InputSwan.cpp

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////////////////////////////////////////////////////////////////////////////////
//
//  File: InputSwan.cpp
//
//  For more information, please see: http://www.nektar.info/
//
//  The MIT License
//
//  Copyright (c) 2006 Division of Applied Mathematics, Brown University (USA),
//  Department of Aeronautics, Imperial College London (UK), and Scientific
//  Computing and Imaging Institute, University of Utah (USA).
//
//  License for the specific language governing rights and limitations under
//  Permission is hereby granted, free of charge, to any person obtaining a
//  copy of this software and associated documentation files (the "Software"),
//  to deal in the Software without restriction, including without limitation
//  the rights to use, copy, modify, merge, publish, distribute, sublicense,
//  and/or sell copies of the Software, and to permit persons to whom the
//  Software is furnished to do so, subject to the following conditions:
//
//  The above copyright notice and this permission notice shall be included
//  in all copies or substantial portions of the Software.
//
//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
//  OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
//  THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
//  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
//  DEALINGS IN THE SOFTWARE.
//
//  Description: Swansea session converter.
//
////////////////////////////////////////////////////////////////////////////////

#include <iostream>
using namespace std;

#include "MeshElements.h"
#include "InputSwan.h"

namespace Nektar
{
    namespace Utilities
    {
        ModuleKey InputSwan::className = 
            GetModuleFactory().RegisterCreatorFunction(
                ModuleKey(eInputModule, "plt"), InputSwan::create,
                "Reads Swansea plt format for third-order tetrahedra.");
        
        InputSwan::InputSwan(MeshSharedPtr m) : InputModule(m)
        {
            
        }

        InputSwan::~InputSwan()
        {
            
        }

        void InputSwan::Process()
        {
            // Open the file stream.
            OpenStream();

            vector<vector<NodeSharedPtr> > elementList;
            vector<int> tmp, tets;
            vector<double> pts;

            if (m_mesh->m_verbose)
            {
                cout << "InputSwan: Start reading file..." << endl;
            }

            m_mesh->m_expDim = 3;
            m_mesh->m_spaceDim = 3;
            
            // First read in header; 4 integers containing number of tets,
            // number of points, nas2 (unknown) and order of the grid
            // (i.e. GridOrder = 3 => cubic mesh).
            tmp.resize(6);
            m_mshFile.read(reinterpret_cast<char*>(&tmp[0]),
                         static_cast<int>       (6*sizeof(int))); 
            
            if (tmp[0] != tmp[5] || tmp[0] != 4*sizeof(int))
            {
                cout << "Header data broken" << endl;
                m_mshFile.close();
                return;
            }
            
            int NB_Tet    = tmp[1];
            int NB_Points = tmp[2];
            int GridOrder = tmp[4];
            int ND        = (GridOrder+1)*(GridOrder+2)*(GridOrder+3)/6;

            cout << "NB_Tet    = " << NB_Tet << endl;
            cout << "NB_Points = " << NB_Points << endl;
            cout << "GridOrder = " << GridOrder << endl;
            cout << "ND        = " << ND << endl;
            
            // Now read in list of tetrahedra. Each tet has ND points, and
            // data are ordered with memory traversed fastest with point
            // number.
            tets.resize(ND*NB_Tet+2);
            m_mshFile.read(reinterpret_cast<char*>(&tets[0]),
                         static_cast<int>       ((ND*NB_Tet+2)*sizeof(int)));

            if (tets[0] != tets[ND*NB_Tet+1] || tets[0] != ND*NB_Tet*sizeof(int))
            {
                cout << "ERROR [InputSwan]: Tetrahedron data broken." << endl;
                m_mshFile.close();
                return;
            }

            // Finally, read point data: NB_Points tuples (x,y,z).
            tmp.resize(2);
            pts.resize(3*NB_Points);
            m_mshFile.read(reinterpret_cast<char*>(&tmp[0]),
                         static_cast<int>       (sizeof(int)));
            m_mshFile.read(reinterpret_cast<char*>(&pts[0]),
                         static_cast<int>       (3*NB_Points*sizeof(double)));
            m_mshFile.read(reinterpret_cast<char*>(&tmp[1]),
                         static_cast<int>       (sizeof(int)));

            if (tmp[0] != tmp[1] || tmp[0] != 3*NB_Points*sizeof(double))
            {
                cout << "ERROR [InputSwan]: Point data broken." << endl;
                m_mshFile.close();
                return;
            }

            int vid = 0, i, j;
            LibUtilities::ShapeType elType = LibUtilities::eTetrahedron;

            // Read in list of vertices.
            for (i = 0; i < NB_Points; ++i)
            {
                double x    = pts [            i];
                double y    = pts [1*NB_Points+i];
                double z    = pts [2*NB_Points+i];
                m_mesh->m_node.push_back(boost::shared_ptr<Node>(new Node(vid, x, y, z)));
                vid++;
            }
            
            // Iterate over list of tetrahedra: for each, create nodes. At the
            // moment discard high order data and create linear mesh.
            for (i = 0; i < NB_Tet; ++i)
            {
                vector<NodeSharedPtr> nodeList;
                for (j = 0; j < 20; ++j)
                {
                    int vid = tets[j*NB_Tet+i+1];
                    nodeList.push_back(m_mesh->m_node[vid-1]);
                }
                
                vector<int> tags;
                tags.push_back(0);      // composite
                tags.push_back(elType); // element type

                ElmtConfig conf(elType,3,true,true);
                ElementSharedPtr E = GetElementFactory().
                    CreateInstance(elType,conf,nodeList,tags);
                m_mesh->m_element[3].push_back(E);
            }
            
            // Attempt to read in composites. Need to determine number of
            // triangles from data.
            tmp.resize(2);
            m_mshFile.read(reinterpret_cast<char*>(&tmp[0]),
                         static_cast<int>       (sizeof(int)));
            int n_tri = tmp[0]/sizeof(int)/5;
            tets.resize(n_tri*5);
            m_mshFile.read(reinterpret_cast<char*>(&tets[0]),
                         static_cast<int>       (tmp[0]));
            m_mshFile.read(reinterpret_cast<char*>(&tmp[1]),
                         static_cast<int>       (sizeof(int)));
            
            if (tmp[0] != tmp[1])
            {
                cout << "ERROR [InputSwan]: Surface data broken." << endl;
                m_mshFile.close();
                return;
            }

            elType = LibUtilities::eTriangle;
            
            // Process list of triangles forming surfaces.
            for (i = 0; i < n_tri; ++i)
            {
                vector<NodeSharedPtr> nodeList;
                
                for (j = 0; j < 3; ++j)
                {
                    nodeList.push_back(m_mesh->m_node[tets[i+j*n_tri]-1]);
                }
                
                vector<int> tags;
                tags.push_back(1);      // composite
                tags.push_back(elType); // element type
                
                ElmtConfig conf(elType,1,false,false);
                ElementSharedPtr E = GetElementFactory().
                    CreateInstance(elType,conf,nodeList,tags);
                m_mesh->m_element[2].push_back(E);
            }

            m_mshFile.close();

            // Process the rest of the mesh.
            ProcessVertices  ();
            ProcessEdges     ();
            ProcessFaces     ();
            ProcessElements  ();
            ProcessComposites();
        }
    }
}