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authorrubidium <rubidium@openttd.org>2007-01-02 19:19:48 +0000
committerrubidium <rubidium@openttd.org>2007-01-02 19:19:48 +0000
commit66bbf336c6af7353ef0aeed58002c46543b30635 (patch)
treead4a63860df2626b22f77e7dac712e958bea54cb /src/date.h
parentccc0a3f4dbf58c005b22341ac8874252924690cd (diff)
downloadopenttd-66bbf336c6af7353ef0aeed58002c46543b30635.tar.xz
(svn r7759) -Merge: makefile rewrite. This merge features:
- A proper ./configure, so everything needs to be configured only once, not for every make. - Usage of makedepend when available. This greatly reduces the time needed for generating the dependencies. - A generator for all project files. There is a single file with sources, which is used to generate Makefiles and the project files for MSVC. - Proper support for OSX universal binaries. - Object files for non-MSVC compiles are also placed in separate directories, making is faster to switch between debug and release compiles and it does not touch the directory with the source files. - Functionality to make a bundle of all needed files for for example a nightly or distribution of a binary with all needed GRFs and language files. Note: as this merge moves almost all files, it is recommended to make a backup of your working copy before updating your working copy.
Diffstat (limited to 'src/date.h')
-rw-r--r--src/date.h61
1 files changed, 61 insertions, 0 deletions
diff --git a/src/date.h b/src/date.h
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+++ b/src/date.h
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+/* $Id$ */
+
+#ifndef DATE_H
+#define DATE_H
+
+#include "openttd.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 */