source: trunk/VUT/GtpVisibilityPreprocessor/src/Pvs.h @ 369

#ifndef __PVS_H
#define __PVS_H

#include <map>

class KdNode;
class BspNode;
class Ray;
class Intersectable;


template<typename T>
struct LtSample {
    bool operator()(const T a, const T b) const
    {
                return a < b;
        } 
};

//typedef std::map<T *, PvsData<T>, LtSample<T>> PvsMap<T>;

template<typename T> 
struct PvsData {
  int mVisibleSamples;
  PvsData<T>() {}
  PvsData<T>(const int samples): mVisibleSamples(samples) {}
};

template<typename T>
class Pvs
{
public:
        Pvs(): mSamples(0), mEntries() {}

        int mSamples;

        int Compress() {return 0;}
        int GetSize() {return (int)mEntries.size();}
        bool Empty() {return mEntries.size() == 0;}
        /** Merges pvs of a and pvs of b into this pvs.
        */
        void Merge(const Pvs<T> &a, const Pvs<T> &b);
    /** Difference of pvs to pvs b.
                @returns number of different entries.
        */
        int Diff(const Pvs<T> &b);

        PvsData<T> *Find(T sample);
        int AddSample(T sample);

        void GetData(const int index, T &entry, PvsData<T> &data);
        std::map<T, PvsData<T>, LtSample<T> > mEntries;
};

template <typename T>
int Pvs<T>::Diff(const Pvs<T> &b)
{
        int dif = 0;

        std::map<T, PvsData<T>, LtSample<T> >::const_iterator it;

        for (it = b.mEntries.begin(); it != b.mEntries.end(); ++ it)
        {
                PvsData<T> *data = Find((*it).first);           
                if (!data) ++ dif;
        }

        return dif;
}

template <typename T>
void Pvs<T>::Merge(const Pvs<T> &a, const Pvs<T> &b)
{
        std::map<T, PvsData<T>, LtSample<T> >::const_iterator it;

        // todo: copy all elements instead of inserting
        for (it = a.mEntries.begin(); it != a.mEntries.end(); ++ it)
        {
                mEntries.insert(*it);
        }

        for (it = b.mEntries.begin(); it != b.mEntries.end(); ++ it)
        {
                PvsData<T> *data = Find((*it).first);
                
                if (data)
                        data->mVisibleSamples += (*it).second.mVisibleSamples;
                else
                        mEntries.insert(*it);
        }
}


template <typename T>
PvsData<T> *Pvs<T>::Find(T sample)
{
  std::map<T, PvsData<T>, LtSample<T> >::iterator i = mEntries.find(sample);
  if (i != mEntries.end()) {
    return &(*i).second;
  } else
    return NULL;
}

template <typename T>
void Pvs<T>::GetData(const int index,
               T &entry,
               PvsData<T> &data)
{
  std::map<T, PvsData<T>, LtSample<T> >::iterator i = mEntries.begin();
  for (int k = 0; k != index && i != mEntries.end(); i++, k++);

  entry = (*i).first;
  data = (*i).second;
}

template <typename T>
int Pvs<T>::AddSample(T sample)
{
        int result;
        PvsData<T> *data = Find(sample);

        if (data) 
        {
                data->mVisibleSamples ++;
                result = 0;
        
        } 
        else 
        {
                mEntries[sample] = PvsData<T>(1);
                result = 1;
        }

        return  result;
}

/** Class instantiating the Pvs template for kd tree nodes.
*/
class KdPvs: public Pvs<KdNode *>
{
        int Compress();
};

typedef std::map<KdNode *, PvsData<KdNode *>, LtSample<KdNode *> > KdPvsMap;
typedef std::map<Intersectable *, PvsData<Intersectable *>, LtSample<Intersectable *> > ViewCellPvsMap;
typedef PvsData<Intersectable *> ViewCellPvsData;
typedef PvsData<KdNode *> KdPvsData;
//typedef Pvs<KdNode *> KdPvs;
typedef Pvs<Intersectable *> ViewCellPvs;


#endif