Handle polyhedra in vtkUnstructuredGridWriter.

Change-Id: I6c20eb8650e2b079c8b1f581c9727a3d8205087a

IO/Legacy/vtkUnstructuredGridWriter.cxx

@@ -16,10 +16,17 @@
 
 #include "vtkByteSwap.h"
 #include "vtkCellArray.h"
+#include "vtkCellIterator.h"
+#include "vtkErrorCode.h"
 #include "vtkInformation.h"
 #include "vtkObjectFactory.h"
+#include "vtkSmartPointer.h"
 #include "vtkUnstructuredGrid.h"
 
+#include <algorithm>
+#include <iterator>
+#include <vector>
+
 #if !defined(_WIN32) || defined(__CYGWIN__)
 # include <unistd.h> /* unlink */
 #else
@@ -69,12 +76,29 @@ void vtkUnstructuredGridWriter::WriteData()
     unlink(this->FileName);
     return;
     }
-  if (!this->WriteCells(fp, input->GetCells(),"CELLS"))
+
+  // Write cells. Check for faces so that we can handle them if present:
+  if (input->GetFaces() != NULL)
     {
-    vtkErrorMacro("Ran out of disk space; deleting file: " << this->FileName);
-    this->CloseVTKFile(fp);
-    unlink(this->FileName);
-    return;
+    // Handle face data:
+    if (!this->WriteCellsAndFaces(fp, input, "CELLS"))
+      {
+      vtkErrorMacro("Ran out of disk space; deleting file: " << this->FileName);
+      this->CloseVTKFile(fp);
+      unlink(this->FileName);
+      return;
+      }
+    }
+  else
+    {
+    // Fall back to superclass:
+    if (!this->WriteCells(fp, input->GetCells(),"CELLS"))
+      {
+      vtkErrorMacro("Ran out of disk space; deleting file: " << this->FileName);
+      this->CloseVTKFile(fp);
+      unlink(this->FileName);
+      return;
+      }
     }
 
   //
@@ -124,6 +148,81 @@ void vtkUnstructuredGridWriter::WriteData()
   this->CloseVTKFile(fp);
 }
 
+int vtkUnstructuredGridWriter::WriteCellsAndFaces(
+    ostream *fp, vtkUnstructuredGrid *grid, const char *label)
+{
+  if (!grid->GetCells())
+    {
+    return 1;
+    }
+
+  // Create a copy of the cell data with the face streams expanded.
+  // Do this before writing anything so that we know the size.
+  // Use ints to represent vtkIdTypes, since that's what the superclass does.
+  std::vector<int> cells;
+  cells.reserve(grid->GetNumberOfCells() * grid->GetMaxCellSize());
+
+  vtkSmartPointer<vtkCellIterator> it =
+      vtkSmartPointer<vtkCellIterator>::Take(grid->NewCellIterator());
+
+  for (it->InitTraversal(); !it->IsDoneWithTraversal(); it->GoToNextCell())
+    {
+    if (it->GetCellType() != VTK_POLYHEDRON)
+      {
+      vtkIdType cellSize = it->GetNumberOfPoints();
+      cells.push_back(static_cast<int>(cellSize));
+      std::copy(it->GetPointIds()->GetPointer(0),
+                it->GetPointIds()->GetPointer(cellSize),
+                std::back_inserter(cells));
+      }
+    else
+      {
+      vtkIdType cellSize = it->GetFaces()->GetNumberOfIds();
+      cells.push_back(static_cast<int>(cellSize));
+      std::copy(it->GetFaces()->GetPointer(0),
+                it->GetFaces()->GetPointer(cellSize),
+                std::back_inserter(cells));
+      }
+    }
+
+  if (cells.empty())
+    { // Nothing to do.
+    return 1;
+    }
+
+  *fp << label << " " << grid->GetNumberOfCells() << " "
+      << cells.size() << "\n";
+
+  if ( this->FileType == VTK_ASCII )
+    { // Write each cell out to a separate line, must traverse:
+    std::vector<int>::const_iterator cellStart = cells.begin();
+    std::vector<int>::const_iterator cellEnd;
+    vtkIdType nCells = grid->GetNumberOfCells();
+    while (nCells-- > 0)
+      {
+      cellEnd = cellStart + (*cellStart + 1);
+      while (cellStart != cellEnd)
+        *fp << static_cast<int>(*cellStart++) << " ";
+      *fp << "\n";
+      }
+    }
+  else
+    {
+    // Just dump the cell data
+    vtkByteSwap::SwapWrite4BERange(&cells[0], cells.size(), fp);
+    *fp << "\n";
+    }
+
+  fp->flush();
+  if (fp->fail())
+    {
+    this->SetErrorCode(vtkErrorCode::OutOfDiskSpaceError);
+    return 0;
+    }
+
+  return 1;
+}
+
 int vtkUnstructuredGridWriter::FillInputPortInformation(int,
                                                         vtkInformation *info)
 {

IO/Legacy/vtkUnstructuredGridWriter.h

@@ -44,6 +44,9 @@ protected:
 
   void WriteData();
 
+  int WriteCellsAndFaces(ostream *fp, vtkUnstructuredGrid *grid,
+                         const char *label);
+
   virtual int FillInputPortInformation(int port, vtkInformation *info);
 
 private: