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

  Program:   Visualization Toolkit
  Module:    vtkVolumeRayCastCompositeFunction.h
  Language:  C++
  Date:      $Date$
  Version:   $Revision$


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.

=========================================================================*/
// .NAME vtkVolumeRayCastCompositeFunction - a ray function for compositing

// .SECTION Description
// vtkVolumeRayCastCompositeFunction is a ray function that can be used
// within a vtkVolumeRayCastMapper. This function performs compositing along
// the ray according to the properties stored in the vtkVolumeProperty for
// the volume. 

// .SECTION See Also
// vtkVolumeRayCastMapper vtkVolumeProperty vtkVolume

#ifndef __vtkVolumeRayCastCompositeFunction_h
#define __vtkVolumeRayCastCompositeFunction_h

#include "vtkVolumeRayCastFunction.h"

#define VTK_COMPOSITE_CLASSIFY_FIRST 0
#define VTK_COMPOSITE_INTERPOLATE_FIRST 1

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

  // Description:
  // Set the CompositeMethod to either Classify First or Interpolate First
  vtkSetClampMacro( CompositeMethod, int,
        VTK_COMPOSITE_CLASSIFY_FIRST, VTK_COMPOSITE_INTERPOLATE_FIRST );
  vtkGetMacro(CompositeMethod,int);
  void SetCompositeMethodToInterpolateFirst()
    {this->SetCompositeMethod(VTK_COMPOSITE_INTERPOLATE_FIRST);}
  void SetCompositeMethodToClassifyFirst() 
    {this->SetCompositeMethod(VTK_COMPOSITE_CLASSIFY_FIRST);}
  const char *GetCompositeMethodAsString(void);

//BTX
  void CastRay( VTKVRCDynamicInfo *dynamicInfo,
                VTKVRCStaticInfo *staticInfo);

  float GetZeroOpacityThreshold( vtkVolume *vol );
//ETX

protected:
  vtkVolumeRayCastCompositeFunction();
  ~vtkVolumeRayCastCompositeFunction();

//BTX
  void SpecificFunctionInitialize( vtkRenderer *ren,
                                   vtkVolume   *vol,
                                   VTKVRCStaticInfo *staticInfo,
                                   vtkVolumeRayCastMapper *mapper );
//ETX
  
  int           CompositeMethod;
private:
  vtkVolumeRayCastCompositeFunction(const vtkVolumeRayCastCompositeFunction&);  // Not implemented.
  void operator=(const vtkVolumeRayCastCompositeFunction&);  // Not implemented.
};


#endif
