The code of VCMI is divided into several main parts: client, server, lib and AIs, each one in a separate binary file. # The big picture
Architektura.png
VCMI contains three core projects: VCMI_lib (dll / so), VCMI_client (executable) and VCMI_server (executable). [Server](Server "wikilink") handles all [game mechanics](game_mechanics "wikilink") and events. [Client](Client "wikilink") presents [game state](game_state "wikilink") and events to player and collects input from him. During the game, we have one (and only one) server and one or more (one for each player computer) clients. Important: State of the game and its mechanics are synchronized between clients and server. All changes to the game state or mechanics must be done by server which will send appropriate notices to clients. ## Game state It's basically CGameState class object and everything that's accessible from it: map (with objects), player statuses, game options, etc. ## Bonus system One of the more important pieces of VCMI is the [bonus system](bonus_system "wikilink"). It's described in a separate article. ## Configuration Most of VCMI configuration files uses Json format and located in "config" directory ### [Json parser and writer](Json_parser_and_writer "wikilink") # Client ## Main purposes of client [Client](Client "wikilink") is responsible for: - displaying state of game to human player - capturing player's actions and sending requests to server - displaying changes in state of game indicated by server ## Rendering of graphics Rendering of graphics relies heavily on SDL. Currently we do not have any wrapper for SDL internal structures and most of rendering is about blitting surfaces using SDL_BlitSurface. We have a few function that make rendering easier or make specific parts of rendering (like printing text). They are places in client/SDL_Extensions and client/SDL_Framerate (the second one contains code responsible for keeping appropriate framerate, it should work more smart than just SDL_Delay(miliseconds)). In rendering, Interface object system is quite helpful. Its base is CIntObject class that is basically a base class for our library of GUI components and other objects. ### Video player Located in client/VideoHandler.cpp/.h, have several platform-specific versions: - For 32-bit Windows - using original 32-bit libraries (binkw32.dll, smackw32.dll) - For \*nix systems - using ffmpeg libraries. - Empty player for 64-bit Windows ### [Primitive controls](Primitive_controls "wikilink") ## [Adventure map interface](Adventure_map_interface "wikilink") TBD ## [Town interface](Town_interface "wikilink") TBD ## [Battle interface](Battle_interface "wikilink") # Server ## Main purposes of server [Server](Server "wikilink") is responsible for: - maintaining state of the game - handling requests from all clients participating in game - informing all clients about changes in state of the game that are visible to them # Lib ## Main purposes of lib VCMI_Lib is a library that contains code common to server and client, so we avoid it's duplication. Important: the library code is common for client and server and used by them, but the library instance (in opposition to the library as file) is not shared by them! Both client and server create their own "copies" of lib with all its class instances. iOS platform pioneered single process build, where server is a static library and not a dedicated executable. For that to work, the lib had to be wrapped into special namespace that is defined by client and server targets on iOS, so that single process is able to contain 2 versions of the library. To make it more convenient, a few macros were introduced that can be found in [Global.h](https://github.com/vcmi/vcmi/blob/develop/Global.h). The most important ones are `VCMI_LIB_NAMESPACE_BEGIN` and `VCMI_LIB_NAMESPACE_END` which must be used anywhere a symbol from the lib is needed, otherwise building iOS (or any other platform that would use single process approach) fails. See [#Wrapped namespace examples](#Wrapped_namespace_examples "wikilink"). [Lib](Lib "wikilink") contains code responsible for: - handling most of Heroes III files (.lod, .txt setting files) - storing information common to server and client like state of the game - managing armies, buildings, artifacts, spells, bonuses and other game objects - handling general game mechanics and related actions (only adventure map objects; it's an unwanted remnant of past development - all game mechanics should be handled by the server) - networking and serialization ### [Serialization](Serialization "wikilink") The serialization framework can serialize basic types, several standard containers among smart pointers and custom objects. Its design is based on the [boost serialization libraries](http://www.boost.org/doc/libs/1_52_0/libs/serialization/doc/index.html). In addition to the basic functionality it provides light-weight transfer of CGObjectInstance objects by sending only the index/id. See the [Serialization](Serialization "wikilink") page for all the details. ### Wrapped namespace examples #### Inside the lib Both header and implementation of a new class inside the lib should have the following structure: `` `VCMI_LIB_NAMESPACE_BEGIN` `` `VCMI_LIB_NAMESPACE_END` Example: [header](https://github.com/vcmi/vcmi/blob/develop/lib/CBuildingHandler.h) and [implementation](https://github.com/vcmi/vcmi/blob/develop/lib/CBuildingHandler.cpp) #### Headers outside the lib Forward declarations of the lib in headers of other parts of the project need to be wrapped in the macros: `` `VCMI_LIB_NAMESPACE_BEGIN` `` `VCMI_LIB_NAMESPACE_END` `` `` Example: #### New project part If you're creating new project part, place `VCMI_LIB_USING_NAMESPACE` in its `StdInc.h` to be able to use lib classes without explicit namespace in implementation files. Example: # [Artificial Intelligence](Artificial_Intelligence "wikilink") (AI) ## [StupidAI](StupidAI "wikilink") Stupid AI is recent and used battle AI. ## [Adventure AI](Adventure_AI "wikilink") VCAI module is currently developed agent-based system driven by goals and heroes. ## [Programming challenge](Programming_challenge "wikilink") ## [Fuzzy logic](Fuzzy_logic "wikilink") VCMI includes [FuzzyLite](http://code.google.com/p/fuzzy-lite/) library to make use of fuzzy rule-based algorithms. They are useful to handle uncertanity and resemble human behaviour who takes decisions based on rough observations. FuzzyLite is linked as separate static library in AI/FuzzyLite.lib file. # [Utilities](Utilities "wikilink") ## [Launcher](Launcher "wikilink") ## [Duels](Duels "wikilink") [Mod system proposal](Mod_system_proposal "wikilink") ## [ERM parser](ERM_parser "wikilink")