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

  Program:   Visualization Toolkit
  Module:    vtkVolume16Reader.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// .NAME vtkVolume16Reader - read 16 bit image files
// .SECTION Description
// vtkVolume16Reader is a source object that reads 16 bit image files.
//
// Volume16Reader creates structured point datasets. The dimension of the 
// dataset depends upon the number of files read. Reading a single file 
// results in a 2D image, while reading more than one file results in a 
// 3D volume.
//
// File names are created using FilePattern and FilePrefix as follows:
// sprintf (filename, FilePattern, FilePrefix, number);
// where number is in the range ImageRange[0] to ImageRange[1]. If
// ImageRange[1] <= ImageRange[0], then slice number ImageRange[0] is
// read. Thus to read an image set ImageRange[0] = ImageRange[1] = slice 
// number. The default behavior is to read a single file (i.e., image slice 1).
//
// The DataMask instance variable is used to read data files with imbedded
// connectivity or segmentation information. For example, some data has
// the high order bit set to indicate connected surface. The DataMask allows
// you to select this data. Other important ivars include HeaderSize, which
// allows you to skip over initial info, and SwapBytes, which turns on/off
// byte swapping.
//
// The Transform instance variable specifies a permutation transformation
// to map slice space into world space. vtkImageReader has replaced the
// functionality of this class and should be used instead.

// .SECTION See Also
// vtkSliceCubes vtkMarchingCubes vtkImageReader

#ifndef __vtkVolume16Reader_h
#define __vtkVolume16Reader_h

#include "vtkVolumeReader.h"

class vtkTransform;
class vtkUnsignedCharArray;
class vtkUnsignedShortArray;

#define VTK_FILE_BYTE_ORDER_BIG_ENDIAN 0
#define VTK_FILE_BYTE_ORDER_LITTLE_ENDIAN 1

class VTK_IO_EXPORT vtkVolume16Reader : public vtkVolumeReader
{
public:
  vtkTypeMacro(vtkVolume16Reader,vtkVolumeReader);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Construct object with NULL file prefix; file pattern "%s.%d"; image range 
  // set to (1,1); data origin (0,0,0); data spacing (1,1,1); no data mask;
  // header size 0; and byte swapping turned off.
  static vtkVolume16Reader *New();

  // Description:
  // Specify the dimensions for the data.
  vtkSetVector2Macro(DataDimensions,int);
  vtkGetVectorMacro(DataDimensions,int,2);

  // Description:
  // Specify a mask used to eliminate data in the data file (e.g.,
  // connectivity bits).
  vtkSetMacro(DataMask,unsigned short);
  vtkGetMacro(DataMask,unsigned short);

  // Description:
  // Specify the number of bytes to seek over at start of image.
  vtkSetMacro(HeaderSize,int);
  vtkGetMacro(HeaderSize,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 transformation matrix to transform the data from slice space
  // into world space. This matrix must be a permutation matrix. To qualify,
  // the sums of the rows must be + or - 1.
  virtual void SetTransform(vtkTransform*);
  vtkGetObjectMacro(Transform,vtkTransform);

  // Description:
  // Other objects make use of these methods
  vtkImageData *GetImage(int ImageNumber);

protected:
  vtkVolume16Reader();
  ~vtkVolume16Reader();

  virtual int RequestData(vtkInformation *, vtkInformationVector **, vtkInformationVector *);
  virtual int RequestInformation(vtkInformation *, vtkInformationVector **, vtkInformationVector *);
  int   DataDimensions[2];
  unsigned short DataMask;
  int   SwapBytes;
  int   HeaderSize;
  vtkTransform *Transform;

  void TransformSlice (unsigned short *slice, unsigned short *pixels, int k, int dimensions[3], int bounds[3]);
  void ComputeTransformedDimensions(int dimensions[3]);
  void ComputeTransformedBounds(int bounds[6]);
  void ComputeTransformedSpacing(double Spacing[3]);
  void ComputeTransformedOrigin(double origin[3]);
  void AdjustSpacingAndOrigin(int dimensions[3], double Spacing[3], double origin[3]);
  void ReadImage(int ImageNumber, vtkUnsignedShortArray *);
  void ReadVolume(int FirstImage, int LastImage, vtkUnsignedShortArray *);
  int Read16BitImage(FILE *fp, unsigned short *pixels, int xsize, int ysize, 
                     int skip, int swapBytes);

private:
  vtkVolume16Reader(const vtkVolume16Reader&);  // Not implemented.
  void operator=(const vtkVolume16Reader&);  // Not implemented.
};

#endif