diff --git a/AMDiS/src/VtkWriter.hh b/AMDiS/src/VtkWriter.hh
new file mode 100644
index 0000000000000000000000000000000000000000..f5557991778a95562650d736c1ab62ea84726e45
--- /dev/null
+++ b/AMDiS/src/VtkWriter.hh
@@ -0,0 +1,369 @@
+#include <list>
+#include <vector>
+#include "DOFVector.h"
+
+namespace AMDiS {
+
+ template<typename T>
+ void VtkWriter::writeFile(T &file)
+ {
+ int nVertices = (*dataCollector)[0]->getNumberVertices();
+ int nElements = (*dataCollector)[0]->getNumberElements();
+ int vertices = (*dataCollector)[0]->getMesh()->getGeo(VERTEX);
+
+ if ((dim == 2) && (degree == 2)) {
+ nVertices += (*dataCollector)[0]->getNumberInterpPoints();
+ nElements *= 4;
+ } else if ((dim == 2) && (degree == 3)) {
+ nVertices += (*dataCollector)[0]->getNumberInterpPoints();
+ nElements *= 9;
+ } else if ((dim == 2) && (degree == 4)) {
+ nVertices += (*dataCollector)[0]->getNumberInterpPoints();
+ nElements *= 16;
+ }
+
+ file << "<?xml version=\"1.0\"?>\n";
+ file << "<VTKFile type=\"UnstructuredGrid\" version=\"0.1\" byte_order=\"LittleEndian\">\n";
+ file << " <UnstructuredGrid>\n";
+ file << " <Piece NumberOfPoints=\"" << nVertices
+ << "\" NumberOfCells=\"" << nElements << "\">\n";
+ file << " <Points>\n";
+ file << " <DataArray type=\"Float32\" NumberOfComponents=\"3\" format=\"ascii\">\n";
+
+ writeVertexCoords(file);
+
+ file << " </DataArray>\n";
+ file << " </Points>\n";
+ file << " <Cells>\n";
+ file << " <DataArray type=\"Int32\" Name=\"offsets\">\n";
+
+ for (int i = 0; i < nElements; i++) {
+ file << " " << (i + 1) * vertices << "\n";
+ }
+
+ file << " </DataArray>\n";
+ file << " <DataArray type=\"UInt8\" Name=\"types\">\n";
+
+ for (int i = 0; i < nElements; i++) {
+ switch (vertices) {
+ case 2:
+ file << " 3\n";
+ break;
+ case 3:
+ file << " 5\n";
+ break;
+ case 4:
+ file << " 10\n";
+ break;
+ default:
+ break;
+ }
+ }
+
+ file << " </DataArray>\n";
+ file << " <DataArray type=\"Int32\" Name=\"connectivity\">\n";
+
+ writeConnectivity(file);
+
+ file << " </DataArray>\n";
+ file << " </Cells>\n";
+ file << " <PointData>\n";
+
+ for (int i = 0; i < static_cast<int>(dataCollector->size()); i++) {
+ file << " <DataArray type=\"Float32\" Name=\"value" << i
+ << "\" format=\"ascii\">\n";
+
+ writeVertexValues(file, i);
+
+ file << " </DataArray>\n";
+ }
+
+ file << " </PointData>\n";
+ file << " </Piece>\n";
+ file << " </UnstructuredGrid>\n";
+ file << "</VTKFile>\n";
+ }
+
+ template<typename T>
+ void writeVertexCoords(T &file)
+ {
+ DOFVector< std::list<VertexInfo> > *vertexInfos = (*dataCollector)[0]->getVertexInfos();
+ DOFVector< std::list<VertexInfo> >::Iterator it(vertexInfos, USED_DOFS);
+ int counter = 0;
+
+ // For all DOFs of vertices, write the coordinates.
+ for (it.reset(); !it.end(); ++it) {
+ // for all vertex infos of this DOF
+ std::list<VertexInfo>::iterator it2;
+ for (it2 = it->begin(); it2 != it->end(); ++it2) {
+ it2->outputIndex = counter++;
+ writeCoord(file, it2->coords);
+ }
+ }
+
+ // For the second dim case, write also the interpolation points.
+ if ((dim == 2) && (degree > 1)) {
+ DOFVector< std::list< WorldVector<double> > > *interpPointCoords = (*dataCollector)[0]->getInterpPointCoords();
+ DOFVector< std::list< WorldVector<double> > >::Iterator pointIt(interpPointCoords, USED_DOFS);
+
+ for (pointIt.reset(); !pointIt.end(); ++pointIt) {
+ std::list< WorldVector<double> >::iterator it2;
+ for (it2 = pointIt->begin(); it2 != pointIt->end(); ++it2) {
+ writeCoord(file, *it2);
+ }
+ }
+ }
+ }
+
+ template<typename T>
+ void writeVertexValues(T &file, int componentNo)
+ {
+ // DOFVector<int> *interpPointInd;
+ // DOFVector<double> *values;
+ // DOFVector< std::list<WorldVector<double> > > *dofCoords;
+
+ DOFVector<int> *interpPointInd = (*dataCollector)[componentNo]->getInterpPointInd();
+ DOFVector<double> *values = (*dataCollector)[componentNo]->getValues();
+ DOFVector< std::list<WorldVector<double> > > *dofCoords = (*dataCollector)[componentNo]->getDofCoords();
+
+ /*
+#ifdef _OPENMP
+#pragma omp critical
+#endif
+ {
+ interpPointInd = (*dataCollector)[componentNo]->getInterpPointInd();
+ values = (*dataCollector)[componentNo]->getValues();
+ dofCoords = (*dataCollector)[componentNo]->getDofCoords();
+ }
+ */
+ DOFVector<int>::Iterator intPointIt(interpPointInd, USED_DOFS);
+ DOFVector<double>::Iterator valueIt(values, USED_DOFS);
+ DOFVector< std::list<WorldVector<double> > >::Iterator coordIt(dofCoords, USED_DOFS);
+
+ // Write the values for all vertex DOFs.
+ for (intPointIt.reset(), valueIt.reset(), coordIt.reset();
+ !intPointIt.end();
+ ++intPointIt, ++valueIt, ++coordIt) {
+
+ if (*intPointIt == -2) {
+ for (int i = 0; i < static_cast<int>(coordIt->size()); i++) {
+ file << " " << (fabs(*valueIt) < 1e-40 ? 0.0 : *valueIt) << "\n";
+ }
+ }
+ }
+
+ // For the second dim case, write also the values of the interpolation points.
+ if ((dim == 2) && (degree > 1)) {
+ DOFVector< std::list<WorldVector<double> > >::Iterator
+ interpCoordIt((*dataCollector)[componentNo]->getInterpPointCoords(), USED_DOFS);
+
+ for (intPointIt.reset(), valueIt.reset(), interpCoordIt.reset();
+ !intPointIt.end();
+ ++intPointIt, ++valueIt, ++interpCoordIt) {
+
+ if (*intPointIt >= 0) {
+ for (int i = 0; i < static_cast<int>(interpCoordIt->size()); i++) {
+ file << " " << (fabs(*valueIt) < 1e-40 ? 0.0 : *valueIt) << "\n";
+ }
+ }
+ }
+ }
+ }
+
+ template<typename T>
+ void writeConnectivity(T &file)
+ {
+ // For the second dim case, and if higher order Lagrange elements are used,
+ // write the connectivity by extra functions.
+ if ((dim == 2) && (degree == 2)) {
+ writeConnectivity_dim2_degree2(file);
+ } else if ((dim == 2) && (degree == 3)) {
+ writeConnectivity_dim2_degree3(file);
+ } else if ((dim == 2) && (degree == 4)) {
+ writeConnectivity_dim2_degree4(file);
+ } else {
+ std::list<ElementInfo> *elements = (*dataCollector)[0]->getElementInfos();
+ std::list<ElementInfo>::iterator elementIt;
+ int vertices = (*dataCollector)[0]->getMesh()->getGeo(VERTEX);
+
+ for (elementIt = elements->begin(); elementIt != elements->end(); ++elementIt) {
+ // for all vertices
+ for (int i = 0; i < vertices; i++) {
+ file << " " << elementIt->vertexInfo[i]->outputIndex;
+ }
+ file << "\n";
+ }
+ }
+ }
+
+ template<typename T>
+ void writeConnectivity_dim2_degree2(T &file)
+ {
+ std::list<ElementInfo> *elements = (*dataCollector)[0]->getElementInfos();
+ std::list<ElementInfo>::iterator elementIt;
+
+ std::vector< std::vector<int> > *interpPoints = (*dataCollector)[0]->getInterpPoints();
+ std::vector< std::vector<int> >::iterator pointIt;
+
+ int nVertices = (*dataCollector)[0]->getNumberVertices();
+
+ for (pointIt = interpPoints->begin(), elementIt = elements->begin();
+ pointIt != interpPoints->end();
+ ++pointIt, ++elementIt) {
+
+ file << " " << elementIt->vertexInfo[0]->outputIndex
+ << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[2] + nVertices << "\n";
+
+ file << " " << elementIt->vertexInfo[2]->outputIndex
+ << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[1] + nVertices << "\n";
+
+ file << " " << elementIt->vertexInfo[1]->outputIndex
+ << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[2] + nVertices << "\n";
+
+ file << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[2] + nVertices << "\n";
+ }
+ }
+
+ template<typename T>
+ void writeConnectivity_dim2_degree3(T &file)
+ {
+ std::list<ElementInfo> *elements = (*dataCollector)[0]->getElementInfos();
+ std::list<ElementInfo>::iterator elementIt;
+
+ std::vector< std::vector<int> > *interpPoints = (*dataCollector)[0]->getInterpPoints();
+ std::vector< std::vector<int> >::iterator pointIt;
+
+ int nVertices = (*dataCollector)[0]->getNumberVertices();
+
+ for (pointIt = interpPoints->begin(), elementIt = elements->begin();
+ pointIt != interpPoints->end();
+ ++pointIt, ++elementIt) {
+
+ file << " " << elementIt->vertexInfo[0]->outputIndex
+ << " " << (*pointIt)[3] + nVertices
+ << " " << (*pointIt)[4] + nVertices << "\n";
+
+ file << " " << (*pointIt)[4] + nVertices
+ << " " << (*pointIt)[5] + nVertices
+ << " " << (*pointIt)[6] + nVertices << "\n";
+
+ file << " " << (*pointIt)[3] + nVertices
+ << " " << (*pointIt)[4] + nVertices
+ << " " << (*pointIt)[6] + nVertices << "\n";
+
+ file << " " << (*pointIt)[2] + nVertices
+ << " " << (*pointIt)[3] + nVertices
+ << " " << (*pointIt)[6] + nVertices << "\n";
+
+ file << " " << elementIt->vertexInfo[1]->outputIndex
+ << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[5] + nVertices << "\n";
+
+ file << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[6] + nVertices
+ << " " << (*pointIt)[5] + nVertices << "\n";
+
+ file << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[6] + nVertices << "\n";
+
+ file << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[2] + nVertices
+ << " " << (*pointIt)[6] + nVertices << "\n";
+
+ file << " " << elementIt->vertexInfo[2]->outputIndex
+ << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[2] + nVertices << "\n";
+
+
+ }
+ }
+
+ template<typename T>
+ void writeConnectivity_dim2_degree4(T &file)
+ {
+ std::list<ElementInfo> *elements = (*dataCollector)[0]->getElementInfos();
+ std::list<ElementInfo>::iterator elementIt;
+
+ std::vector< std::vector<int> > *interpPoints = (*dataCollector)[0]->getInterpPoints();
+ std::vector< std::vector<int> >::iterator pointIt;
+
+ int nVertices = (*dataCollector)[0]->getNumberVertices();
+
+ for (pointIt = interpPoints->begin(), elementIt = elements->begin();
+ pointIt != interpPoints->end();
+ ++pointIt, ++elementIt) {
+
+ file << " " << elementIt->vertexInfo[0]->outputIndex
+ << " " << (*pointIt)[5] + nVertices
+ << " " << (*pointIt)[6] + nVertices << "\n";
+
+ file << " " << (*pointIt)[5] + nVertices
+ << " " << (*pointIt)[9] + nVertices
+ << " " << (*pointIt)[6] + nVertices << "\n";
+
+ file << " " << (*pointIt)[6] + nVertices
+ << " " << (*pointIt)[7] + nVertices
+ << " " << (*pointIt)[9] + nVertices << "\n";
+
+ file << " " << (*pointIt)[7] + nVertices
+ << " " << (*pointIt)[9] + nVertices
+ << " " << (*pointIt)[10] + nVertices << "\n";
+
+ file << " " << (*pointIt)[7] + nVertices
+ << " " << (*pointIt)[8] + nVertices
+ << " " << (*pointIt)[10] + nVertices << "\n";
+
+ file << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[8] + nVertices
+ << " " << (*pointIt)[10] + nVertices << "\n";
+
+ file << " " << elementIt->vertexInfo[1]->outputIndex
+ << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[8] + nVertices << "\n";
+
+ file << " " << (*pointIt)[4] + nVertices
+ << " " << (*pointIt)[5] + nVertices
+ << " " << (*pointIt)[9] + nVertices << "\n";
+
+ file << " " << (*pointIt)[4] + nVertices
+ << " " << (*pointIt)[9] + nVertices
+ << " " << (*pointIt)[11] + nVertices << "\n";
+
+ file << " " << (*pointIt)[9] + nVertices
+ << " " << (*pointIt)[10] + nVertices
+ << " " << (*pointIt)[11] + nVertices << "\n";
+
+ file << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[10] + nVertices
+ << " " << (*pointIt)[11] + nVertices << "\n";
+
+ file << " " << (*pointIt)[0] + nVertices
+ << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[10] + nVertices << "\n";
+
+ file << " " << (*pointIt)[3] + nVertices
+ << " " << (*pointIt)[4] + nVertices
+ << " " << (*pointIt)[11] + nVertices << "\n";
+
+ file << " " << (*pointIt)[2] + nVertices
+ << " " << (*pointIt)[3] + nVertices
+ << " " << (*pointIt)[11] + nVertices << "\n";
+
+ file << " " << (*pointIt)[1] + nVertices
+ << " " << (*pointIt)[2] + nVertices
+ << " " << (*pointIt)[11] + nVertices << "\n";
+
+ file << " " << elementIt->vertexInfo[2]->outputIndex
+ << " " << (*pointIt)[2] + nVertices
+ << " " << (*pointIt)[3] + nVertices << "\n";
+
+ }
+ }
+
+}