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

  Program:   Visualization Toolkit
  Module:    vtkGPUVolumeRayCastMapper.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 vtkGPUVolumeRayCastMapper - Ray casting performed on the GPU.
// .SECTION Description
// vtkGPUVolumeRayCastMapper is a volume mapper that performs ray casting on
// the GPU using fragment programs.
//


#ifndef vtkGPUVolumeRayCastMapper_h
#define vtkGPUVolumeRayCastMapper_h

#include "vtkRenderingVolumeModule.h" // For export macro
#include "vtkVolumeMapper.h"

class vtkVolumeProperty;
class vtkRenderWindow;

//class vtkKWAMRVolumeMapper; // friend class.

class VTKRENDERINGVOLUME_EXPORT vtkGPUVolumeRayCastMapper : public vtkVolumeMapper
{
public:
  static vtkGPUVolumeRayCastMapper *New();
  vtkTypeMacro(vtkGPUVolumeRayCastMapper,vtkVolumeMapper);
  void PrintSelf( ostream& os, vtkIndent indent );

  // Description:
  // If AutoAdjustSampleDistances is on, the the ImageSampleDistance
  // will be varied to achieve the allocated render time of this
  // prop (controlled by the desired update rate and any culling in
  // use).
  vtkSetClampMacro( AutoAdjustSampleDistances, int, 0, 1 );
  vtkGetMacro( AutoAdjustSampleDistances, int );
  vtkBooleanMacro( AutoAdjustSampleDistances, int );

  // Description:
  // If UseJittering is on, each ray traversal direction will be
  // perturbed slightly using a noise-texture to get rid of wood-grain
  // effect.
  vtkSetClampMacro( UseJittering, int, 0, 1 );
  vtkGetMacro( UseJittering, int );
  vtkBooleanMacro( UseJittering, int );

  // Description:
  // Set/Get the distance between samples used for rendering
  // when AutoAdjustSampleDistances is off, or when this mapper
  // has more than 1 second allocated to it for rendering.
  // Initial value is 1.0.
  vtkSetMacro( SampleDistance, float );
  vtkGetMacro( SampleDistance, float );

  // Description:
  // Sampling distance in the XY image dimensions. Default value of 1 meaning
  // 1 ray cast per pixel. If set to 0.5, 4 rays will be cast per pixel. If
  // set to 2.0, 1 ray will be cast for every 4 (2 by 2) pixels. This value
  // will be adjusted to meet a desired frame rate when AutoAdjustSampleDistances
  // is on.
  vtkSetClampMacro( ImageSampleDistance, float, 0.1f, 100.0f );
  vtkGetMacro( ImageSampleDistance, float );

  // Description:
  // This is the minimum image sample distance allow when the image
  // sample distance is being automatically adjusted.
  vtkSetClampMacro( MinimumImageSampleDistance, float, 0.1f, 100.0f );
  vtkGetMacro( MinimumImageSampleDistance, float );

  // Description:
  // This is the maximum image sample distance allow when the image
  // sample distance is being automatically adjusted.
  vtkSetClampMacro( MaximumImageSampleDistance, float, 0.1f, 100.0f );
  vtkGetMacro( MaximumImageSampleDistance, float );


  // Description:
  // Set/Get the window / level applied to the final color.
  // This allows brightness / contrast adjustments on the
  // final image.
  // window is the width of the window.
  // level is the center of the window.
  // Initial window value is 1.0
  // Initial level value is 0.5
  // window cannot be null but can be negative, this way
  // values will be reversed.
  // |window| can be larger than 1.0
  // level can be any real value.
  vtkSetMacro( FinalColorWindow, float );
  vtkGetMacro( FinalColorWindow, float );
  vtkSetMacro( FinalColorLevel,  float );
  vtkGetMacro( FinalColorLevel,  float );

  // Description:
  // Maximum size of the 3D texture in GPU memory.
  // Will default to the size computed from the graphics
  // card. Can be adjusted by the user.
  vtkSetMacro( MaxMemoryInBytes, vtkIdType );
  vtkGetMacro( MaxMemoryInBytes, vtkIdType );

  // Description:
  // Maximum fraction of the MaxMemoryInBytes that should
  // be used to hold the texture. Valid values are 0.1 to
  // 1.0.
  vtkSetClampMacro( MaxMemoryFraction, float, 0.1f, 1.0f );
  vtkGetMacro( MaxMemoryFraction, float );

  // Description:
  // Tells if the mapper will report intermediate progress.
  // Initial value is true. As the progress works with a GL blocking
  // call (glFinish()), this can be useful for huge dataset but can
  // slow down rendering of small dataset. It should be set to true
  // for big dataset or complex shading and streaming but to false for
  // small datasets.
  vtkSetMacro(ReportProgress,bool);
  vtkGetMacro(ReportProgress,bool);

  // Description:
  // Based on hardware and properties, we may or may not be able to
  // render using 3D texture mapping. This indicates if 3D texture
  // mapping is supported by the hardware, and if the other extensions
  // necessary to support the specific properties are available.
  virtual int IsRenderSupported(vtkRenderWindow *vtkNotUsed(window),
                                vtkVolumeProperty *vtkNotUsed(property))
    {
      return 0;
    }

  void CreateCanonicalView( vtkRenderer *ren,
                            vtkVolume *volume,
                            vtkImageData *image,
                            int blend_mode,
                            double viewDirection[3],
                            double viewUp[3] );

  // Description:
  // Optionally, set a mask input. This mask may be a binary mask or a label
  // map. This must be specified via SetMaskType.
  //
  // If the mask is a binary mask, the volume rendering is confined to regions
  // within the binary mask. The binary mask is assumed to have a datatype of
  // UCHAR and values of 255 (inside) and 0 (outside).
  //
  // The mask may also be a label map. The label map is allowed to contain only
  // 3 labels (values of 0, 1 and 2) and must have a datatype of UCHAR. In voxels
  // with label value of 0, the color transfer function supplied by component
  // 0 is used.
  //   In voxels with label value of 1, the color transfer function supplied by
  // component 1 is used and blended with the transfer function supplied by
  // component 0, with the blending weight being determined by
  // MaskBlendFactor.
  //    In voxels with a label value of 2, the color transfer function supplied
  //  by component 2 is used and blended with the transfer function supplied by
  // component 0, with the blending weight being determined by
  // MaskBlendFactor.
  void SetMaskInput(vtkImageData *mask);
  vtkGetObjectMacro(MaskInput, vtkImageData);

  //BTX
  enum { BinaryMaskType = 0, LabelMapMaskType };
  //ETX

  // Description:
  // Set the mask type, if mask is to be used. See documentation for
  // SetMaskInput(). The default is a LabelMapMaskType.
  vtkSetMacro( MaskType, int );
  vtkGetMacro( MaskType, int );
  void SetMaskTypeToBinary();
  void SetMaskTypeToLabelMap();

  // Description:
  // Tells how much mask color transfer function is used compared to the
  // standard color transfer function when the mask is true. This is relevant
  // only for the label map mask.
  //   0.0 means only standard color transfer function.
  //   1.0 means only mask color transfer function.
  // The default value is 1.0.
  vtkSetClampMacro(MaskBlendFactor,float,0.0f,1.0f);
  vtkGetMacro(MaskBlendFactor,float);

  // Description:
  // Enable or disable setting output of volume rendering to be
  // color and depth textures. By default this is set to 0 (off).
  // It should be noted that it is possible that underlying API specific
  // mapper may not supoport RenderToImage mode.
  vtkSetMacro(RenderToImage, int);
  vtkGetMacro(RenderToImage, int);
  vtkBooleanMacro(RenderToImage, int);

  // Description:
  // Low level API to export the depth texture as vtkImageData in
  // RenderToImage mode.
  // Should be implemented by the graphics API specific mapper (GL or other).
  virtual void GetDepthImage(vtkImageData*) {};

  // Description:
  // Low level API to export the color texture as vtkImageData in
  // RenderToImage mode.
  // Should be implemented by the graphics API specific mapper (GL or other).
  virtual void GetColorImage(vtkImageData*) {};

//BTX
  // Description:
  // WARNING: INTERNAL METHOD - NOT INTENDED FOR GENERAL USE
  // Initialize rendering for this volume.
  void Render( vtkRenderer *, vtkVolume * );

  // Description:
  // Handled in the subclass - the actual render method
  // \pre input is up-to-date.
  virtual void GPURender( vtkRenderer *, vtkVolume *) {}

  // Description:
  // WARNING: INTERNAL METHOD - NOT INTENDED FOR GENERAL USE
  // Release any graphics resources that are being consumed by this mapper.
  // The parameter window could be used to determine which graphic
  // resources to release.
  void ReleaseGraphicsResources(vtkWindow *) {}

  // Description:
  // Return how much the dataset has to be reduced in each dimension to
  // fit on the GPU. If the value is 1.0, there is no need to reduce the
  // dataset.
  // \pre the calling thread has a current OpenGL context.
  // \pre mapper_supported: IsRenderSupported(renderer->GetRenderWindow(),0)
  // The computation is based on hardware limits (3D texture indexable size)
  // and MaxMemoryInBytes.
  // \post valid_i_ratio: ratio[0]>0 && ratio[0]<=1.0
  // \post valid_j_ratio: ratio[1]>0 && ratio[1]<=1.0
  // \post valid_k_ratio: ratio[2]>0 && ratio[2]<=1.0
  virtual void GetReductionRatio(double ratio[3])=0;

//ETX

protected:
  vtkGPUVolumeRayCastMapper();
  ~vtkGPUVolumeRayCastMapper();

  // Check to see that the render will be OK
  int ValidateRender( vtkRenderer *, vtkVolume * );


  // Special version of render called during the creation
  // of a canonical view.
  void CanonicalViewRender( vtkRenderer *, vtkVolume * );

  // Methods called by the AMR Volume Mapper.
  virtual void PreRender(vtkRenderer *ren,
                         vtkVolume *vol,
                         double datasetBounds[6],
                         double scalarRange[2],
                         int numberOfScalarComponents,
                         unsigned int numberOfLevels)=0;

  // \pre input is up-to-date
  virtual void RenderBlock(vtkRenderer *ren,
                           vtkVolume *vol,
                           unsigned int level)=0;

  virtual void PostRender(vtkRenderer *ren,
                          int numberOfScalarComponents)=0;

  // Description:
  // Called by the AMR Volume Mapper.
  // Set the flag that tells if the scalars are on point data (0) or
  // cell data (1).
  void SetCellFlag(int cellFlag);

  int    AutoAdjustSampleDistances;
  float  ImageSampleDistance;
  float  MinimumImageSampleDistance;
  float  MaximumImageSampleDistance;

  // Render to texture mode flag
  int RenderToImage;

  // Enable / disable stochasting jittering
  int UseJittering;

  // The distance between sample points along the ray
  float  SampleDistance;

  int    SmallVolumeRender;
  double BigTimeToDraw;
  double SmallTimeToDraw;

  float FinalColorWindow;
  float FinalColorLevel;

  // 1 if we are generating the canonical image, 0 otherwise
  int   GeneratingCanonicalView;
  vtkImageData *CanonicalViewImageData;

  // Description:
  // Set the mapper in AMR Mode or not. Initial value is false.
  // Called only by the vtkKWAMRVolumeMapper
  vtkSetClampMacro(AMRMode,int,0,1);
  vtkGetMacro(AMRMode,int);
  vtkBooleanMacro(AMRMode,int);

  vtkImageData * MaskInput;
  float          MaskBlendFactor;
  int            MaskType;

  int AMRMode;

  // Point data or cell data (or field data, not handled) ?
  int CellFlag;

  // Description:
  // Compute the cropping planes clipped by the bounds of the volume.
  // The result is put into this->ClippedCroppingRegionPlanes.
  // NOTE: IT WILL BE MOVED UP TO vtkVolumeMapper after bullet proof usage
  // in this mapper. Other subclasses will use the ClippedCroppingRegionsPlanes
  // members instead of CroppingRegionPlanes.
  // \pre volume_exists: this->GetInput()!=0
  // \pre valid_cropping: this->Cropping &&
  //             this->CroppingRegionPlanes[0]<this->CroppingRegionPlanes[1] &&
  //             this->CroppingRegionPlanes[2]<this->CroppingRegionPlanes[3] &&
  //             this->CroppingRegionPlanes[4]<this->CroppingRegionPlanes[5])
  virtual void ClipCroppingRegionPlanes();

  double         ClippedCroppingRegionPlanes[6];

  vtkIdType MaxMemoryInBytes;
  float MaxMemoryFraction;

  bool           ReportProgress;

  vtkImageData * TransformedInput;

  vtkGetObjectMacro(TransformedInput, vtkImageData);
  void SetTransformedInput(vtkImageData*);

  // Description:
  // This is needed only to check if the input data has been changed since the last
  // Render() call.
  vtkImageData* LastInput;

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

#endif