source: GTP/trunk/Lib/Vis/Preprocessing/EvalStats/EvalStats.cpp @ 1291

// EvalStats.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"

#include <string>
#include <vector>
#include <istream>
#include <iostream>
#include <fstream>
#include <math.h>
#include <algorithm>

using namespace std;



/** This is a small function which takes two log files and computes the
        difference in percent of the weighted render cost.
*/
struct RenderStats 
{
        float mRenderCost;
        float mAvgRenderCost;
};


typedef vector<RenderStats> StatsContainer;


enum {NO_TAG, RENDER_COST, AVG_RENDER_COST};


bool extractRenderStats(ifstream &file, StatsContainer &renderStats)
{
        if (!file.is_open())
                return false;
                
        string buf;

        int currentTag = NO_TAG;

        while (!(getline(file, buf)).eof())
        {
                //cout << "buf: " << buf << endl;

                if (buf[0] == '#')
                {
                        char entry[50]; 

                        sscanf(buf.c_str(), "#%s", entry);
                        
                        // new entry
                        if (strcmp(entry, "Pass") == 0)
                        {
                                //cout << "\nnew render stat " << endl;
                                renderStats.push_back(RenderStats());
                        }
                        else if (strcmp(entry, "TotalRenderCost") == 0)
                        {
                                currentTag = RENDER_COST;
                        }
                        else if (strcmp(entry, "AvgRenderCost") == 0)
                        {
                                currentTag = AVG_RENDER_COST;
                        }
                }
                else
                {
                        float val;
                        sscanf(buf.c_str(), "%f", &val);
                        
                        switch (currentTag)
                        {
                        case RENDER_COST:
                                //cout << "render cost: " << val << endl;
                renderStats.back().mRenderCost = val;
                                break;
                        case AVG_RENDER_COST:
                                //cout << "avg render cost: " << val << endl;
                                renderStats.back().mAvgRenderCost = val;
                                break;
                        default:
                                break;
                        }
                        
                        currentTag = NO_TAG;
                }
        }

        return true;
}



void ComputeStats(ofstream &statsOut, 
                                  const RenderStats &firstStats, 
                                  const RenderStats &currentStats, 
                                  const int index)
{
        float denom = firstStats.mRenderCost ? firstStats.mRenderCost : 0.000001f;
        float costRatio = currentStats.mRenderCost / denom;
                        
        denom = firstStats.mAvgRenderCost ? firstStats.mAvgRenderCost : 0.000001f;
        float avgCostRatio = currentStats.mAvgRenderCost / denom;

        statsOut << "#ViewCells\n" << index + 1 << endl
                         << "#TotalRenderCostRatio\n" << costRatio << endl
                         << "#AvgRenderCostRatio\n" << avgCostRatio << endl << endl;
}


inline bool vlt(const RenderStats &c1, const RenderStats &c2)
{
        return c1.mRenderCost > c2.mRenderCost;
}


// evaluate number of view cells needed for same rendercost
void EvalNumViewCells(ofstream &outstream,
                                          const StatsContainer &firstStats, 
                                          const StatsContainer &currentStats)
{
        
        const int n = min((int)firstStats.size(), (int)currentStats.size());
        //const int n = (int)firstStats.size();
        
        StatsContainer::const_iterator it, it_end = currentStats.end();

        int i = 0;

        // currentStats would be the other (necessarily worse?) method, firstStats would be our method
        // loop through view cells of currentStats
        // Compare render cost with render cost of other view cell
        // compute ratio of view cells
        for (it = currentStats.begin(); it != it_end; ++ it, ++ i)
        {
                
                const float renderCost = (*it).mRenderCost;
    
                // find equivalent render cost in the other stats container.
                // don't stop until cursor is placed one element behind
                // or end of vector is reached
                StatsContainer::const_iterator equalCostIt = std::upper_bound(firstStats.begin(), firstStats.end(), *it, vlt);

                int j = (int)(equalCostIt - firstStats.begin());

                float val;

                // special cases
                if (j == 0)
                {
                        val = (float)j;
                }
                else if (j >= n)
                {
                        val = (float)(j - 1);
                }
                else 
                // interpolate linearly. NOTE: probably big error because of steep curve
                // => intepolate logarithmically
                {
#if 1
                        const float rcu = log(firstStats[j - 1].mRenderCost);
                        const float rcl = log(firstStats[j].mRenderCost);
                        const float rc = log(renderCost);
#else
                        const float rcu = firstStats[j - 1].mRenderCost;
                        const float rcl = firstStats[j].mRenderCost;
                        const float rc = renderCost;
#endif
                        const float factor = (rcu - rcl != 0) ?
                                (rcu - rc) / (rcu - rcl) : 1;

                        // view cells needed for same render cost
                        val = (float)j - 1 + factor;
                }

                float ratio = (i && val) ? (float)i / val : 1;

                outstream << "#Pass\n" << i << endl;
                outstream << "#RenderCost\n" << renderCost << endl;
                outstream << "#ViewCellsRatio\n" << ratio << endl << endl;      
        }
}





// evaluate number of view cells needed for same rendercost
int EvalSingleNumViewCells(const StatsContainer &currentStats,
                                                   const float cost)
{
        
        StatsContainer::const_iterator it, it_end = currentStats.end();

        RenderStats dummy; dummy.mRenderCost = cost;
        
        // find equivalent render cost in the other stats container.
        // don't stop until cursor is placed one element behind
        // or end of vector is reached
        StatsContainer::const_iterator equalCostIt = std::upper_bound(currentStats.begin(),currentStats.end(), dummy, vlt);

        int j = (int)(equalCostIt - currentStats.begin());

        return j;
}



int _tmain(int argc, _TCHAR* argv[])
{
        vector<StatsContainer> renderStats;
        
        if (argc < 3)
        {
                cerr << "arguments missing. Usage: input1 input2 ... intputn" << endl;
                exit(1);
        }

        vector<string> outFilenames;
        vector<string> outFilenames2;
        vector<string> methodnames;
        // read input files from command line
        for (int i = 1; i < argc; ++ i)
        {
                StatsContainer currentStats;
      
                ifstream file;
                file.open(argv[i]);

                // extract the render cost
                cout << "extracting render cost of file " << argv[i] << endl;
        
                if (extractRenderStats(file, currentStats))
                {
                        renderStats.push_back(currentStats);

                        // create output file name
                        string fn = argv[i];
                
                        string::size_type pos = fn.find(".log", 0);
                        fn.erase(pos, 4);
                        //sscanf(argv[i], "%s.log", fn);
                        string outFilename = string(fn) + string("-ratio.log");
                        string outFilename2 = string(fn) + string("-reverse.log");
                        
                        outFilenames.push_back(outFilename);
                        outFilenames2.push_back(outFilename2);
                        methodnames.push_back(fn);

                        cout << "new filen: " << outFilename2 << endl;
                }
                else
                {
                        cout << "could not open file!" << endl;
                }
        }

        //statsOut << "rc1 size: " << (int)renderCosts1.size() << " " << (int)renderCosts2.size() << endl << endl;
        vector<StatsContainer>::const_iterator it = renderStats.begin(), it_end = renderStats.end();

        vector<string>::const_iterator sit, sit_end = outFilenames.end();
        vector<string>::const_iterator sit2, sit2_end = outFilenames2.end();
        vector<string>::const_iterator sit3, sit3_end = methodnames.end();


        sit = outFilenames.begin();
        sit2 = outFilenames2.begin();
        sit3 = methodnames.begin();

        // compare all values with this vector
        StatsContainer &firstStats = renderStats[0];

        // don't compare with itself
        //++ it;
        //++ sit;
        ofstream statsOut3;
        statsOut3.open("numviewcells.log");

        for (it; it != it_end; ++ it, ++ sit, ++ sit2, ++sit3)
        {
                cout << "now writing output to file " << *sit << endl;

                ofstream statsOut;
                statsOut.open((*sit).c_str());
        
                ofstream statsOut2;
                statsOut2.open((*sit2).c_str());

                cout << "opening new file: " << (*sit2).c_str() << endl;
                // compute size of output vector
                const int n = min((int)firstStats.size(), (int)(*it).size());
        
                for (int i = 0; i < n; ++ i)
                {
                        //cout << "rc: " << (*it)[i].mRenderCost << endl;
                        ComputeStats(statsOut, firstStats[i], (*it)[i], i);
                }

                // evaluate number of view cells needed for same rendercost
                EvalNumViewCells(statsOut2, firstStats, (*it));

                const float rendercost = 100;
                const int j = EvalSingleNumViewCells(*it, rendercost);

                statsOut3 << (*sit3).c_str() << " " << j << endl;

                statsOut.close();
                statsOut2.close();
        }

        statsOut3.close();



        return 0;
}