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histo.cpp

//---------------------------------------------------------------------------


#pragma hdrstop

#include "histo.h"

//---------------------------------------------------------------------------

#pragma package(smart_init)

THistogram::THistogram(int size)
:
        _size(size),
        _max(0),
        _maxDirty(true),
        _drawAverage(false),
        _horizontal(true),
        _fg(clLtGray),
        _bg(clWhite),
        _histoZoom(1.0),
        _valZoom(1.0),
        _histoPos(0.0),
        _valPos(0.0),
        _logType(2)
{
        _histo = new int[size];
        memset((void*)_histo, 0, _size*sizeof(int));
}

void __fastcall THistogram::__drawLine(TPaintBox *pb, int val, int line)
{
        if (val != 0)
        {
                TCanvas *c = pb->Canvas;
                float _vpp = getVPP(pb);
                int len = (int)(MYLOG(val)/_vpp);
                c->Pen->Color = _fg;
                if (_horizontal) {
                        c->MoveTo(line, pb->Height-len);
                        c->LineTo(line, pb->Height);
                } else {
                        c->MoveTo(pb->Width-len, line);
                        c->LineTo(pb->Width, line);
                }
        }
}

float __fastcall THistogram::getHPP(TPaintBox *pb)
{
        int w = _horizontal ? pb->Width : pb->Height;
        if (w == 0) return 1.0;
        else        return ((float)_size/(float)w);
        //else        return ((float)_size/(float)w/_histoZoom);
}

float __fastcall THistogram::getVPP(TPaintBox *pb)
{
        int h = _horizontal ? pb->Height : pb->Width;
        if (h == 0) return 1.0;
        else        return (MYLOG(calcMax())/(float)h);
        //else        return (MYLOG(calcMax())/(float)h/_valZoom);
}

float __fastcall THistogram::getHMaxZoom(TControl *pb)
{
        int w = _horizontal ? pb->Width : pb->Height;
        //return (((float)_size/2.0)+1.0)/(float)w;
        return ((float)_size/(float)w);
}

void __fastcall THistogram::drawTo(TPaintBox *pb)
{
        //float _hpp = getHPP(pb);

        //int count = 0;
        //long int valSum = 0;
        //int valMax = 0;
        TCanvas *c = pb->Canvas;

        c->FillRect(pb->ClientRect);
        pb->Color = _bg;

        /*
        for(int i = 1; i<4096; ++i)     // do not pay attantion on number of
                                        // zeros.
        {
                if (!(i%(int)_hpp)) {
                        if (_drawAverage)
                                __drawLine(pb, (float)valSum/(float)count,
                                           i/(int)_hpp);
                        else
                                __drawLine(pb, (float)valMax,
                                           i/(int)_hpp);
                        count = 1;
                        valSum = _histo[i];
                        valMax = _histo[i];
                } else {
                        count++;
                        valSum += _histo[i];
                        valMax = MAX(valMax, _histo[i]);
                }
        }
        */
        int max;
        if (_horizontal) max=pb->Width;
        else             max=pb->Height;
        for(int i = 1; i<max; ++i)
        {
                int j = (int)((float)(i-1)*getHPP(pb));
                int end = (int)((float)i*getHPP(pb));
                //int dist = end-i;
                int sum = 0;
                for(; j<end; ++j)
                        sum = MAX(sum, _histo[j]);
                //__drawLine(pb, (float)sum/(float)dist,i);
                __drawLine(pb, sum,i);

        }
}

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