', 'SCALE_PRECISION': 'Fudge factor used to compare two scales. The code is often going from scale to scale\ndenominator. So it looses precision and, when a limit is inclusive, can lead to errors.\nTo avoid that, use this factor instead of using <= or >=.\n\n.. deprecated:: 3.40\n\n   No longer used by QGIS and will be removed in QGIS 4.0.', 'DEFAULT_Z_COORDINATE': 'Default Z coordinate value.\nThis value have to be assigned to the Z coordinate for the vertex.', 'DEFAULT_M_COORDINATE': 'Default M coordinate value.\nThis value have to be assigned to the M coordinate for the vertex.\n\n.. versionadded:: 3.20', 'UI_SCALE_FACTOR': 'UI scaling factor. This should be applied to all widget sizes obtained from font metrics,\nto account for differences in the default font sizes across different platforms.', 'DEFAULT_SNAP_TOLERANCE': 'Default snapping distance tolerance.', 'DEFAULT_SNAP_UNITS': 'Default snapping distance units.'}
     Qgis.version = staticmethod(Qgis.version)

python/PyQt6/core/auto_generated/mesh/qgsmeshlayer.sip.in

@@ -914,6 +914,27 @@ Access to labeling configuration. May be ``None`` if labeling is not used.
 Sets labeling configuration. Takes ownership of the object.
 
 .. versionadded:: 3.36
+%End
+
+    bool minimumMaximumActiveScalarDataset( const QgsRectangle &extent, const QgsMeshDatasetIndex &datasetIndex, double &min /Out/, double &max /Out/ );
+%Docstring
+Extracts minimum and maximum value for active scalar dataset on mesh faces.
+
+:param extent: extent in which intersecting faces are searched for
+:param datasetIndex: index for which dataset the values should be extracted
+
+:return: - ``True`` if values were extracted
+         - min: minimal value
+         - max: maximal value
+
+.. versionadded:: 3.42
+%End
+
+    QgsMeshDatasetIndex activeScalarDatasetIndex( QgsRenderContext &rendererContext );
+%Docstring
+Returns current active scalar dataset index for current renderer context.
+
+.. versionadded:: 3.42
 %End
 
     bool datasetsPathUnique( const QString &path );

python/PyQt6/core/auto_generated/mesh/qgsmeshrenderersettings.sip.in

@@ -178,6 +178,34 @@ Returns the stroke width unit used to render edges scalar dataset
 Sets the stroke width unit used to render edges scalar dataset
 
 .. versionadded:: 3.14
+%End
+
+    void setLimits( Qgis::MeshRangeLimit limits );
+%Docstring
+Sets the range limits type for minimum maximum calculation
+
+.. versionadded:: 3.42
+%End
+
+    Qgis::MeshRangeLimit limits() const;
+%Docstring
+Returns the range limits type for minimum maximum calculation
+
+.. versionadded:: 3.42
+%End
+
+    void setExtent( Qgis::MeshRangeExtent extent );
+%Docstring
+Sets the mesh extent for minimum maximum calculation
+
+.. versionadded:: 3.42
+%End
+
+    Qgis::MeshRangeExtent extent() const;
+%Docstring
+Returns the mesh extent for minimum maximum calculation
+
+.. versionadded:: 3.42
 %End
 
     QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context = QgsReadWriteContext() ) const;

python/PyQt6/core/auto_generated/qgis.sip.in

@@ -3226,6 +3226,19 @@ The development version
       NoAction
     };
 
+    enum class MeshRangeLimit /BaseType=IntEnum/
+    {
+      NotSet,
+      MinimumMaximum,
+    };
+
+    enum class MeshRangeExtent /BaseType=IntEnum/
+    {
+      WholeMesh,
+      FixedCanvas,
+      UpdatedCanvas,
+    };
+
     static const double DEFAULT_SEARCH_RADIUS_MM;
 
     static const float DEFAULT_MAPTOPIXEL_THRESHOLD;

python/core/auto_additions/qgis.py

@@ -10951,6 +10951,34 @@
 """
 # --
 Qgis.MouseHandlesAction.baseClass = Qgis
+# monkey patching scoped based enum
+Qgis.MeshRangeLimit.NotSet.__doc__ = "User defined"
+Qgis.MeshRangeLimit.MinimumMaximum.__doc__ = "Real min-max values"
+Qgis.MeshRangeLimit.__doc__ = """Describes the limits used to compute mesh ranges (min/max values).
+
+.. versionadded:: 3.42
+
+* ``NotSet``: User defined
+* ``MinimumMaximum``: Real min-max values
+
+"""
+# --
+Qgis.MeshRangeLimit.baseClass = Qgis
+# monkey patching scoped based enum
+Qgis.MeshRangeExtent.WholeMesh.__doc__ = "Whole mesh is used to compute statistics"
+Qgis.MeshRangeExtent.FixedCanvas.__doc__ = "Current extent of the canvas (at the time of computation) is used to compute statistics"
+Qgis.MeshRangeExtent.UpdatedCanvas.__doc__ = "Constantly updated extent of the canvas is used to compute statistics"
+Qgis.MeshRangeExtent.__doc__ = """Describes the extent used to compute mesh ranges (min/max values).
+
+.. versionadded:: 3.42
+
+* ``WholeMesh``: Whole mesh is used to compute statistics
+* ``FixedCanvas``: Current extent of the canvas (at the time of computation) is used to compute statistics
+* ``UpdatedCanvas``: Constantly updated extent of the canvas is used to compute statistics
+
+"""
+# --
+Qgis.MeshRangeExtent.baseClass = Qgis
 from enum import Enum
 
 

python/core/auto_generated/mesh/qgsmeshlayer.sip.in

@@ -914,6 +914,27 @@ Access to labeling configuration. May be ``None`` if labeling is not used.
 Sets labeling configuration. Takes ownership of the object.
 
 .. versionadded:: 3.36
+%End
+
+    bool minimumMaximumActiveScalarDataset( const QgsRectangle &extent, const QgsMeshDatasetIndex &datasetIndex, double &min /Out/, double &max /Out/ );
+%Docstring
+Extracts minimum and maximum value for active scalar dataset on mesh faces.
+
+:param extent: extent in which intersecting faces are searched for
+:param datasetIndex: index for which dataset the values should be extracted
+
+:return: - ``True`` if values were extracted
+         - min: minimal value
+         - max: maximal value
+
+.. versionadded:: 3.42
+%End
+
+    QgsMeshDatasetIndex activeScalarDatasetIndex( QgsRenderContext &rendererContext );
+%Docstring
+Returns current active scalar dataset index for current renderer context.
+
+.. versionadded:: 3.42
 %End
 
     bool datasetsPathUnique( const QString &path );

python/core/auto_generated/mesh/qgsmeshrenderersettings.sip.in

@@ -178,6 +178,34 @@ Returns the stroke width unit used to render edges scalar dataset
 Sets the stroke width unit used to render edges scalar dataset
 
 .. versionadded:: 3.14
+%End
+
+    void setLimits( Qgis::MeshRangeLimit limits );
+%Docstring
+Sets the range limits type for minimum maximum calculation
+
+.. versionadded:: 3.42
+%End
+
+    Qgis::MeshRangeLimit limits() const;
+%Docstring
+Returns the range limits type for minimum maximum calculation
+
+.. versionadded:: 3.42
+%End
+
+    void setExtent( Qgis::MeshRangeExtent extent );
+%Docstring
+Sets the mesh extent for minimum maximum calculation
+
+.. versionadded:: 3.42
+%End
+
+    Qgis::MeshRangeExtent extent() const;
+%Docstring
+Returns the mesh extent for minimum maximum calculation
+
+.. versionadded:: 3.42
 %End
 
     QDomElement writeXml( QDomDocument &doc, const QgsReadWriteContext &context = QgsReadWriteContext() ) const;

python/core/auto_generated/qgis.sip.in

@@ -3226,6 +3226,19 @@ The development version
       NoAction
     };
 
+    enum class MeshRangeLimit
+    {
+      NotSet,
+      MinimumMaximum,
+    };
+
+    enum class MeshRangeExtent
+    {
+      WholeMesh,
+      FixedCanvas,
+      UpdatedCanvas,
+    };
+
     static const double DEFAULT_SEARCH_RADIUS_MM;
 
     static const float DEFAULT_MAPTOPIXEL_THRESHOLD;

src/app/qgisapp.cpp

@@ -17180,6 +17180,20 @@ void QgisApp::handleRenderedLayerStatistics() const
         rasterLayer->emitStyleChanged();
         emit rasterLayer->rendererChanged();
       }
+
+      QgsMeshLayer *meshLayer = qobject_cast<QgsMeshLayer *>( QgsProject::instance()->mapLayer( layerStatistics->layerId() ) );
+      if ( meshLayer )
+      {
+        QgsMeshRendererSettings rendererSettings = meshLayer->rendererSettings();
+        QgsMeshRendererScalarSettings scalarRendererSettings = rendererSettings.scalarSettings( rendererSettings.activeScalarDatasetGroup() );
+        scalarRendererSettings.setClassificationMinimumMaximum( layerStatistics->minimum( 0 ), layerStatistics->maximum( 0 ) );
+        rendererSettings.setScalarSettings( rendererSettings.activeScalarDatasetGroup(), scalarRendererSettings );
+        meshLayer->setRendererSettings( rendererSettings );
+
+        meshLayer->emitStyleChanged();
+        emit meshLayer->rendererChanged();
+        emit meshLayer->legendChanged();
+      }
     }
   }
 }

src/core/mesh/qgsmeshlayer.cpp

@@ -1688,6 +1688,95 @@ QgsMapLayerRenderer *QgsMeshLayer::createMapRenderer( QgsRenderContext &renderer
   return new QgsMeshLayerRenderer( this, rendererContext );
 }
 
+QgsMeshDatasetIndex QgsMeshLayer::activeScalarDatasetIndex( QgsRenderContext &rendererContext )
+{
+  if ( rendererContext.isTemporal() )
+    return activeScalarDatasetAtTime( rendererContext.temporalRange(), mRendererSettings.activeScalarDatasetGroup() );
+  else
+    return staticScalarDatasetIndex( mRendererSettings.activeScalarDatasetGroup() );
+
+  return QgsMeshDatasetIndex();
+}
+
+bool QgsMeshLayer::minimumMaximumActiveScalarDataset( const QgsRectangle &extent, const QgsMeshDatasetIndex &datasetIndex, double &min, double &max )
+{
+
+  if ( extent.isNull() || !this->extent().intersects( extent ) )
+    return false;
+
+  QgsTriangularMesh *tMesh = triangularMesh();
+
+  QVector<double> scalarDatasetValues;
+  const QgsMeshDatasetGroupMetadata metadata = datasetGroupMetadata( datasetIndex.group() );
+
+  if ( !metadata.isScalar() )
+  {
+    return false;
+  }
+
+  QgsMeshDatasetGroupMetadata::DataType scalarDataType = QgsMeshLayerUtils::datasetValuesType( metadata.dataType() );
+
+  if ( !datasetIndex.isValid() )
+  {
+    return false;
+  }
+
+  // populate scalar values
+  const int count = QgsMeshLayerUtils::datasetValuesCount( mNativeMesh.get(), scalarDataType );
+  const QgsMeshDataBlock vals = QgsMeshLayerUtils::datasetValues(
+                                  this,
+                                  datasetIndex,
+                                  0,
+                                  count );
+
+  if ( vals.isValid() )
+  {
+    // vals could be scalar or vectors, for contour rendering we want always magnitude
+    scalarDatasetValues = QgsMeshLayerUtils::calculateMagnitudes( vals );
+  }
+  else
+  {
+    scalarDatasetValues = QVector<double>( count, std::numeric_limits<double>::quiet_NaN() );
+  }
+
+  QList<int> intersectedFacesIndices = tMesh->faceIndexesForRectangle( extent );
+
+  if ( intersectedFacesIndices.isEmpty() )
+  {
+    return false;
+  }
+
+  min = std::numeric_limits<double>::max();
+  max = -std::numeric_limits<double>::max();
+
+  double value;
+
+  for ( int intersectedFaceIndex : intersectedFacesIndices )
+  {
+    QgsMeshFace face = tMesh->triangles().at( intersectedFaceIndex );
+
+    if ( metadata.dataType() == QgsMeshDatasetGroupMetadata::DataType::DataOnFaces || metadata.dataType() == QgsMeshDatasetGroupMetadata::DataType::DataOnVolumes )
+    {
+      value = scalarDatasetValues.at( tMesh->trianglesToNativeFaces().at( intersectedFaceIndex ) );
+      min = std::min( min, value );
+      max = std::max( max, value );
+    }
+    else if ( metadata.dataType() == QgsMeshDatasetGroupMetadata::DataType::DataOnVertices )
+    {
+      QgsMeshVertex vertex;
+
+      for ( int vertexIndex : face )
+      {
+        value = scalarDatasetValues.at( vertexIndex );
+        min = std::min( min, value );
+        max = std::max( max, value );
+      }
+    }
+  }
+
+  return true;
+}
+
 QgsAbstractProfileGenerator *QgsMeshLayer::createProfileGenerator( const QgsProfileRequest &request )
 {
   QGIS_PROTECT_QOBJECT_THREAD_ACCESS

src/core/mesh/qgsmeshlayer.h

@@ -942,6 +942,24 @@ class CORE_EXPORT QgsMeshLayer : public QgsMapLayer, public QgsAbstractProfileSo
      */
     void setLabeling( QgsAbstractMeshLayerLabeling *labeling SIP_TRANSFER );
 
+    /**
+     * Extracts minimum and maximum value for active scalar dataset on mesh faces.
+     * \param extent extent in which intersecting faces are searched for
+     * \param datasetIndex index for which dataset the values should be extracted
+     * \param min minimal value
+     * \param max maximal value
+     * \return TRUE if values were extracted
+     * \since QGIS 3.42
+     */
+    bool minimumMaximumActiveScalarDataset( const QgsRectangle &extent, const QgsMeshDatasetIndex &datasetIndex, double &min SIP_OUT, double &max SIP_OUT );
+
+    /**
+     * Returns current active scalar dataset index for current renderer context.
+     *
+     * \since QGIS 3.42
+     */
+    QgsMeshDatasetIndex activeScalarDatasetIndex( QgsRenderContext &rendererContext );
+
     /**
      * Checks whether that datasets path is already added to this mesh layer. Return TRUE if the
      * dataset path is not already added.