//! Initialize data source with vector of nodes and vector of elements (triangles or quadrangles)

//! Face normals are calculated using the three first nodes of each element

//! Node normals are calculated averaging the normals of the neighboring elements

MeshDS_DataSource(double* Vertices, int nVerts1, int nVerts2, int* Faces, int nFaces1, int nFaces2);

MeshDS_DataSource(const Handle(Poly_Triangulation)& polyTri);

//! This method define the normal of the face for each element

//! This method define the normal of all nodes for each element

//! Returns geometry information about node ( if IsElement is False ) or element ( IsElement is True )

//! by co-ordinates. For element this method must return all its nodes co-ordinates in the strict order: X, Y, Z and

Handle(TColStd_HArray2OfReal) myNodeCoords;

Handle(TColStd_HArray2OfReal) myElemNormals;

Handle(TColStd_HArray2OfReal) myNodeNormals;

void InitializeFromData(double* Vertices, const int nVerts1, const int nVerts2, int* Faces, const int nFaces1, const int nFaces2);

};

class MeshDS_DataSource : public MeshVS_DataSource {

public:

MeshDS_DataSource(double* Vertices, int nVerts1, int nVerts2, int* Faces, int nFaces1, int nFaces2);

MeshDS_DataSource(const opencascade::handle<Poly_Triangulation> & polyTri);

Standard_Boolean GetGeom(Standard_Integer ID, Standard_Boolean IsElement, TColStd_Array1OfReal& Coords, Standard_Integer &OutValue, MeshVS_EntityType& Type);

Standard_Boolean GetGeomType(Standard_Integer ID, Standard_Boolean IsElement, MeshVS_EntityType& Type);

Standard_Address GetAddr(Standard_Integer ID, Standard_Boolean IsElement);