/*=========================================================================

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkMCubesReader.h,v $
  Language:  C++
  Date:      $Date: 2001/10/11 13:37:31 $
  Version:   $Revision: 1.49 $


Copyright (c) 1993-2001 Ken Martin, Will Schroeder, Bill Lorensen 
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

 * Redistributions of source code must retain the above copyright notice,
   this list of conditions and the following disclaimer.

 * Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation
   and/or other materials provided with the distribution.

 * Neither name of Ken Martin, Will Schroeder, or Bill Lorensen nor the names
   of any contributors may be used to endorse or promote products derived
   from this software without specific prior written permission.

 * Modified source versions must be plainly marked as such, and must not be
   misrepresented as being the original software.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR
ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

=========================================================================*/
// .NAME vtkMCubesReader - read binary marching cubes file
// .SECTION Description
// vtkMCubesReader is a source object that reads binary marching cubes
// files. (Marching cubes is an isosurfacing technique that generates 
// many triangles.) The binary format is supported by W. Lorensen's
// marching cubes program (and the vtkSliceCubes object). The format 
// repeats point coordinates, so this object will merge the points 
// with a vtkLocator object. You can choose to supply the vtkLocator 
// or use the default.

// .SECTION Caveats
// Binary files assumed written in sun/hp/sgi (i.e., Big Endian) form.
//
// Because points are merged when read, degenerate triangles may be removed.
// Thus the number of triangles read may be fewer than the number of triangles
// actually created.
//
// The point merging does not take into account that the same point may have
// different normals. For example, running vtkPolyDataNormals after
// vtkContourFilter may split triangles because of the FeatureAngle
// ivar. Subsequent reading with vtkMCubesReader will merge the points and
// use the first point's normal. For the most part, this is undesirable.
//
// Normals are generated from the gradient of the data scalar values. Hence
// the normals may on occasion point in a direction inconsistent with the
// ordering of the triangle vertices. If this happens, the resulting surface
// may be "black".  Reverse the sense of the FlipNormals boolean flag to
// correct this.

// .SECTION See Also
// vtkContourFilter vtkMarchingCubes vtkSliceCubes vtkLocator

#ifndef __vtkMCubesReader_h
#define __vtkMCubesReader_h

#include <stdio.h>
#include "vtkPolyDataSource.h"
#include "vtkPoints.h"
#include "vtkCellArray.h"

#define VTK_FILE_BYTE_ORDER_BIG_ENDIAN 0
#define VTK_FILE_BYTE_ORDER_LITTLE_ENDIAN 1

class VTK_IO_EXPORT vtkMCubesReader : public vtkPolyDataSource 
{
public:
  vtkTypeMacro(vtkMCubesReader,vtkPolyDataSource);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Construct object with FlipNormals turned off and Normals set to true.
  static vtkMCubesReader *New();

  // Description:
  // Specify file name of marching cubes file.
  vtkSetStringMacro(FileName);
  vtkGetStringMacro(FileName);

  // Description:
  // Set / get the file name of the marching cubes limits file.
  vtkSetStringMacro(LimitsFileName);
  vtkGetStringMacro(LimitsFileName);

  // Description:
  // Specify a header size if one exists. The header is skipped and not used at this time.
  vtkSetClampMacro(HeaderSize,int,0,VTK_LARGE_INTEGER);
  vtkGetMacro(HeaderSize,int);

  // Description:
  // Specify whether to flip normals in opposite direction. Flipping ONLY
  // changes the direction of the normal vector. Contrast this with flipping
  // in vtkPolyDataNormals which flips both the normal and the cell point
  // order.
  vtkSetMacro(FlipNormals,int);
  vtkGetMacro(FlipNormals,int);
  vtkBooleanMacro(FlipNormals,int);

  // Description:
  // Specify whether to read normals.
  vtkSetMacro(Normals,int);
  vtkGetMacro(Normals,int);
  vtkBooleanMacro(Normals,int);

  // Description:
  // These methods should be used instead of the SwapBytes methods.
  // They indicate the byte ordering of the file you are trying
  // to read in. These methods will then either swap or not swap
  // the bytes depending on the byte ordering of the machine it is
  // being run on. For example, reading in a BigEndian file on a
  // BigEndian machine will result in no swapping. Trying to read
  // the same file on a LittleEndian machine will result in swapping.
  // As a quick note most UNIX machines are BigEndian while PC's
  // and VAX tend to be LittleEndian. So if the file you are reading
  // in was generated on a VAX or PC, SetDataByteOrderToLittleEndian otherwise
  // SetDataByteOrderToBigEndian. 
  void SetDataByteOrderToBigEndian();
  void SetDataByteOrderToLittleEndian();
  int GetDataByteOrder();
  void SetDataByteOrder(int);
  const char *GetDataByteOrderAsString();

  // Description:
  // Turn on/off byte swapping.
  vtkSetMacro(SwapBytes,int);
  vtkGetMacro(SwapBytes,int);
  vtkBooleanMacro(SwapBytes,int);

  // Description:
  // Set / get a spatial locator for merging points. By default, 
  // an instance of vtkMergePoints is used.
  void SetLocator(vtkPointLocator *locator);
  vtkGetObjectMacro(Locator,vtkPointLocator);

  // Description:
  // Create default locator. Used to create one when none is specified.
  void CreateDefaultLocator();
  
  // Description:
  // Return the mtime also considering the locator.
  unsigned long GetMTime();

protected:
  vtkMCubesReader();
  ~vtkMCubesReader();

  void Execute();

  char *FileName;
  char *LimitsFileName;
  vtkPointLocator *Locator;
  int SwapBytes;
  int HeaderSize;
  int FlipNormals;
  int Normals;

private:
  vtkMCubesReader(const vtkMCubesReader&);  // Not implemented.
  void operator=(const vtkMCubesReader&);  // Not implemented.
};

#endif