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

  Program:   Visualization Toolkit
  Module:    vtkTransformToGrid.cxx
  Language:  C++
  Date:      $Date$
  Version:   $Revision$

  Copyright (c) 1993-2002 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.

=========================================================================*/
#include "vtkTransformToGrid.h"

#include "vtkAbstractTransform.h"
#include "vtkIdentityTransform.h"
#include "vtkImageData.h"
#include "vtkObjectFactory.h"

vtkCxxRevisionMacro(vtkTransformToGrid, "1.11");
vtkStandardNewMacro(vtkTransformToGrid);

vtkCxxSetObjectMacro(vtkTransformToGrid,Input,vtkAbstractTransform);

//----------------------------------------------------------------------------
vtkTransformToGrid::vtkTransformToGrid()
{
  this->Input = NULL;
  
  this->GridScalarType = VTK_FLOAT;

  for (int i = 0; i < 3; i++)
    {
    this->GridExtent[2*i] = this->GridExtent[2*i+1] = 0;
    this->GridOrigin[i] = 0.0f;
    this->GridSpacing[i] = 1.0f;
    }

  this->DisplacementScale = 1.0f;
  this->DisplacementShift = 0.0f;
}

//----------------------------------------------------------------------------
vtkTransformToGrid::~vtkTransformToGrid()
{
  this->SetInput(NULL);
}

//----------------------------------------------------------------------------
void vtkTransformToGrid::PrintSelf(ostream& os, vtkIndent indent)
{
  int i;

  this->Superclass::PrintSelf(os,indent);

  os << indent << "Input: (" << this->Input << ")\n"; 

  os << indent << "GridSpacing: (" << this->GridSpacing[0];
  for (i = 1; i < 3; ++i)
    {
    os << ", " << this->GridSpacing[i];
    }
  os << ")\n";
  
  os << indent << "GridOrigin: (" << this->GridOrigin[0];
  for (i = 1; i < 3; ++i)
    {
    os << ", " << this->GridOrigin[i];
    }
  os << ")\n";

  os << indent << "GridExtent: (" << this->GridExtent[0];
  for (i = 1; i < 6; ++i)
    {
    os << ", " << this->GridExtent[i];
    }
  os << ")\n";

  os << indent << "GridScalarType: " <<
    vtkImageScalarTypeNameMacro(this->GridScalarType) << "\n";

  this->UpdateShiftScale();

  os << indent << "DisplacementScale: " << this->DisplacementScale << "\n";
  os << indent << "DisplacementShift: " << this->DisplacementShift << "\n";
}

//----------------------------------------------------------------------------
// This method returns the largest data that can be generated.
void vtkTransformToGrid::ExecuteInformation()
{
  if (this->GetInput() == NULL)
    {
    vtkErrorMacro("Missing input");
    return;
    }

  this->Input->Update();

  this->GetOutput()->SetWholeExtent(this->GridExtent);
  this->GetOutput()->SetSpacing(this->GridSpacing);
  this->GetOutput()->SetOrigin(this->GridOrigin);
  this->GetOutput()->SetScalarType(this->GridScalarType);
  this->GetOutput()->SetNumberOfScalarComponents(3);
}

//----------------------------------------------------------------------------
// Return the maximum absolute displacement of the transform over
// the entire grid extent -- this is extremely robust and extremely
// inefficient, it should be possible to do much better than this.
void vtkTransformToGridMinMax(vtkTransformToGrid *self, int extent[6],
                              float &minDisplacement, float &maxDisplacement)
{
  vtkAbstractTransform *transform = self->GetInput();
  transform->Update();

  if (!transform)
    {
    minDisplacement = -1.0f;
    maxDisplacement = +1.0f;
    return;
    }

  float *spacing = self->GetGridSpacing();
  float *origin = self->GetGridOrigin();

  maxDisplacement = -1e37;
  minDisplacement = +1e37;

  float point[3],newPoint[3],displacement;

  for (int k = extent[4]; k <= extent[5]; k++)
    {
    point[2] = k*spacing[2] + origin[2];
    for (int j = extent[2]; j <= extent[3]; j++)
      {
      point[1] = j*spacing[1] + origin[1];
      for (int i = extent[0]; i <= extent[1]; i++)
        {
        point[0] = i*spacing[0] + origin[0];

        transform->InternalTransformPoint(point,newPoint);

        for (int l = 0; l < 3; l++)
          {
          displacement = newPoint[l] - point[l];

          if (displacement > maxDisplacement)
            {
            maxDisplacement = displacement;
            }

          if (displacement < minDisplacement)
            {
            minDisplacement = displacement;
            }
          }
        } 
      }
    }
} 

//----------------------------------------------------------------------------
void vtkTransformToGrid::UpdateShiftScale()
{
  int gridType = this->GridScalarType;

  // nothing to do for float or double
  if (gridType == VTK_FLOAT || gridType == VTK_DOUBLE)
    {
    this->DisplacementShift = 0.0f;
    this->DisplacementScale = 1.0f;
    vtkDebugMacro(<< "displacement (scale, shift) = (" << 
                  this->DisplacementScale << ", " << 
                  this->DisplacementShift << ")");  
    return;
    }

  // check mtime
  if (this->ShiftScaleTime.GetMTime() > this->GetMTime())
    {
    return;
    }

  // get the maximum displacement
  float minDisplacement, maxDisplacement;
  vtkTransformToGridMinMax(this,this->GridExtent,
                           minDisplacement,
                           maxDisplacement);

  vtkDebugMacro(<< "displacement (min, max) = (" << 
                minDisplacement << ", " << maxDisplacement << ")");

  float typeMin,typeMax;

  switch (gridType)
    {
    case VTK_SHORT:
      typeMin = VTK_SHORT_MIN;
      typeMax = VTK_SHORT_MAX;
      break;
    case VTK_UNSIGNED_SHORT:
      typeMin = VTK_UNSIGNED_SHORT_MIN;
      typeMax = VTK_UNSIGNED_SHORT_MAX;
      break;
    case VTK_CHAR:
      typeMin = VTK_CHAR_MIN;
      typeMax = VTK_CHAR_MAX;
      break;
    case VTK_UNSIGNED_CHAR:
      typeMin = VTK_UNSIGNED_CHAR_MIN;
      typeMax = VTK_UNSIGNED_CHAR_MAX;
      break;
    default:
      vtkErrorMacro(<< "UpdateShiftScale: Unknown input ScalarType");
      return;
    }
  
  this->DisplacementScale = ((maxDisplacement - minDisplacement)/
                             (typeMax - typeMin));
  this->DisplacementShift = ((typeMax*minDisplacement-typeMin*maxDisplacement)/
                             (typeMax - typeMin)); 

  if (this->DisplacementScale == 0.0f)
    {
    this->DisplacementScale = 1.0f;
    }

  vtkDebugMacro(<< "displacement (scale, shift) = (" << 
                this->DisplacementScale << ", " << 
                this->DisplacementShift << ")");  

  this->ShiftScaleTime.Modified();
}

//----------------------------------------------------------------------------
// macros to ensure proper round-to-nearest behaviour

inline void vtkGridRound(float val, unsigned char& rnd)
{
  rnd = (unsigned char)(val+0.5f);
}

inline void vtkGridRound(float val, char& rnd)
{
  rnd = (char)((val+128.5f)-128);
}

inline void vtkGridRound(float val, short& rnd)
{
  rnd = (short)((int)(val+32768.5f)-32768);
}

inline void vtkGridRound(float val, unsigned short& rnd)
{
  rnd = (unsigned short)(val+0.5f);
}

inline void vtkGridRound(float val, float& rnd)
{
  rnd = (float)(val);
}

//----------------------------------------------------------------------------
template<class T>
void vtkTransformToGridExecute(vtkTransformToGrid *self,
                               vtkImageData *grid, T *gridPtr, int extent[6], 
                               float shift, float scale, int id)
{
  vtkAbstractTransform *transform = self->GetInput();
  int isIdentity = 0;
  if (transform == 0)
    {
    transform = vtkIdentityTransform::New();
    isIdentity = 1;
    }

  float *spacing = grid->GetSpacing();
  float *origin = grid->GetOrigin();
  int *increments = grid->GetIncrements();

  float invScale = 1.0f/scale;

  float point[3];
  float newPoint[3];

  T *gridPtr0 = gridPtr;

  unsigned long count = 0;
  unsigned long target = (unsigned long)
    ((extent[5]-extent[4]+1)*(extent[3]-extent[2]+1)/50.0);
  target++;

  for (int k = extent[4]; k <= extent[5]; k++)
    {
    point[2] = k*spacing[2] + origin[2];
    T *gridPtr1 = gridPtr0;

    for (int j = extent[2]; j <= extent[3]; j++)
      {

      if (id == 0)
        {
        if (count % target == 0)
          {
          self->UpdateProgress(count/(50.0*target));
          }
        count++;
        }

      point[1] = j*spacing[1] + origin[1];
      gridPtr = gridPtr1;

      for (int i = extent[0]; i <= extent[1]; i++)
        {
        point[0] = i*spacing[0] + origin[0];

        transform->InternalTransformPoint(point,newPoint);
        
        vtkGridRound((newPoint[0] - point[0] - shift)*invScale,*gridPtr++);
        vtkGridRound((newPoint[1] - point[1] - shift)*invScale,*gridPtr++);
        vtkGridRound((newPoint[2] - point[2] - shift)*invScale,*gridPtr++);
        } 

      gridPtr1 += increments[1];
      }

    gridPtr0 += increments[2];
    }

  if (isIdentity)
    {
    transform->Delete();
    }
}       

//----------------------------------------------------------------------------
void vtkTransformToGrid::ExecuteData(vtkDataObject *output)
{
  vtkImageData *grid = this->AllocateOutputData(output);
  int *extent = grid->GetExtent();

  float *gridPtr = (float *)grid->GetScalarPointerForExtent(extent);
  int gridType = grid->GetScalarType();

  this->UpdateShiftScale();

  float scale = this->DisplacementScale;
  float shift = this->DisplacementShift;

  int id = 0;

  switch (gridType)
    {
    case VTK_FLOAT:
      vtkTransformToGridExecute(this, grid, (float *)(gridPtr), extent,
                                shift,scale,id);
      break;
    case VTK_SHORT:
      vtkTransformToGridExecute(this, grid, (short *)(gridPtr), extent,
                                shift,scale,id);
      break;
    case VTK_UNSIGNED_SHORT:
      vtkTransformToGridExecute(this, grid, (unsigned short *)(gridPtr),extent,
                                shift,scale,id);
      break;
    case VTK_CHAR:
      vtkTransformToGridExecute(this, grid, (char *)(gridPtr), extent,
                                shift,scale,id);
      break;
    case VTK_UNSIGNED_CHAR:
      vtkTransformToGridExecute(this, grid, (unsigned char *)(gridPtr), extent,
                                shift,scale,id);
      break;
    default:
      vtkErrorMacro(<< "Execute: Unknown input ScalarType");
    }
}

//----------------------------------------------------------------------------
unsigned long vtkTransformToGrid::GetMTime()
{
  unsigned long mtime = this->vtkImageSource::GetMTime();

  if (this->Input)
    {
    unsigned long mtime2 = this->Input->GetMTime();
    if (mtime2 > mtime)
      {
      mtime = mtime2;
      }
    }

  return mtime;
}
