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+//===== rAthena Documentation ================================
+//= rAthena Map Cache Builder and Format Documentation
+//===== By: ==================================================
+//= DracoRPG
+//===== Current Version: =====================================
+//= 20070724
+//===== Description: =========================================
+//= A complete manual for rAthena's map cache generator as 
+//= well as a reference on the map cache format used.
+//============================================================
+
+Preface:
+-------------------------------------------------------------------------------
+
+Since SVN revision ~10000, the map-server no longer knows how to read GRFs directly. It reads maps from a
+"map cache" file that contains all and only the useful data about the maps. A map cache containing every official
+kRO Sakray map currently supported by rAthena is provided as a default.
+If you have custom maps or want to minimize the size of your map cache because your server does not load all of them
+(multi-map-server or light test server), you can use the map cache builder to generate a new one fitting your needs.
+
+Map cache builder manual:
+-------------------------------------------------------------------------------
+
+The source code for the map cache builder is located in src/tool/. It can be built using "make tools" if you use the Makefile
+or using the "mapcache" project under Visual Studio. Named "mapcache", the executable will be in your rAthena main folder.
+The map cache builder needs 3 file paths : one is a list of GRFs and/or data directory containing the maps, the second
+is the list of maps to add to the map cache, and the last one is the path of the map cache to generate. Default values for
+those paths are "tools/mapcache/grf_files.txt", "db/map_index.txt" and "db/(pre-)re/map_cache.dat".
+
+As of r16867, the mapcache within SVN can be located in db/pre-re/ and db/re/. This is due to renewal and pre-renewal modes
+having slightly different maps. When building your cache, you should ensure you're pointing the tool to the correct location.
+
+The list of GRFs and/or data directory must follow the format and indication of the default file: as many "grf:" entries as
+you wish and optionally only one "data_dir:" entry with trailing backslash included. // comments are supported as usual.
+In fact, any file with one map name per line can be used as a map list, that's why the map index list is used as a default:
+we are sure it contains every map supported by the server. Anything after the map name is ignored, // comments are supported
+and if the first word on the line is "map:" then the second word is used as the map name instead: that allows using
+maps_athena.conf as your map list, which is handy if you want to generate a minimal map cache for each of your multiple
+map-servers.
+The map cache file path can point to an already existing file, as the builder adds a map only if it's not already cached.
+This way, you can add custom maps to the base map cache without even needing kRO Sakray maps. If you wish to rebuild the
+entire map cache, though, you can either provide a path to a non-existing file, or force the rebuild mode.
+
+Here are the command-line arguments you can provide to the map cache builder to customize its behavior:
+ -grf path/to/grf/list
+   Allows to specify the file containing the list of GRFs and/or data directory
+ -list path/to/map/list
+   Allows to specify the file containing the list of maps to add to the map cache
+ -cache path/to/map/cache
+   Allows to specify the path to the generated map cache
+ -rebuild
+   Allows to force the rebuild mode (map cache will be overwritten even if it already exists)
+
+
+Map cache format reference:
+-------------------------------------------------------------------------------
+
+The file is written as little-endian, even on big-endian systems, for cross-compatibility reasons. Appropriate conversions
+are done when generating it, so don't worry about it.
+The first 6 bytes are a main header:
+<unsigned int> file size
+<unsigned short> number of maps
+Then maps are stored one right after another:
+<12-characters-long string> map name
+<short> X size
+<short> Y size
+<long> compressed cell data length
+<variable> compressed cell data