File indexing completed on 2024-04-21 03:42:13

 /*
     SPDX-FileCopyrightText: 2016 Akarsh Simha <akarsh.simha@kdemail.net>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #pragma once
 
 #include "dms.h"
 
 /**
  * @class CachingDms
  * @short a dms subclass that caches its sine and cosine values every time the angle is changed.
  * @note This is to be used for those angles where sin/cos is repeatedly computed.
  * @author Akarsh Simha <akarsh@kde.org>
  */
 
 class CachingDms : public dms
 {
   public:
     /**
      * @short Default Constructor
      */
     CachingDms() : dms(), m_sin(NaN::d), m_cos(NaN::d)
     {
 #ifdef COUNT_DMS_SINCOS_CALLS
         m_cacheUsed = true;
         ++cachingdms_constructor_calls;
 #endif
     };
 
     /**
      * @short Degree angle constructor
      * @param x is the angle in degrees
      */
     explicit CachingDms(const double &x);
 
     /**
      * @short QString constructor
      */
     explicit CachingDms(const QString &s, bool isDeg = true);
 
     /**
      * @short DMS representation constructor
      */
     explicit CachingDms(const int &d, const int &m = 0, const int &s = 0, const int &ms = 0);
 
 #ifdef COUNT_DMS_SINCOS_CALLS
     /**
      * @short Destructor must count bad cache uses
      */
     ~CachingDms();
 #endif
 
     /**
      * @short Sets the angle in degrees supplied as a double
      * @note Re-implements dms::setD() with sine/cosine caching
      */
     inline void setD(const double &x) override
     {
         dms::setD(x);
         dms::SinCos(m_sin, m_cos);
 #ifdef COUNT_DMS_SINCOS_CALLS
         cachingdms_delta -= 2;
         if (!m_cacheUsed)
             ++cachingdms_bad_uses;
         m_cacheUsed = false;
 #endif
     }
 
     /**
      * @short Overrides dms::setD()
      */
     inline void setD(const int &d, const int &m, const int &s, const int &ms = 0) override
     {
         dms::setD(d, m, s, ms);
         dms::SinCos(m_sin, m_cos);
 #ifdef COUNT_DMS_SINCOS_CALLS
         cachingdms_delta -= 2;
         if (!m_cacheUsed)
             ++cachingdms_bad_uses;
         m_cacheUsed = false;
 #endif
     }
 
     /**
      * @short Sets the angle in hours, supplied as a double
      * @note Re-implements dms::setH() with sine/cosine caching
      * @note While this and other methods internally call setD, we want to avoid unnecessary vtable lookups. We'd rather have inline than virtual when speed matters in general.
      */
     inline void setH(const double &x) override
     {
         dms::setH(x);
         dms::SinCos(m_sin, m_cos);
 #ifdef COUNT_DMS_SINCOS_CALLS
         cachingdms_delta -= 2;
         if (!m_cacheUsed)
             ++cachingdms_bad_uses;
         m_cacheUsed = false;
 #endif
     }
 
     /**
      * @short Sets the angle in HMS form
      * @note Re-implements dms::setH() with sine/cosine caching
      */
     inline void setH(const int &h, const int &m, const int &s, const int &ms = 0) override
     {
         dms::setH(h, m, s, ms);
         dms::SinCos(m_sin, m_cos);
 #ifdef COUNT_DMS_SINCOS_CALLS
         cachingdms_delta -= 2;
 #endif
     }
 
     /**
      * @short Sets the angle from string
      * @note Re-implements dms::setFromString()
      */
     inline bool setFromString(const QString &s, bool isDeg = true) override
     {
         bool retval = dms::setFromString(s, isDeg);
         dms::SinCos(m_sin, m_cos);
 #ifdef COUNT_DMS_SINCOS_CALLS
         cachingdms_delta -= 2;
         if (!m_cacheUsed)
             ++cachingdms_bad_uses;
         m_cacheUsed = false;
 #endif
         return retval;
     }
 
     /**
      * @short Sets the angle in radians
      */
     inline void setRadians(const double &a) override
     {
         dms::setRadians(a);
         dms::SinCos(m_sin, m_cos);
 #ifdef COUNT_DMS_SINCOS_CALLS
         cachingdms_delta -= 2;
         if (!m_cacheUsed)
             ++cachingdms_bad_uses;
         m_cacheUsed = false;
 #endif
     }
 
     /**
      * @short Sets the angle using atan2()
      * @note The advantage is that we can calculate sin/cos faster because we know the tangent
      */
     void setUsing_atan2(const double &y, const double &x);
 
     /**
      * @short Sets the angle using asin()
      * @param sine Sine of the angle
      * @note The advantage is that we can cache the sine value supplied
      * @note The limited range of asin must be borne in mind
      */
     void setUsing_asin(const double &sine);
 
     /**
      * @short Sets the angle using acos()
      * @param cosine Cosine of the angle
      * @note The advantage is that we can cache the cosine value supplied
      * @note The limited range of acos must be borne in mind
      */
     void setUsing_acos(const double &cosine);
 
     /**
      * @short Get the sine and cosine together
      * @note Re-implements dms::SinCos()
      * @note This just uses the cached values assuming that they are good
      */
     inline void SinCos(double &s, double &c) const
     {
         s = m_sin;
         c = m_cos;
 #ifdef COUNT_DMS_SINCOS_CALLS
         cachingdms_delta += 2;
         m_cacheUsed = true;
 #endif
     }
 
     /**
      * @short Get the sine of this angle
      * @note Re-implements dms::sin()
      * @note This just uses the cached value assuming that it is good
      */
     inline double sin() const
     {
 #ifdef COUNT_DMS_SINCOS_CALLS
         ++cachingdms_delta;
         m_cacheUsed = true;
 #endif
         return m_sin;
     }
 
     /**
      * @short Get the cosine of this angle
      * @note Re-implements dms::cos()
      * @note This just uses the cached value assuming that it is good
      */
     inline double cos() const
     {
 #ifdef COUNT_DMS_SINCOS_CALLS
         ++cachingdms_delta;
         m_cacheUsed = true;
 #endif
         return m_cos;
     }
 
     /**
      * @short Construct an angle from the given string
      * @note Re-implements dms::fromString()
      */
     static CachingDms fromString(const QString &s, bool deg);
 
     /**
      * @short operator -
      * @note In addition to negating the angle, we negate the sine value
      */
     CachingDms operator-();
 
     /**
      * @short Casting constructor
      */
     CachingDms(const dms &angle);
 
 #ifdef COUNT_DMS_SINCOS_CALLS
     /**
      * Copy constructor that sets m_cacheUsed to true
      */
     CachingDms(const CachingDms &o);
     CachingDms &operator=(const CachingDms &o);
 #endif
 
   private:
     double m_sin, m_cos; // Cached values
 
     /**
      * @short Private constructor used to create a CachingDms with known sine and cosine
      */
     explicit CachingDms(const double &degrees, const double &sine, const double &cosine)
         : dms(degrees), m_sin(sine), m_cos(cosine)
     {
 #ifdef COUNT_DMS_SINCOS_CALLS
         ++cachingdms_constructor_calls;
         m_cacheUsed = false;
 #endif
     }
 
     /**
      * @short Addition and subtraction operators
      * @note Uses trigonometric identities to find the new trigonometric values
      * @note Avoid repeated use, as the round-off errors will accumulate!
      */
     friend CachingDms operator+(const CachingDms &, const CachingDms &);
     friend CachingDms operator-(const CachingDms &, const CachingDms &);
     friend CachingDms operator+(const dms &a, const CachingDms &b);
     friend CachingDms operator-(const dms &a, const CachingDms &b);
     friend CachingDms operator+(const CachingDms &a, const dms &b);
     friend CachingDms operator-(const CachingDms &a, const dms &b);
 
 #ifdef COUNT_DMS_SINCOS_CALLS
   private:
     mutable bool m_cacheUsed;
 
   public:
     static unsigned long cachingdms_constructor_calls;
     static long cachingdms_delta; // difference of ( trig function calls ) - ( trig computations )
     static unsigned long cachingdms_bad_uses;
 #endif
 };