source: GTP/trunk/Lib/Vis/Preprocessing/src/RayCaster.h @ 2048

#ifndef _RayCaster_H__
#define _RayCaster_H__

#include "Containers.h"
#include <string>
#include "Vector3.h"
#include "VssRay.h"

using namespace std;


namespace GtpVisibilityPreprocessor {


class Intersectable;
class VssRay;
class SimpleRayContainer;
class AxisAlignedBox3;
//class Vector3;
struct VssRayContainer;
class Preprocessor;
struct SimpleRay;


/** This class provides an interface for ray casting.
*/
class RayCaster
{

public:
        
        enum {
          INTERNAL_RAYCASTER = 0,
          INTEL_RAYCASTER
        };

        RayCaster(const Preprocessor &preprocessor);

        virtual ~RayCaster();

        virtual int Type() const = 0;

        /** Wrapper for casting single ray.
                @returns ray or NULL if invalid
        */
        VssRay *CastRay(const SimpleRay &simpleRay,
                                        const AxisAlignedBox3 &box,
                                        const bool castDoubleRay);

        virtual int CastRay(const SimpleRay &simpleRay,
                                                VssRayContainer &vssRays,
                                                const AxisAlignedBox3 &box,
                                                const bool castDoubleRay,
                                                const bool pruneInvalidRays = true) = 0;

        virtual void CastRays16(
                                                         SimpleRayContainer &rays,
                                                         VssRayContainer &vssRays,
                                                         const AxisAlignedBox3 &sbox,
                                                         const bool castDoubleRay,
                                                         const bool pruneInvalidRays = true) = 0;


  virtual void
  SortRays(SimpleRayContainer &rays);



  // pool of vss rays to be used in one pass of the sampling
  struct VssRayPool {
        VssRayPool():mRays(NULL), mIndex(0), mNumber(0) {}
        ~VssRayPool() {
          if (mRays)
                delete mRays;
        }
        
        void Reserve(const int number) {
          if (mRays)
                delete mRays;
          mRays = new VssRay[number];
          mNumber = number;
        }
        
        void Clear() {
          mIndex = 0;
        }
        VssRay *Alloc() {
                // reset pool
                if (mIndex == mNumber)
                        mIndex = 0;
          return mRays + mIndex++;
        }

        VssRay *mRays;
        int mIndex;
        int mNumber;
  };

  
  VssRayPool mVssRayPool;

  void ReserveVssRayPool(const int n) {
        mVssRayPool.Reserve(n);
  }
  
  void InitPass() {
        mVssRayPool.Clear();
  }


protected:
  void _SortRays(SimpleRayContainer &rays,
                                 const int l,
                                 const int r,
                                 const int depth,
                                 float box[12]);
        
  struct Intersection
        {
                Intersection(): mObject(NULL), mFaceId(0)
                {}

                Intersection(const Vector3 &p, const Vector3 &n, Intersectable *o, const int f):
                        mPoint(p), mNormal(n), mObject(o), mFaceId(f)
                {}

                Intersection(const Vector3 &p): mPoint(p), mObject(NULL), mFaceId(0)
                {}
                Vector3 mPoint;
                Vector3 mNormal;
                Intersectable *mObject;
                int mFaceId;
        };


        int ProcessRay(const SimpleRay &ray,
                                   Intersection &hitA,
                                   Intersection &hitB,
                                   VssRayContainer &vssRays,
                                   const AxisAlignedBox3 &box,
                                   const bool castDoubleRay,
                                   const bool pruneInvalidRays = true);

        /** Checks if ray is valid.
                I.e., the ray is in valid view space.
                @note: clamps the ray to valid view space.
        */
        bool ValidateRay(const Vector3 &origin,
                                         const Vector3 &direction,
                                 const AxisAlignedBox3 &box,
                                         Intersection &hit);

        bool
                ClipToViewSpaceBox(const Vector3 &origin,
                                                   const Vector3 &termination,
                                                   Vector3 &clippedOrigin,
                                                   Vector3 &clippedTermination);
        



  

  const Preprocessor &mPreprocessor;
};


}

#endif