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39
40#include "qcolortrclut_p.h"
41#include "qcolortransferfunction_p.h"
42#include "qcolortransfertable_p.h"
43#include <qmath.h>
44
45QT_BEGIN_NAMESPACE
46
47QColorTrcLut *QColorTrcLut::fromGamma(qreal gamma)
48{
49 QColorTrcLut *cp = new QColorTrcLut;
50
51 for (int i = 0; i <= (255 * 16); ++i) {
52 cp->m_toLinear[i] = ushort(qRound(qPow(i / qreal(255 * 16), gamma) * (255 * 256)));
53 cp->m_fromLinear[i] = ushort(qRound(qPow(i / qreal(255 * 16), qreal(1) / gamma) * (255 * 256)));
54 }
55
56 return cp;
57}
58
59QColorTrcLut *QColorTrcLut::fromTransferFunction(const QColorTransferFunction &fun)
60{
61 QColorTrcLut *cp = new QColorTrcLut;
62 QColorTransferFunction inv = fun.inverted();
63
64 for (int i = 0; i <= (255 * 16); ++i) {
65 cp->m_toLinear[i] = ushort(qRound(fun.apply(i / qreal(255 * 16)) * (255 * 256)));
66 cp->m_fromLinear[i] = ushort(qRound(inv.apply(i / qreal(255 * 16)) * (255 * 256)));
67 }
68
69 return cp;
70}
71
72QColorTrcLut *QColorTrcLut::fromTransferTable(const QColorTransferTable &table)
73{
74 QColorTrcLut *cp = new QColorTrcLut;
75
76 float minInverse = 0.0f;
77 for (int i = 0; i <= (255 * 16); ++i) {
78 cp->m_toLinear[i] = ushort(qBound(0, qRound(table.apply(i / qreal(255 * 16)) * (255 * 256)), 65280));
79 minInverse = table.applyInverse(i / qreal(255 * 16), minInverse);
80 cp->m_fromLinear[i] = ushort(qBound(0, qRound(minInverse * (255 * 256)), 65280));
81 }
82
83 return cp;
84}
85
86QT_END_NAMESPACE
87