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histo.h

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

#ifndef histoH
#define histoH
//---------------------------------------------------------------------------

#include <Classes.hpp>
#include <Controls.hpp>
#include <ExtCtrls.hpp>
#include <assert.h>
#include <math.h>

#define MAX(x,y)        (((x)>(y)) ? (x) : (y))

class THistogram {

private:
        int *_histo;
        int _size;
        int _max;
        bool _maxDirty;
        bool _drawAverage;
        bool _horizontal;
        TColor _fg, _bg;
        float _histoZoom;       // 1 means, the whole histogram will be
        float _valZoom;         // plotted; any value greater 1 is a "zoom in";
                                // values between 0 and 1 are "zoom out";
        float _histoPos;        // 0 means centered; <0 window moved to the
        float _valPos;          // left, >0 window moved to the right
        int _logType;           // 0=linear, 1=ld, 2=log10

        void __fastcall __drawLine(TPaintBox *pb, int val, int line);
        float __fastcall MYLOG(float val)
        {
                switch(_logType)
                {
                        case 1:
                                return log(val);
                        case 2:
                                return log10(val);
                        default:
                                return val;
                }
        }

public:
        THistogram(int size);
        ~THistogram() {
                delete [] _histo;
        }

        __property bool drawAverage = { read=_drawAverage, write=_drawAverage };
        __property bool horizontal = { read=_horizontal, write=_horizontal };
        __property TColor foreground = { read=_fg, write=_fg };
        __property TColor background = { read=_bg, write=_bg };
        __property float histoZoom = { read=_histoZoom, write=_histoZoom };
        __property float valZoom = { read=_valZoom, write=_valZoom };
        __property float histoPos = { read=_histoPos, write=_histoPos };
        __property float valPos = { read=_valPos, write=_valPos };
        __property int logType = { read=_logType, write=_logType };
        __property int size = { read=_size, write=_size };

        void __fastcall drawTo(TPaintBox *pb);

        float __fastcall getHPP(TPaintBox *pb);    // Histos per pixel
        float __fastcall getVPP(TPaintBox *pb);    // Values per pixel

        float __fastcall getHMaxZoom(TControl *pb);

        int __fastcall calcMax()
        {
                if (_maxDirty) {
                        for(int i=0; i<_size; ++i)
                                _max=MAX(_max, _histo[i]);
                        _maxDirty = false;
                }
                return _max;
        }

        int &operator[](int n) {
                //assert(n>=0 && n<_size);
                if (n<0 || n>=_size) {
                        return _histo[0];
                } else {
                        _maxDirty = true;
                        return _histo[n];
                }
        }
};

#endif

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