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

  Program:   Visualization Toolkit
  Module:    vtkImageResample.cxx
  Language:  C++
  Date:      $Date$
  Version:   $Revision$
  Thanks:    Thanks to C. Charles Law who developed this class.

Copyright (c) 1993-2000 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 REGENTS 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.

=========================================================================*/
#include "vtkImageResample.h"
#include "vtkObjectFactory.h"



//------------------------------------------------------------------------------
vtkImageResample* vtkImageResample::New()
{
  // First try to create the object from the vtkObjectFactory
  vtkObject* ret = vtkObjectFactory::CreateInstance("vtkImageResample");
  if(ret)
    {
    return (vtkImageResample*)ret;
    }
  // If the factory was unable to create the object, then create it here.
  return new vtkImageResample;
}





// Macro for trilinear interpolation - do four linear interpolations on
// edges, two linear interpolations between pairs of edges, then a final
// interpolation between faces
#define vtkTrilinFuncMacro(v,x,y,z,a,b,c,d,e,f,g,h)         \
        t00 =   a + (x)*(b-a);      \
        t01 =   c + (x)*(d-c);      \
        t10 =   e + (x)*(f-e);      \
        t11 =   g + (x)*(h-g);      \
        t0  = t00 + (y)*(t01-t00);  \
        t1  = t10 + (y)*(t11-t10);  \
        v   = (T)( t0 + (z)*(t1-t0));

#define vtkBilinFuncMacro(v,x,y,a,b,c,d)         \
        t00 =   a + (x)*(b-a);      \
        t01 =   c + (x)*(d-c);      \
        v  = (T)(t00 + (y)*(t01-t00)); 

//----------------------------------------------------------------------------
// Constructor: Sets default filter to be identity.
vtkImageResample::vtkImageResample()
{
  this->MagnificationFactors[0] = 1.0;
  this->MagnificationFactors[1] = 1.0;
  this->MagnificationFactors[2] = 1.0;
  this->OutputSpacing[0] = 0.0; // not specified
  this->OutputSpacing[1] = 0.0; // not specified
  this->OutputSpacing[2] = 0.0; // not specified
  this->Interpolate = 1;
  this->Dimensionality = 3;
}

//----------------------------------------------------------------------------
void vtkImageResample::SetAxisOutputSpacing(int axis, float spacing)
{
  if (axis < 0 || axis > 2)
    {
    vtkErrorMacro("Bad axis: " << axis);
    return;
    }
  
  if (this->OutputSpacing[axis] != spacing)
    {
    this->OutputSpacing[axis] = spacing;
    this->Modified();
    if (spacing != 0.0)
      {
      // Delay computing the magnification factor.
      // Input might not be set yet.
      this->MagnificationFactors[axis] = 0.0; // Not computed yet.
      }
    }
}

//----------------------------------------------------------------------------
void vtkImageResample::SetAxisMagnificationFactor(int axis, float factor)
{
  if (axis < 0 || axis > 2)
    {
    vtkErrorMacro("Bad axis: " << axis);
    return;
    }
  
  if (this->MagnificationFactors[axis] == factor)
    {
    return;
    }
  this->Modified();
  this->MagnificationFactors[axis] = factor;
  // Spacing is no longer valid.
  this->OutputSpacing[axis] = 0.0; // Not computed yet.
}

//----------------------------------------------------------------------------
float vtkImageResample::GetAxisMagnificationFactor(int axis)
{
  if (axis < 0 || axis > 2)
    {
    vtkErrorMacro("Bad axis: " << axis);
    return 0.0;
    }
  
  if (this->MagnificationFactors[axis] == 0.0)
    {
    float *inputSpacing;
    if ( ! this->GetInput())
      {
      vtkErrorMacro("GetMagnificationFactor: Input not set.");
      return 0.0;
      }
    this->GetInput()->UpdateInformation();
    inputSpacing = this->GetInput()->GetSpacing();
    this->MagnificationFactors[axis] = 
      inputSpacing[axis] / this->OutputSpacing[axis];
    
    }

  vtkDebugMacro("Returning magnification factor " 
		<<  this->MagnificationFactors[axis] << " for axis "
		<< axis);
  
  return this->MagnificationFactors[axis];
}




//----------------------------------------------------------------------------
// This method computes the Region of input necessary to generate outRegion.
// It assumes offset and size are multiples of Magnify Factors.
void vtkImageResample::ComputeInputUpdateExtent(int inExt[6], 
						int outExt[6])
{
  int min, max, axis;
  float factor;

  memcpy(inExt, outExt, 6 * sizeof(int));

  for (axis = 0; axis < 3; axis++)
    {
    factor = this->GetAxisMagnificationFactor(axis);
    
    vtkDebugMacro("ComputeInputUpdateExtent (axis " << axis 
                  << ") factor " << factor);    
    
    min = outExt[axis*2];
    max = outExt[axis*2+1];
    
    min = (int)(floor((float)(min) / factor));
    max = (int)(ceil((float)(max) / factor));
    
    inExt[axis*2] = min;
    inExt[axis*2+1] = max;
    }
}


//----------------------------------------------------------------------------
// Computes any global image information associated with regions.
void vtkImageResample::ExecuteInformation(vtkImageData *inData, 
					  vtkImageData *outData) 
{
  int wholeMin, wholeMax, axis, ext[6];
  float spacing[3], factor;

  inData->GetWholeExtent(ext);
  inData->GetSpacing(spacing);
  
  for (axis = 0; axis < 3; axis++)
    {
    wholeMin = ext[axis*2];
    wholeMax = ext[axis*2+1];
    
    // Scale the output extent
    factor = this->GetAxisMagnificationFactor(axis);
    wholeMin = (int)(ceil((float)(wholeMin) * factor));
    wholeMax = (int)(floor((float)(wholeMax) * factor));
    
    // Change the data spacing
    spacing[axis] /= factor;
    
    ext[axis*2] = wholeMin;
    ext[axis*2+1] = wholeMax;
    
    // just in case  the input spacing has changed.
    if (this->OutputSpacing[axis] != 0.0)
      {
      // Cause MagnificationFactor to recompute.
      this->MagnificationFactors[axis] = 0.0;
      }
    }

  outData->SetWholeExtent(ext);
  outData->SetSpacing(spacing);
  
}


//----------------------------------------------------------------------------
template <class T>
static void vtkImageResampleExecuteNI(vtkImageResample *self,
                                      vtkImageData *inData, 
                                      T *inPtr, int vtkNotUsed(inExt)[6],
                                      vtkImageData *outData, T *outPtr,
                                      int outExt[6], int id)
{
  float magX = self->GetAxisMagnificationFactor(0);
  float magY = self->GetAxisMagnificationFactor(1);
  float magZ = self->GetAxisMagnificationFactor(2);

  float zPos, yPos, xPos;
  int idxC, idxX, idxY, idxZ;
  int inMaxX, inMaxY, inMaxZ;
  int maxC, maxX, maxY, maxZ;
  int inIncX, inIncY, inIncZ;
  int outIncX, outIncY, outIncZ;
  unsigned long count = 0;
  unsigned long target;
  T *inPtrZ, *inPtrY, *inPtrX, *outPtrC;
  
  // find the region to loop over
  maxC = outData->GetNumberOfScalarComponents();
  maxX = outExt[1] - outExt[0];
  maxY = outExt[3] - outExt[2]; 
  maxZ = outExt[5] - outExt[4]; 
  target = (unsigned long)(maxC*(maxZ+1)*(maxY+1)/50.0);
  target++;
  
  // Get increments to march through data 
  inData->GetIncrements(inIncX, inIncY, inIncZ);
  outData->GetContinuousIncrements(outExt, outIncX, outIncY, outIncZ);

  inData->GetExtent(idxC, inMaxX, idxC, inMaxY, idxC, inMaxZ);

  // find the starting sample locations
  float xStart = outExt[0]/magX;
  float yStart = outExt[2]/magY;
  float zStart = outExt[4]/magZ;
  xStart = xStart - ((int)xStart);
  yStart = yStart - ((int)yStart);
  zStart = zStart - ((int)zStart);

  float xFloatInc = 1.0/magX;
  float yFloatInc = 1.0/magY;  
  float zFloatInc = 1.0/magZ;
  
  // Loop through ouput pixels
  for (idxC = 0; idxC < maxC; idxC++)
    {
    outPtrC = outPtr + idxC;
    inPtrZ = inPtr + idxC;
    zPos = zStart;
    for (idxZ = 0; idxZ <= maxZ; idxZ++)
      {
      inPtrY = inPtrZ;
      yPos = yStart;
      for (idxY = 0; !self->AbortExecute && idxY <= maxY; idxY++)
        {
        if (!id) 
          {
          if (!(count%target))
            {
            self->UpdateProgress(count/(50.0*target));
            }
          count++;
          }
        
        inPtrX = inPtrY;
        xPos = xStart;
	for (idxX = 0; idxX <= maxX; idxX++)
	  {
          *outPtrC = (T)*inPtrX;
          outPtrC += maxC;
          xPos += xFloatInc;
          while (xPos > 0.5 ) 
            {
            inPtrX += inIncX;
            xPos -= 1.0;
            }
          }
        outPtrC += outIncY;
        yPos += yFloatInc;
        while (yPos > 0.5 ) 
          {
          inPtrY += inIncY;
          yPos -= 1.0;
          }
        }
      outPtrC += outIncZ;
      zPos += zFloatInc;
      while (zPos > 0.5) 
        {
        inPtrZ += inIncZ;
        zPos -= 1.0;
        }
      }
    }
}

//----------------------------------------------------------------------------
template <class T>
static void vtkImageResampleExecute2D(vtkImageResample *self,
                                      vtkImageData *inData, 
                                      T *inPtr, int inExt[6],
                                      vtkImageData *outData, T *outPtr,
                                      int outExt[6], int id)
{
  float magX = self->GetAxisMagnificationFactor(0);
  float magY = self->GetAxisMagnificationFactor(1);

  float t00, t01;
  float yPos, xPos;
  int idxC, idxX, idxY, idxZ;
  int inMaxX, inMaxY, inMaxZ;
  int maxC, maxX, maxY, maxZ;
  int inIncX, inIncY, inIncZ;
  int outIncX, outIncY, outIncZ;
  unsigned long count = 0;
  unsigned long target;
  int xMaxIdx, yMaxIdx;
  T *inPtrZ, *inPtrY, *inPtrX, *outPtrC;
  
  // find the region to loop over
  maxC = outData->GetNumberOfScalarComponents();
  maxX = outExt[1] - outExt[0];
  maxY = outExt[3] - outExt[2]; 
  maxZ = outExt[5] - outExt[4]; 
  target = (unsigned long)(maxC*(maxZ+1)*(maxY+1)/50.0);
  target++;
  
  // Get increments to march through data 
  inData->GetIncrements(inIncX, inIncY, inIncZ);
  outData->GetContinuousIncrements(outExt, outIncX, outIncY, outIncZ);

  inData->GetExtent(idxC, inMaxX, idxC, inMaxY, idxC, inMaxZ);

  // find the starting sample locations
  float xStart = outExt[0]/magX;
  float yStart = outExt[2]/magY;
  xStart = xStart - ((int)xStart);
  yStart = yStart - ((int)yStart);

  float xFloatInc = 1.0/magX;
  float yFloatInc = 1.0/magY;
  
  // compute the offsets to the other verts
  int off1 = inIncX;
  int off2 = inIncY;
  int off3 = inIncX + inIncY;
  float A,B,C,D;

  // we need to know what the last x will be without
  // going out of memory. We use a loop here so
  // that the same calculations are done. same
  // accumulated errors etc.
  xPos = xStart;
  xMaxIdx = maxX;
  int itmp = inExt[0];

  // we create these arrays to store some value we'll
  // use when incrementing along the x axis
  float *XRatios = new float [maxX+1];
  int *XSteps = new int [maxX+1];
  float *pXRatios = XRatios;
  int   *pXSteps = XSteps;
  
  for (idxX = 0; idxX <= maxX; idxX++)
    {
    xPos += xFloatInc;
    *pXSteps = 0;
    while (xPos >= 1.0 ) 
      {
      xPos -= 1.0;
      itmp++;
      *pXSteps = *pXSteps + 1;
      }
    if (itmp >= inMaxX && idxX <= xMaxIdx)
      {
      xMaxIdx = idxX - 1;
      }
    *pXRatios = xPos;
    pXRatios++;
    pXSteps++;
    }
  yPos = yStart;
  yMaxIdx = maxY;
  itmp = inExt[2];
  for (idxY = 0; idxY <= maxY; idxY++)
    {
    yPos += yFloatInc;
    while (yPos >= 1.0 ) 
      {
      yPos -= 1.0;
      itmp++;
      }
    if (itmp >= inMaxY && idxY <= yMaxIdx)
      {
      yMaxIdx = idxY - 1;
      }
    }
  
  // Loop through ouput pixels
  for (idxC = 0; idxC < maxC; idxC++)
    {
    outPtrC = outPtr + idxC;
    inPtrZ = inPtr + idxC;
    for (idxZ = 0; idxZ <= maxZ; idxZ++)
      {
      inPtrY = inPtrZ;
      yPos = yStart;
      off2 = inIncY;
      off3 = inIncX + inIncY;
      for (idxY = 0; !self->AbortExecute && idxY <= maxY; idxY++)
        {
        if (idxY > yMaxIdx)
          {
          off2 = 0;
          off3 = inIncX;
          }
        if (!id) 
          {
          if (!(count%target))
            {
            self->UpdateProgress(count/(50.0*target));
            }
          count++;
          }
        
        inPtrX = inPtrY;
        xPos = xStart;
        A = (float)*(inPtrX);
        B = (float)*(inPtrX + off1);
        C = (float)*(inPtrX + off2);
        D = (float)*(inPtrX + off3);
        pXRatios = XRatios;
        pXSteps = XSteps;
	for (idxX = 0; idxX <= xMaxIdx; idxX++)
	  {
          vtkBilinFuncMacro( *outPtrC, xPos, yPos, A, B, C, D);
          outPtrC += maxC;
          xPos = *pXRatios++;
          if (*pXSteps) 
            {
            inPtrX = inPtrX + *pXSteps*inIncX;
            A = (float)*(inPtrX);
            B = (float)*(inPtrX + off1);
            C = (float)*(inPtrX + off2);
            D = (float)*(inPtrX + off3);
            }
          pXSteps++;
          }
	for (;idxX <= maxX; idxX++)
	  {
          *outPtrC = (T)(B + (yPos)*(D-B));
          outPtrC += maxC;
          }
        outPtrC += outIncY;
        yPos += yFloatInc;
        while (yPos >= 1.0 ) 
          {
          inPtrY += inIncY;
          yPos -= 1.0;
          }
        }
      outPtrC += outIncZ;
      inPtrZ += inIncZ;
      }
    }
  delete [] XRatios;
  delete [] XSteps;
}


//----------------------------------------------------------------------------
template <class T>
static void vtkImageResampleExecute3D(vtkImageResample *self,
                                      vtkImageData *inData, T *inPtr, 
                                      int inExt[6],
                                      vtkImageData *outData, T *outPtr,
                                      int outExt[6], int id)
{
  float magZ = self->GetAxisMagnificationFactor(2);
  float magX = self->GetAxisMagnificationFactor(0);
  float magY = self->GetAxisMagnificationFactor(1);

  float t00, t01, t10, t11, t0, t1;
  float zPos, yPos, xPos;
  int idxC, idxX, idxY, idxZ;
  int inMaxX, inMaxY, inMaxZ;
  int maxC, maxX, maxY, maxZ;
  int inIncX, inIncY, inIncZ;
  int outIncX, outIncY, outIncZ;
  unsigned long count = 0;
  unsigned long target;
  int xMaxIdx, yMaxIdx, zMaxIdx;
  T *inPtrZ, *inPtrY, *inPtrX, *outPtrC;
  
  // find the region to loop over
  maxC = outData->GetNumberOfScalarComponents();
  maxX = outExt[1] - outExt[0];
  maxY = outExt[3] - outExt[2]; 
  maxZ = outExt[5] - outExt[4];

  target = (unsigned long)(maxC*(maxZ+1)*(maxY+1)/50.0);
  target++;
  
  // Get increments to march through data 
  inData->GetIncrements(inIncX, inIncY, inIncZ);
  outData->GetContinuousIncrements(outExt, outIncX, outIncY, outIncZ);

  inData->GetExtent(idxC, inMaxX, idxC, inMaxY, idxC, inMaxZ);

  // find the starting sample locations
  float xStart = outExt[0]/magX;
  float yStart = outExt[2]/magY;
  float zStart = outExt[4]/magZ;
  xStart = xStart - ((int)xStart);
  yStart = yStart - ((int)yStart);
  zStart = zStart - ((int)zStart);

  float xFloatInc = 1.0/magX;
  float yFloatInc = 1.0/magY;
  float zFloatInc = 1.0/magZ;

  // we create these arrays to store some value we'll
  // use when incrementing along the x axis
  float *XRatios = new float [maxX+1];
  int *XSteps = new int [maxX+1];
  float *pXRatios = XRatios;
  int   *pXSteps = XSteps;

  // we need to know what the last x will be without
  // going out of memory. We use a loop here so
  // that the same calculations are done. same
  // accumulated errors etc.
  xPos = xStart;
  xMaxIdx = maxX;
  int itmp = inExt[0];
  for (idxX = 0; idxX <= maxX; idxX++)
    {
    xPos += xFloatInc;
    *pXSteps = 0;
    while (xPos >= 1.0 ) 
      {
      xPos -= 1.0;
      itmp++;
      *pXSteps = *pXSteps + 1;
      }
    if (itmp >= inMaxX && idxX <= xMaxIdx)
      {
      xMaxIdx = idxX - 1;
      }
    *pXRatios = xPos;
    pXRatios++;
    pXSteps++;
    }

  yPos = yStart;
  yMaxIdx = maxY;
  itmp = inExt[2];
  for (idxY = 0; idxY <= maxY; idxY++)
    {
    yPos += yFloatInc;
    while (yPos >= 1.0 ) 
      {
      yPos -= 1.0;
      itmp++;
      }
    if (itmp >= inMaxY && idxY <= yMaxIdx)
      {
      yMaxIdx = idxY - 1;
      }
    }
  
  zPos = zStart;
  zMaxIdx = maxZ;
  itmp = inExt[4];
  for (idxZ = 0; idxZ <= maxZ; idxZ++)
    {
    zPos += zFloatInc;
    while (zPos >= 1.0 ) 
      {
      zPos -= 1.0;
      itmp++;
      }
    if (itmp >= inMaxZ && idxZ <= zMaxIdx)
      {
      zMaxIdx = idxZ - 1;
      }
    }
  
  // compute the offsets to the other verts
  int off1 = inIncX;
  int off2 = inIncY;
  int off3 = inIncX + inIncY;
  int off4 = inIncZ;
  int off5 = inIncZ + inIncX;
  int off6 = inIncZ + inIncY;
  int off7 = inIncZ + inIncY + inIncX;
  float A,B,C,D,E,F,G,H;
  
  // Loop through ouput pixels
  for (idxC = 0; idxC < maxC; idxC++)
    {
    zPos = zStart;
    inPtrZ = inPtr + idxC;
    outPtrC = outPtr + idxC;
    off4 = inIncZ;
    off5 = inIncZ + inIncX;
    off6 = inIncZ + inIncY;
    off7 = inIncZ + inIncY + inIncX;
    for (idxZ = 0; idxZ <= maxZ; idxZ++)
      {
      inPtrY = inPtrZ;
      yPos = yStart;
      off2 = inIncY;
      off3 = inIncY + inIncX;
      if (idxZ > zMaxIdx)
        {
        off4 = 0;
        off5 = inIncX;
        off6 = inIncY;
        off7 = inIncY + inIncX;
        }
      for (idxY = 0; !self->AbortExecute && idxY <= maxY; idxY++)
	{
        if (idxY > yMaxIdx)
          {
          off2 = 0;
          off3 = inIncX;
          if (idxZ > zMaxIdx)
            {
            off6 = 0;
            off7 = inIncX;
            }
          else
            {
            off6 = inIncZ;
            off7 = inIncZ + inIncX;
            }
          }
	if (!id) 
	  {
	  if (!(count%target))
	    {
	    self->UpdateProgress(count/(50.0*target));
	    }
	  count++;
	  }
	
	inPtrX = inPtrY;
        xPos = xStart;
        A = (float)*(inPtrX);
        B = (float)*(inPtrX + off1);
        C = (float)*(inPtrX + off2);
        D = (float)*(inPtrX + off3);
        E = (float)*(inPtrX + off4);
        F = (float)*(inPtrX + off5);
        G = (float)*(inPtrX + off6);
        H = (float)*(inPtrX + off7);
        pXRatios = XRatios;
        pXSteps = XSteps;
	for (idxX = 0; idxX <= xMaxIdx; idxX++)
	  {
          vtkTrilinFuncMacro( *outPtrC, xPos, yPos, zPos, 
                              A, B, C, D, E, F, G, H );
          outPtrC += maxC;
          xPos = *pXRatios++;
          if (*pXSteps) 
            {
            inPtrX = inPtrX + *pXSteps*inIncX;
            A = (float)*(inPtrX);
            B = (float)*(inPtrX + off1);
            C = (float)*(inPtrX + off2);
            D = (float)*(inPtrX + off3);
            E = (float)*(inPtrX + off4);
            F = (float)*(inPtrX + off5);
            G = (float)*(inPtrX + off6);
            H = (float)*(inPtrX + off7);
            }
          pXSteps++;
          }
	for (;idxX <= maxX; idxX++)
	  {
          vtkBilinFuncMacro( *outPtrC, yPos, zPos, B, D, F, H );
          outPtrC += maxC;
          }
        outPtrC += outIncY;
        yPos += yFloatInc;
        while (yPos >= 1.0 ) 
          {
          inPtrY += inIncY;
          yPos -= 1.0;
          }
	}
      outPtrC += outIncZ;
      zPos += zFloatInc;
      while (zPos >= 1.0) 
        {
        inPtrZ += inIncZ;
        zPos -= 1.0;
        }
      }
    }
  delete [] XRatios;
  delete [] XSteps;
}

template <class T>
static void vtkImageResampleExecute(vtkImageResample *self,
				  vtkImageData *inData, T *inPtr, int inExt[6],
				  vtkImageData *outData, T *outPtr,
				  int outExt[6], int id)
{
  float magZ = self->GetAxisMagnificationFactor(2);

  if (!self->GetInterpolate())
    {
    vtkImageResampleExecuteNI(self, inData, inPtr, inExt,
                              outData, outPtr, outExt, id);
    }
  else
    {
    if (magZ == 1.0 || self->GetDimensionality() < 3)
      {
      vtkImageResampleExecute2D(self, inData, inPtr, inExt,
                                outData, outPtr, outExt, id);
      return;
      }
    else
      {
      vtkImageResampleExecute3D(self, inData, inPtr, inExt,
                                outData, outPtr, outExt, id);
      return;
      }      
    }
  
}

void vtkImageResample::ThreadedExecute(vtkImageData *inData, 
				      vtkImageData *outData,
				      int outExt[6], int id)
{
  int inExt[6];
  this->ComputeInputUpdateExtent(inExt,outExt);
  void *inPtr = inData->GetScalarPointerForExtent(inExt);
  void *outPtr = outData->GetScalarPointerForExtent(outExt);
  
  vtkDebugMacro(<< "Execute: inData = " << inData 
  << ", outData = " << outData);
  
  // this filter expects that input is the same type as output.
  if (inData->GetScalarType() != outData->GetScalarType())
    {
    vtkErrorMacro(<< "Execute: input ScalarType, " << inData->GetScalarType()
    << ", must match out ScalarType " << outData->GetScalarType());
    return;
    }
  
  switch (inData->GetScalarType())
    {
    case VTK_DOUBLE:
      vtkImageResampleExecute(this, 
			     inData, (double *)(inPtr), inExt,
			     outData, (double *)(outPtr), outExt, id);
      break;
    case VTK_FLOAT:
      vtkImageResampleExecute(this, 
			     inData, (float *)(inPtr), inExt,
			     outData, (float *)(outPtr), outExt, id);
      break;
    case VTK_LONG:
      vtkImageResampleExecute(this, 
			     inData, (long *)(inPtr), inExt,
			     outData, (long *)(outPtr), outExt, id);
      break;
    case VTK_UNSIGNED_LONG:
      vtkImageResampleExecute(this, 
			     inData, (unsigned long *)(inPtr), inExt,
			     outData, (unsigned long *)(outPtr), outExt, id);
      break;
    case VTK_INT:
      vtkImageResampleExecute(this, 
			     inData, (int *)(inPtr), inExt,
			     outData, (int *)(outPtr), outExt, id);
      break;
    case VTK_UNSIGNED_INT:
      vtkImageResampleExecute(this, 
			     inData, (unsigned int *)(inPtr), inExt,
			     outData, (unsigned int *)(outPtr), outExt, id);
      break;
    case VTK_SHORT:
      vtkImageResampleExecute(this, 
			     inData, (short *)(inPtr), inExt,
			     outData, (short *)(outPtr), outExt, id);
      break;
    case VTK_UNSIGNED_SHORT:
      vtkImageResampleExecute(this, 
			     inData, (unsigned short *)(inPtr), inExt,
			     outData, (unsigned short *)(outPtr), outExt, id);
      break;
    case VTK_CHAR:
      vtkImageResampleExecute(this, 
			     inData, (char *)(inPtr), inExt,
			     outData, (char *)(outPtr), outExt, id);
      break;
    case VTK_UNSIGNED_CHAR:
      vtkImageResampleExecute(this, 
			     inData, (unsigned char *)(inPtr), inExt,
			     outData, (unsigned char *)(outPtr), outExt, id);
      break;
    default:
      vtkErrorMacro(<< "Execute: Unknown ScalarType");
      return;
    }
}

void vtkImageResample::PrintSelf(ostream& os, vtkIndent indent)
{
  vtkImageToImageFilter::PrintSelf(os,indent);
  os << indent << "Dimensionality: " << this->Dimensionality << "\n";
  os << indent << "Interpolate: " << (this->Interpolate ? "On\n" : "Off\n");
}

