src/timer/timer_game_common.cpp

   1 /*
   2  * This file is part of OpenTTD.
   3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /**
   9  * @file timer_game_common.cpp
  10  * This file implements the common timer logic for the game-calendar timers.
  11  */
  12
  13 #include "../stdafx.h"
  14
  15 #include "timer_game_common.h"
  16 #include "timer_game_calendar.h"
  17 #include "timer_game_economy.h"
  18
  19 #include "../safeguards.h"
  20
  21 #define M(a, b) ((a << 5) | b)
  22 static constexpr uint16_t _month_date_from_year_day[] = {
  23         M(0, 1), M(0, 2), M(0, 3), M(0, 4), M(0, 5), M(0, 6), M(0, 7), M(0, 8), M(0, 9), M(0, 10), M(0, 11), M(0, 12), M(0, 13), M(0, 14), M(0, 15), M(0, 16), M(0, 17), M(0, 18), M(0, 19), M(0, 20), M(0, 21), M(0, 22), M(0, 23), M(0, 24), M(0, 25), M(0, 26), M(0, 27), M(0, 28), M(0, 29), M(0, 30), M(0, 31),
  24         M(1, 1), M(1, 2), M(1, 3), M(1, 4), M(1, 5), M(1, 6), M(1, 7), M(1, 8), M(1, 9), M(1, 10), M(1, 11), M(1, 12), M(1, 13), M(1, 14), M(1, 15), M(1, 16), M(1, 17), M(1, 18), M(1, 19), M(1, 20), M(1, 21), M(1, 22), M(1, 23), M(1, 24), M(1, 25), M(1, 26), M(1, 27), M(1, 28), M(1, 29),
  25         M(2, 1), M(2, 2), M(2, 3), M(2, 4), M(2, 5), M(2, 6), M(2, 7), M(2, 8), M(2, 9), M(2, 10), M(2, 11), M(2, 12), M(2, 13), M(2, 14), M(2, 15), M(2, 16), M(2, 17), M(2, 18), M(2, 19), M(2, 20), M(2, 21), M(2, 22), M(2, 23), M(2, 24), M(2, 25), M(2, 26), M(2, 27), M(2, 28), M(2, 29), M(2, 30), M(2, 31),
  26         M(3, 1), M(3, 2), M(3, 3), M(3, 4), M(3, 5), M(3, 6), M(3, 7), M(3, 8), M(3, 9), M(3, 10), M(3, 11), M(3, 12), M(3, 13), M(3, 14), M(3, 15), M(3, 16), M(3, 17), M(3, 18), M(3, 19), M(3, 20), M(3, 21), M(3, 22), M(3, 23), M(3, 24), M(3, 25), M(3, 26), M(3, 27), M(3, 28), M(3, 29), M(3, 30),
  27         M(4, 1), M(4, 2), M(4, 3), M(4, 4), M(4, 5), M(4, 6), M(4, 7), M(4, 8), M(4, 9), M(4, 10), M(4, 11), M(4, 12), M(4, 13), M(4, 14), M(4, 15), M(4, 16), M(4, 17), M(4, 18), M(4, 19), M(4, 20), M(4, 21), M(4, 22), M(4, 23), M(4, 24), M(4, 25), M(4, 26), M(4, 27), M(4, 28), M(4, 29), M(4, 30), M(4, 31),
  28         M(5, 1), M(5, 2), M(5, 3), M(5, 4), M(5, 5), M(5, 6), M(5, 7), M(5, 8), M(5, 9), M(5, 10), M(5, 11), M(5, 12), M(5, 13), M(5, 14), M(5, 15), M(5, 16), M(5, 17), M(5, 18), M(5, 19), M(5, 20), M(5, 21), M(5, 22), M(5, 23), M(5, 24), M(5, 25), M(5, 26), M(5, 27), M(5, 28), M(5, 29), M(5, 30),
  29         M(6, 1), M(6, 2), M(6, 3), M(6, 4), M(6, 5), M(6, 6), M(6, 7), M(6, 8), M(6, 9), M(6, 10), M(6, 11), M(6, 12), M(6, 13), M(6, 14), M(6, 15), M(6, 16), M(6, 17), M(6, 18), M(6, 19), M(6, 20), M(6, 21), M(6, 22), M(6, 23), M(6, 24), M(6, 25), M(6, 26), M(6, 27), M(6, 28), M(6, 29), M(6, 30), M(6, 31),
  30         M(7, 1), M(7, 2), M(7, 3), M(7, 4), M(7, 5), M(7, 6), M(7, 7), M(7, 8), M(7, 9), M(7, 10), M(7, 11), M(7, 12), M(7, 13), M(7, 14), M(7, 15), M(7, 16), M(7, 17), M(7, 18), M(7, 19), M(7, 20), M(7, 21), M(7, 22), M(7, 23), M(7, 24), M(7, 25), M(7, 26), M(7, 27), M(7, 28), M(7, 29), M(7, 30), M(7, 31),
  31         M(8, 1), M(8, 2), M(8, 3), M(8, 4), M(8, 5), M(8, 6), M(8, 7), M(8, 8), M(8, 9), M(8, 10), M(8, 11), M(8, 12), M(8, 13), M(8, 14), M(8, 15), M(8, 16), M(8, 17), M(8, 18), M(8, 19), M(8, 20), M(8, 21), M(8, 22), M(8, 23), M(8, 24), M(8, 25), M(8, 26), M(8, 27), M(8, 28), M(8, 29), M(8, 30),
  32         M(9, 1), M(9, 2), M(9, 3), M(9, 4), M(9, 5), M(9, 6), M(9, 7), M(9, 8), M(9, 9), M(9, 10), M(9, 11), M(9, 12), M(9, 13), M(9, 14), M(9, 15), M(9, 16), M(9, 17), M(9, 18), M(9, 19), M(9, 20), M(9, 21), M(9, 22), M(9, 23), M(9, 24), M(9, 25), M(9, 26), M(9, 27), M(9, 28), M(9, 29), M(9, 30), M(9, 31),
  33         M(10, 1), M(10, 2), M(10, 3), M(10, 4), M(10, 5), M(10, 6), M(10, 7), M(10, 8), M(10, 9), M(10, 10), M(10, 11), M(10, 12), M(10, 13), M(10, 14), M(10, 15), M(10, 16), M(10, 17), M(10, 18), M(10, 19), M(10, 20), M(10, 21), M(10, 22), M(10, 23), M(10, 24), M(10, 25), M(10, 26), M(10, 27), M(10, 28), M(10, 29), M(10, 30),
  34         M(11, 1), M(11, 2), M(11, 3), M(11, 4), M(11, 5), M(11, 6), M(11, 7), M(11, 8), M(11, 9), M(11, 10), M(11, 11), M(11, 12), M(11, 13), M(11, 14), M(11, 15), M(11, 16), M(11, 17), M(11, 18), M(11, 19), M(11, 20), M(11, 21), M(11, 22), M(11, 23), M(11, 24), M(11, 25), M(11, 26), M(11, 27), M(11, 28), M(11, 29), M(11, 30), M(11, 31),
  35 };
  36 #undef M
  37
  38 static constexpr uint16_t ACCUM_JAN = 0;
  39 static constexpr uint16_t ACCUM_FEB = ACCUM_JAN + 31;
  40 static constexpr uint16_t ACCUM_MAR = ACCUM_FEB + 29;
  41 static constexpr uint16_t ACCUM_APR = ACCUM_MAR + 31;
  42 static constexpr uint16_t ACCUM_MAY = ACCUM_APR + 30;
  43 static constexpr uint16_t ACCUM_JUN = ACCUM_MAY + 31;
  44 static constexpr uint16_t ACCUM_JUL = ACCUM_JUN + 30;
  45 static constexpr uint16_t ACCUM_AUG = ACCUM_JUL + 31;
  46 static constexpr uint16_t ACCUM_SEP = ACCUM_AUG + 31;
  47 static constexpr uint16_t ACCUM_OCT = ACCUM_SEP + 30;
  48 static constexpr uint16_t ACCUM_NOV = ACCUM_OCT + 31;
  49 static constexpr uint16_t ACCUM_DEC = ACCUM_NOV + 30;
  50
  51 /** Number of days to pass from the first day in the year before reaching the first of a month. */
  52 static constexpr uint16_t _accum_days_for_month[] = {
  53         ACCUM_JAN, ACCUM_FEB, ACCUM_MAR, ACCUM_APR,
  54         ACCUM_MAY, ACCUM_JUN, ACCUM_JUL, ACCUM_AUG,
  55         ACCUM_SEP, ACCUM_OCT, ACCUM_NOV, ACCUM_DEC,
  56 };
  57
  58 /**
  59  * Converts a Date to a Year, Month & Day.
  60  * @param date the date to convert from
  61  * @returns YearMonthDay representation of the Date.
  62  */
  63 template <class T>
  64 /* static */ typename TimerGame<T>::YearMonthDay TimerGame<T>::CalendarConvertDateToYMD(Date date)
  65 {
  66         /* Year determination in multiple steps to account for leap
  67          * years. First do the large steps, then the smaller ones.
  68          */
  69
  70         /* There are 97 leap years in 400 years */
  71         Year yr = 400 * (date.base() / (TimerGameConst<T>::DAYS_IN_YEAR * 400 + 97));
  72         int rem = date.base() % (TimerGameConst<T>::DAYS_IN_YEAR * 400 + 97);
  73
  74         if (rem >= TimerGameConst<T>::DAYS_IN_YEAR * 100 + 25) {
  75                 /* There are 25 leap years in the first 100 years after
  76                  * every 400th year, as every 400th year is a leap year */
  77                 yr += 100;
  78                 rem -= TimerGameConst<T>::DAYS_IN_YEAR * 100 + 25;
  79
  80                 /* There are 24 leap years in the next couple of 100 years */
  81                 yr += 100 * (rem / (TimerGameConst<T>::DAYS_IN_YEAR * 100 + 24));
  82                 rem = (rem % (TimerGameConst<T>::DAYS_IN_YEAR * 100 + 24));
  83         }
  84
  85         if (!IsLeapYear(yr) && rem >= TimerGameConst<T>::DAYS_IN_YEAR * 4) {
  86                 /* The first 4 year of the century are not always a leap year */
  87                 yr += 4;
  88                 rem -= TimerGameConst<T>::DAYS_IN_YEAR * 4;
  89         }
  90
  91         /* There is 1 leap year every 4 years */
  92         yr += 4 * (rem / (TimerGameConst<T>::DAYS_IN_YEAR * 4 + 1));
  93         rem = rem % (TimerGameConst<T>::DAYS_IN_YEAR * 4 + 1);
  94
  95         /* The last (max 3) years to account for; the first one
  96          * can be, but is not necessarily a leap year */
  97         while (rem >= (IsLeapYear(yr) ? TimerGameConst<T>::DAYS_IN_LEAP_YEAR : TimerGameConst<T>::DAYS_IN_YEAR)) {
  98                 rem -= IsLeapYear(yr) ? TimerGameConst<T>::DAYS_IN_LEAP_YEAR : TimerGameConst<T>::DAYS_IN_YEAR;
  99                 yr++;
 100         }
 101
 102         /* Skip the 29th of February in non-leap years */
 103         if (!IsLeapYear(yr) && rem >= ACCUM_MAR - 1) rem++;
 104
 105         uint16_t x = _month_date_from_year_day[rem];
 106
 107         YearMonthDay ymd;
 108         ymd.year = yr;
 109         ymd.month = x >> 5;
 110         ymd.day = x & 0x1F;
 111         return ymd;
 112 }
 113
 114 /**
 115  * Converts a tuple of Year, Month and Day to a Date.
 116  * @param year  is a number between 0..MAX_YEAR
 117  * @param month is a number between 0..11
 118  * @param day   is a number between 1..31
 119  * @returns The equivalent date.
 120  */
 121 template <class T>
 122 /* static */ typename TimerGame<T>::Date TimerGame<T>::CalendarConvertYMDToDate(Year year, Month month, Day day)
 123 {
 124         /* Day-offset in a leap year */
 125         int days = _accum_days_for_month[month] + day - 1;
 126
 127         /* Account for the missing of the 29th of February in non-leap years */
 128         if (!IsLeapYear(year) && days >= ACCUM_MAR) days--;
 129
 130         return DateAtStartOfYear(year) + days;
 131 }
 132
 133 /* Create instances of the two template variants that we have.
 134  * This is needed, as this templated functions are not in a header-file. */
 135 template TimerGame<struct Calendar>::YearMonthDay TimerGame<struct Calendar>::CalendarConvertDateToYMD(Date date);
 136 template TimerGame<struct Economy>::YearMonthDay TimerGame<struct Economy>::CalendarConvertDateToYMD(Date date);
 137
 138 template TimerGame<struct Calendar>::Date TimerGame<struct Calendar>::CalendarConvertYMDToDate(Year year, Month month, Day day);
 139 template TimerGame<struct Economy>::Date TimerGame<struct Economy>::CalendarConvertYMDToDate(Year year, Month month, Day day);