format code and add documentation

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

@@ -197,6 +197,8 @@ Interpolates the value on the given point from given dataset.
 
 Returns NaN for NaN values, for values outside range or when
 triangular mesh is not yet initialized on given point
+
+.. versionadded:: 3.4
 %End
 
   signals:

src/core/mesh/qgsmeshlayer.cpp

@@ -195,8 +195,8 @@ QgsMeshDatasetValue QgsMeshLayer::datasetValue( const QgsMeshDatasetIndex &index
       bool isOnFaces = dataProvider()->datasetGroupMetadata( index ).isOnFaces();
       if ( isOnFaces )
       {
-        int native_face_index = mTriangularMesh->trianglesToNativeFaces().at( face_index );
-        return dataProvider()->datasetValue( index, native_face_index );
+        int nativeFaceIndex = mTriangularMesh->trianglesToNativeFaces().at( face_index );
+        return dataProvider()->datasetValue( index, nativeFaceIndex );
       }
       else
       {

src/core/mesh/qgsmeshlayer.h

@@ -188,6 +188,8 @@ class CORE_EXPORT QgsMeshLayer : public QgsMapLayer
       *
       * Returns NaN for NaN values, for values outside range or when
       * triangular mesh is not yet initialized on given point
+      *
+      * \since QGIS 3.4
       */
     QgsMeshDatasetValue datasetValue( const QgsMeshDatasetIndex &index, const QgsPointXY &point ) const;
 

src/core/mesh/qgsmeshlayerinterpolator.h

@@ -59,11 +59,21 @@ class QgsMeshLayerInterpolator : public QgsRasterInterface
     int bandCount() const override;
     QgsRasterBlock *block( int, const QgsRectangle &extent, int width, int height, QgsRasterBlockFeedback *feedback = nullptr ) override;
 
-
-    static double interpolateFromVerticesData( const QgsPointXY &p1,
-        const QgsPointXY &p2,
-        const QgsPointXY &p3,
-        double val1, double val2, double val3, const QgsPointXY &pt );
+    /*
+    * Interpolates value based on known values on the vertices of a triangle
+    * \param p1 first vertex of the triangle
+    * \param p2 second vertex of the triangle
+    * \param p3 third vertex of the triangle
+    * \param val1 value on p1 of the triangle
+    * \param val2 value on p2 of the triangle
+    * \param val3 value on p3 of the triangle
+    * \param pt point where to calculate value
+    * \returns value on the point pt or NaN in case the point is outside the triangle
+    */
+    static double interpolateFromVerticesData(
+      const QgsPointXY &p1, const QgsPointXY &p2, const QgsPointXY &p3,
+      double val1, double val2, double val3, const QgsPointXY &pt
+    );
 
   private:
     const QgsTriangularMesh &mTriangularMesh;

src/core/mesh/qgstriangularmesh.cpp

@@ -15,9 +15,11 @@
  *                                                                         *
  ***************************************************************************/
 
+#include <memory>
 #include <QList>
 #include "qgsfeature.h"
-
+#include "qgspolygon.h"
+#include "qgslinestring.h"
 #include "qgstriangularmesh.h"
 #include "qgsrendercontext.h"
 #include "qgscoordinatetransform.h"
@@ -152,8 +154,7 @@ void QgsTriangularMesh::update( QgsMesh *nativeMesh, QgsRenderContext *context )
   {
     const QgsMeshFace &face = mTriangularMesh.faces.at( i ) ;
     QgsGeometry geom = QgsMeshUtils::toGeometry( face, mTriangularMesh.vertices );
-    bool success = mSpatialIndex.insertFeature( i, geom.boundingBox() );
-    Q_UNUSED( success );
+    ( void )mSpatialIndex.insertFeature( i, geom.boundingBox() );
   }
 }
 
@@ -182,26 +183,26 @@ int QgsTriangularMesh::faceIndexForPoint( const QgsPointXY &point ) const
   const QList<QgsFeatureId> face_indexes = mSpatialIndex.intersects( QgsRectangle( point, point ) );
   for ( QgsFeatureId fid : face_indexes )
   {
-    int face_index = static_cast<int>( fid );
-    const QgsMeshFace &face = mTriangularMesh.faces.at( face_index );
+    int faceIndex = static_cast<int>( fid );
+    const QgsMeshFace &face = mTriangularMesh.faces.at( faceIndex );
     const QgsGeometry geom = QgsMeshUtils::toGeometry( face, mTriangularMesh.vertices );
     if ( geom.contains( &point ) )
-      return face_index;
+      return faceIndex;
   }
   return -1;
 }
 
 QgsGeometry QgsMeshUtils::toGeometry( const QgsMeshFace &face, const QVector<QgsMeshVertex> &vertices )
 {
-  QVector<QgsPointXY> ring;
+  QVector<QgsPoint> ring;
   for ( int j = 0; j < face.size(); ++j )
   {
-    int vertex_id = face[j];
-    Q_ASSERT( vertex_id < vertices.size() );
-    const QgsPoint &vertex = vertices[vertex_id];
+    int vertexId = face[j];
+    Q_ASSERT( vertexId < vertices.size() );
+    const QgsPoint &vertex = vertices[vertexId];
     ring.append( vertex );
   }
-  QgsPolygonXY polygon;
-  polygon.append( ring );
-  return QgsGeometry::fromPolygonXY( polygon );
+  std::unique_ptr< QgsPolygon > polygon = qgis::make_unique< QgsPolygon >();
+  polygon->setExteriorRing( new QgsLineString( ring ) );
+  return QgsGeometry( std::move( polygon ) );
 }

src/core/mesh/qgstriangularmesh.h

@@ -83,6 +83,8 @@ class CORE_EXPORT QgsTriangularMesh
     /**
      * Returns triangle index that contains the given point, -1 if no such triangle exists
      * It uses spatial indexing
+     *
+     * \since QGIS 3.4
      */
     int faceIndexForPoint( const QgsPointXY &point ) const ;