aboutsummaryrefslogtreecommitdiff
path: root/c++-qt/src/float.cpp
blob: d4ec76e0ec1e0130adfe794e4939cd946a5712c9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/*
 * Copyright (C) 2007-2013 Xagasoft, All rights reserved.
 *
 * This file is part of the libgats library and is released under the
 * terms of the license contained in the file LICENSE.
 */

#include "gats-qt/float.h"
#include "gats-qt/integer.h"

#include <math.h>

Gats::Float::Float() :
    fVal( 0.0 )
{
}

Gats::Float::Float( double f ) :
    fVal( f )
{
}

Gats::Float::~Float()
{
}

Gats::Object *Gats::Float::clone() const
{
    return new Gats::Float( fVal );
}

void Gats::Float::write( QIODevice &rOut ) const
{
    if( fVal == 0.0 )
    {
        if( signbit( fVal ) )
            rOut.write("FZ", 2 );
        else
            rOut.write("Fz", 2 );
    }
    else if( !isfinite( fVal ) )
    {
        if( isnan( fVal ) )
        {
            if( signbit( fVal ) )
                rOut.write("FN", 2 );
            else
                rOut.write("Fn", 2 );
        }
        else
        {
            if( signbit( fVal ) )
                rOut.write("FI", 2 );
            else
                rOut.write("Fi", 2 );
        }
    }
    else
    {
        rOut.write("f", 1 );
        double d = fVal;
        bool bNeg = false;
        int64_t iScale=0;
        if( signbit( d ) )
        {
            bNeg = true;
            d = -d;
        }

        iScale = log( d ) / 0x1.62e42fefa39efp+2; // log( 256.0 )
        if( iScale < 0 ) iScale--;
        d /= pow( 256.0, iScale );
        
        QByteArray s;
        s += (uint8_t)(d);
        d -= (int)d;
        for( int j = 0; j < 150 && d; j++ )
        {
            d = d*256.0;
            s += (uint8_t)d;
            d -= (int)d;
        }
        Gats::Integer::writePackedInt( rOut, bNeg?-s.size():s.size() );
        rOut.write( s.constData(), s.size() );
        Gats::Integer::writePackedInt( rOut, iScale );
    }
}

void Gats::Float::read( QIODevice &rIn, char cType )
{
    if( cType == 'F' )
    {
        char buf;
        rIn.read( &buf, 1 );
        switch( buf )
        {
            case 'N': fVal = -NAN;      break;
            case 'n': fVal = NAN;       break;
            case 'I': fVal = -INFINITY; break;
            case 'i': fVal = INFINITY;  break;
            case 'Z': fVal = -0.0;      break;
            case 'z': fVal = 0.0;       break;
        }
    }
    else if( cType == 'f' )
    {
        int64_t iStr;
        Gats::Integer::readPackedInt( rIn, iStr );
        bool bNeg = false;
        if( iStr < 0 )
        {
            bNeg = true;
            iStr = -iStr;
        }
        QByteArray s( iStr, '\0' );
        rIn.read( s.data(), iStr );
        fVal = 0.0;
        for( int j = iStr-1; j > 0; j-- )
        {
            fVal = (fVal+(uint8_t)s[j])*0x1p-8;
        }
        fVal += (uint8_t)s[0];
        int64_t iScale;
        Gats::Integer::readPackedInt( rIn, iScale );
        fVal *= pow( 256.0, iScale );
        if( bNeg ) fVal = -fVal;
    }
}

QString Gats::Float::toString( int /*iIndent*/ ) const
{
    return QString("%1").arg( fVal );
}

/*
Bu::Formatter &operator<<( Bu::Formatter &f, const Gats::Float &flt )
{
    return f << "(float) " << flt.getValue();
}*/