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Rendering/vtkVolumeRayCastMapper.h

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

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkVolumeRayCastMapper.h,v $
  Language:  C++


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.

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

#ifndef __vtkVolumeRayCastMapper_h
#define __vtkVolumeRayCastMapper_h

#include "vtkVolumeMapper.h"
#include "vtkMultiThreader.h"
#include "vtkVolumeRayCastFunction.h"
#include "vtkEncodedGradientShader.h"
#include "vtkEncodedGradientEstimator.h"

class  vtkRenderer;
class  vtkVolume;
class  vtkVolumeTransform;
class  vtkPlaneCollection;
class  vtkPoints;
class  vtkCellArray;
class  vtkTCoords;
class  vtkPolyData;
class  vtkTexture;
class  vtkActor;
class  vtkPolyDataMapper;
class  vtkMultiThreader;
class  vtkTimerLog;

// Macro for floor of x
#define vtkFloorFuncMacro(x)   (((x) < 0.0)?((int)((x)-1.0)):((int)(x)))

// Macro for rounding x
#define vtkRoundFuncMacro(x)   (int)((x)+0.5)

// Macro for tri-linear 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   =  t0 + (z)*(t1-t0);

class VTK_RENDERING_EXPORT vtkVolumeRayCastMapper : public vtkVolumeMapper
{
public:
  static vtkVolumeRayCastMapper *New();
  vtkTypeMacro(vtkVolumeRayCastMapper,vtkVolumeMapper);
  void PrintSelf( ostream& os, vtkIndent index );


  vtkSetMacro( SampleDistance, float );
  vtkGetMacro( SampleDistance, float );


  vtkSetObjectMacro( VolumeRayCastFunction, vtkVolumeRayCastFunction );
  vtkGetObjectMacro( VolumeRayCastFunction, vtkVolumeRayCastFunction );


  void SetGradientEstimator( vtkEncodedGradientEstimator *gradest );
  vtkGetObjectMacro( GradientEstimator, vtkEncodedGradientEstimator );


  vtkGetObjectMacro( GradientShader, vtkEncodedGradientShader );


  vtkSetClampMacro( ImageSampleDistance, float, 0.1, 100.0 );
  vtkGetMacro( ImageSampleDistance, float );


  vtkSetClampMacro( MinimumImageSampleDistance, float, 0.1, 100.0 );
  vtkGetMacro( MinimumImageSampleDistance, float );


  vtkSetClampMacro( MaximumImageSampleDistance, float, 0.1, 100.0 );
  vtkGetMacro( MaximumImageSampleDistance, float );


  vtkSetClampMacro( AutoAdjustSampleDistances, int, 0, 1 );
  vtkGetMacro( AutoAdjustSampleDistances, int );
  vtkBooleanMacro( AutoAdjustSampleDistances, int );
  

  void SetNumberOfThreads( int num );
  vtkGetMacro( NumberOfThreads, int );


  vtkSetClampMacro( IntermixIntersectingGeometry, int, 0, 1 );
  vtkGetMacro( IntermixIntersectingGeometry, int );
  vtkBooleanMacro( IntermixIntersectingGeometry, int );
  
//BTX
  void Render( vtkRenderer *, vtkVolume * );

  void ReleaseGraphicsResources(vtkWindow *);

  float GetZeroOpacityThreshold( vtkVolume *vol );


  virtual float GetGradientMagnitudeScale();
  virtual float GetGradientMagnitudeBias();
  
//ETX

protected:
  vtkVolumeRayCastMapper();
  ~vtkVolumeRayCastMapper();

  vtkVolumeRayCastFunction     *VolumeRayCastFunction;
  vtkEncodedGradientEstimator  *GradientEstimator;
  vtkEncodedGradientShader     *GradientShader;

  // The distance between sample points along the ray
  float                        SampleDistance;
  float                        ImageSampleDistance;
  float                        MinimumImageSampleDistance;
  float                        MaximumImageSampleDistance;
  int                          AutoAdjustSampleDistances;
  
  float                        WorldSampleDistance;
  int                          ScalarDataType;
  void                         *ScalarDataPointer;

  void                         UpdateShadingTables( vtkRenderer *ren, 
                                                    vtkVolume *vol );

  void ComputeMatrices( vtkImageData *data, vtkVolume *vol );
  virtual void RenderTexture( vtkVolume *vol, vtkRenderer *ren)=0;
  int ComputeRowBounds( vtkVolume *vol, vtkRenderer *ren );
  
  friend VTK_THREAD_RETURN_TYPE VolumeRayCastMapper_CastRays( void *arg );

  vtkMultiThreader  *Threader;
  int               NumberOfThreads;

  vtkMatrix4x4 *PerspectiveMatrix;
  vtkMatrix4x4 *ViewToWorldMatrix;
  vtkMatrix4x4 *ViewToVoxelsMatrix;
  vtkMatrix4x4 *VoxelsToViewMatrix;
  vtkMatrix4x4 *WorldToVoxelsMatrix;
  vtkMatrix4x4 *VoxelsToWorldMatrix;
  
  // This is how big the image would be if it covered the entire viewport
  int            ImageViewportSize[2];
  
  // This is how big the allocated memory for image is. This may be bigger
  // or smaller than ImageFullSize - it will be bigger if necessary to 
  // ensure a power of 2, it will be smaller if the volume only covers a
  // small region of the viewport
  int            ImageMemorySize[2];
  
  // This is the size of subregion in ImageSize image that we are using for
  // the current image. Since ImageSize is a power of 2, there is likely
  // wasted space in it. This number will be used for things such as clearing
  // the image if necessary.
  int            ImageInUseSize[2];
  
  // This is the location in ImageFullSize image where our ImageSize image
  // is located.
  int            ImageOrigin[2];
  
  // This is the allocated image
  unsigned char *Image;
  
  int  *RowBounds;
  int  *OldRowBounds;

  float        *RenderTimeTable;
  vtkVolume   **RenderVolumeTable;
  vtkRenderer **RenderRendererTable;
  int           RenderTableSize;
  int           RenderTableEntries;

  void StoreRenderTime( vtkRenderer *ren, vtkVolume *vol, float t );
  float RetrieveRenderTime( vtkRenderer *ren, vtkVolume *vol );

  int           IntermixIntersectingGeometry;

  float        *ZBuffer;
  int           ZBufferSize[2];
  int           ZBufferOrigin[2];

  float         MinimumViewDistance;
  
  int           ClipRayAgainstVolume( VTKVRCDynamicInfo *dynamicInfo,
                                      float bounds[6] );

  void          InitializeClippingPlanes( VTKVRCStaticInfo *staticInfo,
                                          vtkPlaneCollection *planes );

  int           ClipRayAgainstClippingPlanes( VTKVRCDynamicInfo *dynamicInfo,
                                              VTKVRCStaticInfo *staticInfo);
  
  // Get the ZBuffer value corresponding to location (x,y) where (x,y)
  // are indexing into the ImageInUse image. This must be converted to
  // the zbuffer image coordinates. Nearest neighbor value is returned.
  float         GetZBufferValue( int x, int y );

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

#endif

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