office-gobmx/tools/source/generic/fract.cxx
Luboš Luňák 3361db2179 include OutputDevice MapMode in SalLayoutGlyphsCache key (tdf#148400)
The mapmode also affects the layout of the glyphs.

Change-Id: I9492bc4d3d9e991ef8ab5dc30ce424e44cbc79f7
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/132822
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>
2022-04-12 13:31:09 +02:00

486 lines
14 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include <tools/fract.hxx>
#include <tools/debug.hxx>
#include <o3tl/hash_combine.hxx>
#include <o3tl/safeint.hxx>
#include <sal/log.hxx>
#include <osl/diagnose.h>
#include <algorithm>
#include <cmath>
#include <numeric>
#include <boost/rational.hpp>
#ifdef _MSC_VER
#include <intrin.h>
#endif
static boost::rational<sal_Int32> rational_FromDouble(double dVal);
static void rational_ReduceInaccurate(boost::rational<sal_Int32>& rRational, unsigned nSignificantBits);
static int impl_NumberOfBits( sal_uInt32 nNum );
static boost::rational<sal_Int32> toRational(sal_Int32 n, sal_Int32 d)
{
// https://github.com/boostorg/boost/issues/335 when these are std::numeric_limits<sal_Int32>::min
if (n == d)
return 1;
// tdf#144319 avoid boost::bad_rational e.g. if numerator=-476741369, denominator=-2147483648
if (d < -std::numeric_limits<sal_Int32>::max())
return 0;
return boost::rational<sal_Int32>(n, d);
}
// Initialized by setting nNum as nominator and nDen as denominator
// Negative values in the denominator are invalid and cause the
// inversion of both nominator and denominator signs
// in order to return the correct value.
Fraction::Fraction( sal_Int64 nNum, sal_Int64 nDen ) : mnNumerator(nNum), mnDenominator(nDen)
{
assert( nNum >= std::numeric_limits<sal_Int32>::min() );
assert( nNum <= std::numeric_limits<sal_Int32>::max( ));
assert( nDen >= std::numeric_limits<sal_Int32>::min() );
assert( nDen <= std::numeric_limits<sal_Int32>::max( ));
if ( nDen == 0 )
{
mbValid = false;
SAL_WARN( "tools.fraction", "'Fraction(" << nNum << ",0)' invalid fraction created" );
return;
}
if ((nDen == -1 && nNum == std::numeric_limits<sal_Int32>::min()) ||
(nNum == -1 && nDen == std::numeric_limits<sal_Int32>::min()))
{
mbValid = false;
SAL_WARN("tools.fraction", "'Fraction(" << nNum << "," << nDen << ")' invalid fraction created");
return;
}
}
/**
* only here to prevent passing of NaN
*/
Fraction::Fraction( double nNum, double nDen ) : mnNumerator(sal_Int64(nNum)), mnDenominator(sal_Int64(nDen))
{
assert( !std::isnan(nNum) );
assert( !std::isnan(nDen) );
assert( nNum >= std::numeric_limits<sal_Int32>::min() );
assert( nNum <= std::numeric_limits<sal_Int32>::max( ));
assert( nDen >= std::numeric_limits<sal_Int32>::min() );
assert( nDen <= std::numeric_limits<sal_Int32>::max( ));
if ( nDen == 0 )
{
mbValid = false;
SAL_WARN( "tools.fraction", "'Fraction(" << nNum << ",0)' invalid fraction created" );
return;
}
}
Fraction::Fraction( double dVal )
{
try
{
boost::rational<sal_Int32> v = rational_FromDouble( dVal );
mnNumerator = v.numerator();
mnDenominator = v.denominator();
}
catch (const boost::bad_rational&)
{
mbValid = false;
SAL_WARN( "tools.fraction", "'Fraction(" << dVal << ")' invalid fraction created" );
}
}
Fraction::operator double() const
{
if (!mbValid)
{
SAL_WARN( "tools.fraction", "'double()' on invalid fraction" );
return 0.0;
}
return boost::rational_cast<double>(toRational(mnNumerator, mnDenominator));
}
// This methods first validates both values.
// If one of the arguments is invalid, the whole operation is invalid.
// After computation detect if result overflows a sal_Int32 value
// which cause the operation to be marked as invalid
Fraction& Fraction::operator += ( const Fraction& rVal )
{
if ( !rVal.mbValid )
mbValid = false;
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'operator +=' with invalid fraction" );
return *this;
}
boost::rational<sal_Int32> a = toRational(mnNumerator, mnDenominator);
a += toRational(rVal.mnNumerator, rVal.mnDenominator);
mnNumerator = a.numerator();
mnDenominator = a.denominator();
return *this;
}
Fraction& Fraction::operator -= ( const Fraction& rVal )
{
if ( !rVal.mbValid )
mbValid = false;
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'operator -=' with invalid fraction" );
return *this;
}
boost::rational<sal_Int32> a = toRational(mnNumerator, mnDenominator);
a -= toRational(rVal.mnNumerator, rVal.mnDenominator);
mnNumerator = a.numerator();
mnDenominator = a.denominator();
return *this;
}
namespace
{
bool checked_multiply_by(boost::rational<sal_Int32>& i, const boost::rational<sal_Int32>& r)
{
// Protect against self-modification
sal_Int32 num = r.numerator();
sal_Int32 den = r.denominator();
// Fast-path if the number of bits in input is < the number of bits in the output, overflow cannot happen
// This is considerably faster than repeated std::gcd() operations
if ((impl_NumberOfBits(std::abs(i.numerator())) + impl_NumberOfBits(std::abs(r.numerator()))) < 32 &&
(impl_NumberOfBits(std::abs(i.denominator())) + impl_NumberOfBits(std::abs(r.denominator()))) < 32)
{
i *= r;
return false;
}
// Avoid overflow and preserve normalization
sal_Int32 gcd1 = std::gcd(i.numerator(), den);
sal_Int32 gcd2 = std::gcd(num, i.denominator());
if (!gcd1 || !gcd2)
return true;
bool fail = false;
fail |= o3tl::checked_multiply(i.numerator() / gcd1, num / gcd2, num);
fail |= o3tl::checked_multiply(i.denominator() / gcd2, den / gcd1, den);
if (!fail)
i.assign(num, den);
return fail;
}
}
Fraction& Fraction::operator *= ( const Fraction& rVal )
{
if ( !rVal.mbValid )
mbValid = false;
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'operator *=' with invalid fraction" );
return *this;
}
boost::rational<sal_Int32> a = toRational(mnNumerator, mnDenominator);
boost::rational<sal_Int32> b = toRational(rVal.mnNumerator, rVal.mnDenominator);
bool bFail = checked_multiply_by(a, b);
mnNumerator = a.numerator();
mnDenominator = a.denominator();
if (bFail)
{
mbValid = false;
}
return *this;
}
Fraction& Fraction::operator /= ( const Fraction& rVal )
{
if ( !rVal.mbValid )
mbValid = false;
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'operator /=' with invalid fraction" );
return *this;
}
boost::rational<sal_Int32> a = toRational(mnNumerator, mnDenominator);
a /= toRational(rVal.mnNumerator, rVal.mnDenominator);
mnNumerator = a.numerator();
mnDenominator = a.denominator();
return *this;
}
/** Inaccurate cancellation for a fraction.
Clip both nominator and denominator to said number of bits. If
either of those already have equal or less number of bits used,
this method does nothing.
@param nSignificantBits denotes, how many significant binary
digits to maintain, in both nominator and denominator.
@example ReduceInaccurate(8) has an error <1% [1/2^(8-1)] - the
largest error occurs with the following pair of values:
binary 1000000011111111111111111111111b/1000000000000000000000000000000b
= 1082130431/1073741824
= approx. 1.007812499
A ReduceInaccurate(8) yields 1/1.
*/
void Fraction::ReduceInaccurate( unsigned nSignificantBits )
{
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'ReduceInaccurate' on invalid fraction" );
return;
}
if ( !mnNumerator )
return;
auto a = toRational(mnNumerator, mnDenominator);
rational_ReduceInaccurate(a, nSignificantBits);
mnNumerator = a.numerator();
mnDenominator = a.denominator();
}
sal_Int32 Fraction::GetNumerator() const
{
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'GetNumerator()' on invalid fraction" );
return 0;
}
return mnNumerator;
}
sal_Int32 Fraction::GetDenominator() const
{
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'GetDenominator()' on invalid fraction" );
return -1;
}
return mnDenominator;
}
Fraction::operator sal_Int32() const
{
if ( !mbValid )
{
SAL_WARN( "tools.fraction", "'operator sal_Int32()' on invalid fraction" );
return 0;
}
return boost::rational_cast<sal_Int32>(toRational(mnNumerator, mnDenominator));
}
Fraction operator+( const Fraction& rVal1, const Fraction& rVal2 )
{
Fraction aErg( rVal1 );
aErg += rVal2;
return aErg;
}
Fraction operator-( const Fraction& rVal1, const Fraction& rVal2 )
{
Fraction aErg( rVal1 );
aErg -= rVal2;
return aErg;
}
Fraction operator*( const Fraction& rVal1, const Fraction& rVal2 )
{
Fraction aErg( rVal1 );
aErg *= rVal2;
return aErg;
}
Fraction operator/( const Fraction& rVal1, const Fraction& rVal2 )
{
Fraction aErg( rVal1 );
aErg /= rVal2;
return aErg;
}
bool operator !=( const Fraction& rVal1, const Fraction& rVal2 )
{
return !(rVal1 == rVal2);
}
bool operator <=( const Fraction& rVal1, const Fraction& rVal2 )
{
return !(rVal1 > rVal2);
}
bool operator >=( const Fraction& rVal1, const Fraction& rVal2 )
{
return !(rVal1 < rVal2);
}
bool operator == ( const Fraction& rVal1, const Fraction& rVal2 )
{
if ( !rVal1.mbValid || !rVal2.mbValid )
{
SAL_WARN( "tools.fraction", "'operator ==' with an invalid fraction" );
return false;
}
return toRational(rVal1.mnNumerator, rVal1.mnDenominator) == toRational(rVal2.mnNumerator, rVal2.mnDenominator);
}
bool operator < ( const Fraction& rVal1, const Fraction& rVal2 )
{
if ( !rVal1.mbValid || !rVal2.mbValid )
{
SAL_WARN( "tools.fraction", "'operator <' with an invalid fraction" );
return false;
}
return toRational(rVal1.mnNumerator, rVal1.mnDenominator) < toRational(rVal2.mnNumerator, rVal2.mnDenominator);
}
bool operator > ( const Fraction& rVal1, const Fraction& rVal2 )
{
if ( !rVal1.mbValid || !rVal2.mbValid )
{
SAL_WARN( "tools.fraction", "'operator >' with an invalid fraction" );
return false;
}
return toRational(rVal1.mnNumerator, rVal1.mnDenominator) > toRational(rVal2.mnNumerator, rVal2.mnDenominator);
}
// If dVal > LONG_MAX or dVal < LONG_MIN, the rational throws a boost::bad_rational.
// Otherwise, dVal and denominator are multiplied by 10, until one of them
// is larger than (LONG_MAX / 10).
//
// NOTE: here we use 'sal_Int32' due that only values in sal_Int32 range are valid.
static boost::rational<sal_Int32> rational_FromDouble(double dVal)
{
if ( dVal > std::numeric_limits<sal_Int32>::max() ||
dVal < std::numeric_limits<sal_Int32>::min() ||
std::isnan(dVal) )
throw boost::bad_rational();
const sal_Int32 nMAX = std::numeric_limits<sal_Int32>::max() / 10;
sal_Int32 nDen = 1;
while ( std::abs( dVal ) < nMAX && nDen < nMAX ) {
dVal *= 10;
nDen *= 10;
}
return boost::rational<sal_Int32>( sal_Int32(dVal), nDen );
}
/**
* Find the number of bits required to represent this number, using the CLZ intrinsic
*/
static int impl_NumberOfBits( sal_uInt32 nNum )
{
if (nNum == 0)
return 0;
#ifdef _MSC_VER
unsigned long r = 0;
_BitScanReverse(&r, nNum);
return r + 1;
#else
return 32 - __builtin_clz(nNum);
#endif
}
/** Inaccurate cancellation for a fraction.
Clip both nominator and denominator to said number of bits. If
either of those already have equal or less number of bits used,
this method does nothing.
@param nSignificantBits denotes, how many significant binary
digits to maintain, in both nominator and denominator.
@example ReduceInaccurate(8) has an error <1% [1/2^(8-1)] - the
largest error occurs with the following pair of values:
binary 1000000011111111111111111111111b/1000000000000000000000000000000b
= 1082130431/1073741824
= approx. 1.007812499
A ReduceInaccurate(8) yields 1/1.
*/
static void rational_ReduceInaccurate(boost::rational<sal_Int32>& rRational, unsigned nSignificantBits)
{
if ( !rRational )
return;
// http://www.boost.org/doc/libs/release/libs/rational/rational.html#Internal%20representation
sal_Int32 nMul = rRational.numerator();
if (nMul == std::numeric_limits<sal_Int32>::min())
{
// ofz#32973 Integer-overflow
return;
}
const bool bNeg = nMul < 0;
if (bNeg)
nMul = -nMul;
sal_Int32 nDiv = rRational.denominator();
DBG_ASSERT(nSignificantBits<65, "More than 64 bit of significance is overkill!");
// How much bits can we lose?
const int nMulBitsToLose = std::max( ( impl_NumberOfBits( nMul ) - int( nSignificantBits ) ), 0 );
const int nDivBitsToLose = std::max( ( impl_NumberOfBits( nDiv ) - int( nSignificantBits ) ), 0 );
const int nToLose = std::min( nMulBitsToLose, nDivBitsToLose );
// Remove the bits
nMul >>= nToLose;
nDiv >>= nToLose;
if ( !nMul || !nDiv ) {
// Return without reduction
OSL_FAIL( "Oops, we reduced too much..." );
return;
}
rRational.assign( bNeg ? -nMul : nMul, nDiv );
}
size_t Fraction::GetHashValue() const
{
size_t hash = 0;
o3tl::hash_combine( hash, mnNumerator );
o3tl::hash_combine( hash, mnDenominator );
o3tl::hash_combine( hash, mbValid );
return hash;
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */