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Diffstat (limited to 'include/basegfx/numeric/ftools.hxx')
| -rw-r--r-- | include/basegfx/numeric/ftools.hxx | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/include/basegfx/numeric/ftools.hxx b/include/basegfx/numeric/ftools.hxx new file mode 100644 index 000000000..78f4eb1e7 --- /dev/null +++ b/include/basegfx/numeric/ftools.hxx @@ -0,0 +1,235 @@ +/* -*- 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 . + */ + +#pragma once + +#include <rtl/math.h> +#include <cmath> +#include <math.h> +#include <basegfx/basegfxdllapi.h> +#include <limits> +#include <algorithm> + +// standard PI defines from solar.h, but we do not want to link against tools + +#ifndef F_PI +#define F_PI M_PI +#endif +#ifndef F_PI2 +#define F_PI2 M_PI_2 +#endif +#ifndef F_PI4 +#define F_PI4 M_PI_4 +#endif +#ifndef F_PI180 +#define F_PI180 (M_PI/180.0) +#endif +#ifndef F_PI1800 +#define F_PI1800 (M_PI/1800.0) +#endif +#ifndef F_PI18000 +#define F_PI18000 (M_PI/18000.0) +#endif +#ifndef F_2PI +#define F_2PI (2.0*M_PI) +#endif + + +// fTools defines + +namespace basegfx +{ + /** Round double to nearest integer + + @return the nearest integer + */ + inline sal_Int32 fround( double fVal ) + { + if (fVal >= std::numeric_limits<sal_Int32>::max() - .5) + return std::numeric_limits<sal_Int32>::max(); + else if (fVal <= std::numeric_limits<sal_Int32>::min() + .5) + return std::numeric_limits<sal_Int32>::min(); + return fVal > 0.0 ? static_cast<sal_Int32>( fVal + .5 ) : static_cast<sal_Int32>( fVal - .5 ); + } + + /** Round double to nearest integer + + @return the nearest 64 bit integer + */ + inline sal_Int64 fround64( double fVal ) + { + return fVal > 0.0 ? static_cast<sal_Int64>( fVal + .5 ) : -static_cast<sal_Int64>( -fVal + .5 ); + } + + /** Prune a small epsilon range around zero. + + Use this method e.g. for calculating scale values. There, it + is usually advisable not to set a scaling to 0.0, because that + yields singular transformation matrices. + + @param fVal + An arbitrary, but finite and valid number + + @return either fVal, or a small value slightly above (when + fVal>0) or below (when fVal<0) zero. + */ + inline double pruneScaleValue( double fVal ) + { + // old version used ::std::min/max, but this collides if min is defined as preprocessor + // macro which is the case e.g with windows.h headers. The simplest way to avoid this is to + // just use the full comparison. I keep the original here, maybe there will be a better + // solution some day. + + //return fVal < 0.0 ? + // (::std::min(fVal,-0.00001)) : + // (::std::max(fVal,0.00001)); + + if(fVal < 0.0) + return std::min(fVal, -0.00001); + else + return std::max(fVal, 0.00001); + } + + /** Convert value from degrees to radians + */ + constexpr double deg2rad( double v ) + { + // divide first, to get exact values for v being a multiple of + // 90 degrees + return v / 90.0 * M_PI_2; + } + + /** Convert value radians to degrees + */ + constexpr double rad2deg( double v ) + { + // divide first, to get exact values for v being a multiple of + // pi/2 + return v / M_PI_2 * 90.0; + } + + /** Snap v to nearest multiple of fStep, from negative and + positive side. + + Examples: + + snapToNearestMultiple(-0.1, 0.5) = 0.0 + snapToNearestMultiple(0.1, 0.5) = 0.0 + snapToNearestMultiple(0.25, 0.5) = 0.0 + snapToNearestMultiple(0.26, 0.5) = 0.5 + */ + BASEGFX_DLLPUBLIC double snapToNearestMultiple(double v, const double fStep); + + /** Snap v to the range [0.0 .. fWidth] using modulo + */ + double snapToZeroRange(double v, double fWidth); + + /** Snap v to the range [fLow .. fHigh] using modulo + */ + double snapToRange(double v, double fLow, double fHigh); + + /** return fValue with the sign of fSignCarrier, thus evtl. changed + */ + inline double copySign(double fValue, double fSignCarrier) + { +#ifdef _WIN32 + return _copysign(fValue, fSignCarrier); +#else + return copysign(fValue, fSignCarrier); +#endif + } + + /** RotateFlyFrame3: Normalize to range defined by [0.0 ... fRange[, independent + if v is positive or negative. + + Examples: + + normalizeToRange(0.5, -1.0) = 0.0 + normalizeToRange(0.5, 0.0) = 0.0 + normalizeToRange(0.5, 1.0) = 0.5 + normalizeToRange(-0.5, 1.0) = 0.5 + normalizeToRange(-0.3, 1.0) = 0.7 + normalizeToRange(-0.7, 1.0) = 0.3 + normalizeToRange(3.5, 1.0) = 0.5 + normalizeToRange(3.3, 1.0) = 0.3 + normalizeToRange(3.7, 1.0) = 0.7 + normalizeToRange(-3.5, 1.0) = 0.5 + normalizeToRange(-3.3, 1.0) = 0.7 + normalizeToRange(-3.7, 1.0) = 0.3 + */ + BASEGFX_DLLPUBLIC double normalizeToRange(double v, const double fRange); + + class BASEGFX_DLLPUBLIC fTools + { + public: + /// Get threshold value for equalZero and friends + static double getSmallValue() { return 0.000000001f; } + + /// Compare against small value + static bool equalZero(const double& rfVal) + { + return (fabs(rfVal) <= getSmallValue()); + } + + /// Compare against given small value + static bool equalZero(const double& rfVal, const double& rfSmallValue) + { + return (fabs(rfVal) <= rfSmallValue); + } + + static bool equal(const double& rfValA, const double& rfValB) + { + // changed to approxEqual usage for better numerical correctness + return rtl_math_approxEqual(rfValA, rfValB); + } + + static bool equal(const double& rfValA, const double& rfValB, const double& rfSmallValue) + { + return (fabs(rfValA - rfValB) <= rfSmallValue); + } + + static bool less(const double& rfValA, const double& rfValB) + { + return (rfValA < rfValB && !equal(rfValA, rfValB)); + } + + static bool lessOrEqual(const double& rfValA, const double& rfValB) + { + return (rfValA < rfValB || equal(rfValA, rfValB)); + } + + static bool more(const double& rfValA, const double& rfValB) + { + return (rfValA > rfValB && !equal(rfValA, rfValB)); + } + + static bool moreOrEqual(const double& rfValA, const double& rfValB) + { + return (rfValA > rfValB || equal(rfValA, rfValB)); + } + + static bool betweenOrEqualEither(const double& rfValA, const double& rfValB, const double& rfValC) + { + return (rfValA > rfValB && rfValA < rfValC) || equal(rfValA, rfValB) || equal(rfValA, rfValC); + } + + }; +} // end of namespace basegfx + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |