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 *   Licensed to the Apache Software Foundation (ASF) under one or more
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#ifndef INCLUDED_BASEGFX_NUMERIC_FTOOLS_HXX
#define INCLUDED_BASEGFX_NUMERIC_FTOOLS_HXX

#include <rtl/math.hxx>
#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 WNT
        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

#endif // INCLUDED_BASEGFX_NUMERIC_FTOOLS_HXX

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