(svn r7687) [cbh] - Fix: trains can now enter the bridge from side. They still can't leave it from side (pathfinder will need to be invoked when the other ramp is entered). Also the code is not very clear and needs review. It is more proof of concept than final solution. I hope that somebody smarter (Celestar) can do it better.
/* $Id$ */
#ifndef DATE_H
#define DATE_H
/**
* 1 day is 74 ticks; _date_fract used to be uint16 and incremented by 885. On
* an overflow the new day begun and 65535 / 885 = 74.
* 1 tick is approximately 30 ms.
* 1 day is thus about 2 seconds (74 * 30 = 2220) on a machine that can run OpenTTD normally
*/
#define DAY_TICKS 74
/*
* ORIGINAL_BASE_YEAR, ORIGINAL_MAX_YEAR and DAYS_TILL_ORIGINAL_BASE_YEAR are
* primarily used for loading newgrf and savegame data and returning some
* newgrf (callback) functions that were in the original (TTD) inherited
* format, where '_date == 0' meant that it was 1920-01-01.
*/
/** The minimum starting year/base year of the original TTD */
#define ORIGINAL_BASE_YEAR 1920
/** The maximum year of the original TTD */
#define ORIGINAL_MAX_YEAR 2090
/**
* The offset in days from the '_date == 0' till
* 'ConvertYMDToDate(ORIGINAL_BASE_YEAR, 0, 1)'
*/
#define DAYS_TILL_ORIGINAL_BASE_YEAR (365 * ORIGINAL_BASE_YEAR + ORIGINAL_BASE_YEAR / 4 - ORIGINAL_BASE_YEAR / 100 + ORIGINAL_BASE_YEAR / 400)
/* The absolute minimum & maximum years in OTTD */
#define MIN_YEAR 0
/* MAX_YEAR, nicely rounded value of the number of years that can
* be encoded in a single 32 bits date, about 2^31 / 366 years. */
#define MAX_YEAR 5000000
/* Year and Date are defined elsewhere */
typedef uint8 Month;
typedef uint8 Day;
typedef uint16 DateFract;
typedef struct YearMonthDay {
Year year;
Month month;
Day day;
} YearMonthDay;
extern Year _cur_year;
extern Month _cur_month;
extern Date _date;
extern DateFract _date_fract;
void SetDate(Date date);
void ConvertDateToYMD(Date date, YearMonthDay *ymd);
Date ConvertYMDToDate(Year year, Month month, Day day);
#endif /* DATE_H */