Baukasten represents a possible implementation of the object model as described by Britt L. Hannah.
The object model consists of five major classes:
* action
* entity
* form
* state
* space
this implementation, however, differs a little from what's described in that it introduces another major class; entitytype. which basically serves the purpose of being a template for the entities. the entitytype consists of states with const values. one instance of this class can be assigned to more than one entity, saving memory.
should, however, the value of this state be changed, a mechanism is triggered and a new state object is instantiated and filled with the new value, hence preserving the original value of the entitytype.
chains of types can be built, through assigning a parent entitytype to another:
entitytypes: basic_unit, knight entity: unit
in this example a unit can be built with basic_unit as its initial type. further down in the game -- with enough experience points -- unit becomes a knight, hence the type has to be changed. before just setting the type of the unit, one can -- there's no obligation though -- take the old type getType() and assign this as the parent type to the new type. now the unit has the states of basic_unit and those of the knight.
where entity class is the one to be the main hub in this model. an entity represents the object in a game, be it a unit, a tree, a car, what have you. however, it has to be modelled to represent all of this objects. this is done through assignment of states as its properties, other entities, and actions as its behaviour.
states can be set through the addState() methods, actions can be assigned with the addAction() method.
form is the graphical representation of a component. it communicates with the graphics backend through defined api, which enables it to draw basic objects (e. g. line, rectangle, point, ...), images and text.
so far only 2d is supported by the graphics api.
grab the sources from bitbucket, github or gitorious.
to build the sources create a build directory in the root directory of Baukasten and start cmake, followed by make && make install, to install the libs, and include files:
cd Baukasten
mkdir build && cd build
cmake ..
make && make install
in order for the documentation being built and installed the following sequence of commands is needed
cd Baukasten
mkdir build && cd build
cmake .. -DWITH_DOC=1
Baukasten supports Lua as its scripting language. action classes can be instantiated with a path to the lua script. whenever the action is executed the given script is executed.