added static_assert in case of wrong ORDER parameter

dune/curvedsurfacegrid/geometry.hh

@@ -576,7 +576,7 @@ namespace Dune
 
     protected:
       VertexGeometry (Construct, const ReferenceElement& refElement, const LocalFunction& localFunction,
-                const LocalGeometry& lg)
+                      const LocalGeometry& lg)
         : Super(refElement, std::vector<GlobalCoordinate>{localFunction(lg.global(refElement.position(0,0)))})
       {}
 

dune/curvedsurfacegrid/gridfamily.hh

@@ -65,6 +65,7 @@ namespace Dune
         using LocalFunction = std::decay_t<decltype(localFunction(std::declval<GF const&>()))>;
 
         static const bool differentiableLocalFunction = DifferentiableLocalFunction<GF, LocalFunction>::value;
+        static_assert((differentiableLocalFunction || order>0), "Either provide a differentiable GridFunction or set ORDER > 0");
 
         using ctype = typename HostGrid::ctype;
 

example/example.cc

@@ -9,7 +9,6 @@
 #include <dune/common/exceptions.hh> // We use exceptions
 #include <dune/alugrid/grid.hh>
 #include <dune/curvedsurfacegrid/curvedsurfacegrid.hh>
-#include <dune/curvedsurfacegrid/gridfunctions/analyticgridfunction.hh>
 #include <dune/grid/io/file/gmshreader.hh>
 #include <dune/grid/io/file/vtk/vtkwriter.hh>
 #include <dune/grid/io/file/vtk/subsamplingvtkwriter.hh>
@@ -46,12 +45,10 @@ int main(int argc, char** argv)
   //case1: projection to actual sphere
   {
     SphereCoordFunction sphereCF(/*center=*/{0.0, 0.0, 0.0}, /*radius=*/1.0);
-    auto sphereGridFct = analyticGridFunction<HostGridType>(sphereCF);
-    using GridType = CurvedSurfaceGrid<decltype(sphereGridFct), ip_order>;
-    GridType grid(*hostGrid, sphereGridFct);
+    CurvedSurfaceGrid grid(*hostGrid, sphereCF, std::integral_constant<int, ip_order>{});
 
-    using GridView = GridType::LeafGridView;
-    GridView gridView = grid.leafGridView();
+    auto gridView = grid.leafGridView();
+    using GridView = decltype(gridView);
     VTKWriter<GridView> vtkWriter(gridView);
     vtkWriter.write("sphere1_real_elements");
     SubsamplingVTKWriter<GridView> ssvtkWriter(gridView, refinementIntervals(ip_order));
@@ -61,12 +58,10 @@ int main(int argc, char** argv)
   //case2: projection to a surface-mesh of a sphere
   {
     SurfaceDistanceCoordFunction<> surfdistCF("example/sphere_fine.vtu");
-    auto surfaceDistGridFct = analyticGridFunction<HostGridType>(surfdistCF);
-    using GridType = CurvedSurfaceGrid<decltype(surfaceDistGridFct), ip_order>;
-    GridType grid(*hostGrid, surfaceDistGridFct);
-
-    using GridView = GridType::LeafGridView;
-    GridView gridView = grid.leafGridView();
+    CurvedSurfaceGrid grid(*hostGrid, std::ref(surfdistCF), std::integral_constant<int, ip_order>{});
+    
+    auto gridView = grid.leafGridView();
+    using GridView = decltype(gridView);
     VTKWriter<GridView> vtkWriter(gridView);
     vtkWriter.write("sphere2_real_elements");
     SubsamplingVTKWriter<GridView> ssvtkWriter(gridView, refinementIntervals(ip_order));