JSDSH currently uses two different class-trees (one for the crafty/graphical objects, one for "game" objects),
although this (and everything marked with (*)) is subject to change in the future.

The Crafty-Classes that are not defined by the library (included from jsds_crafty.js) are:

Thing: A base class, providing the Canvas- and Color-Mechanisms and positioning.
Creature: Creatures are everything tha may attack and move (that is, players and monsters)
          Additional to Thing, this class provides mechanisms for moving the element by mouse or arrow-keys,
          collision-control to prevent overlaps, and bindings.
          (*) Furthermore, every creture-object has a variable set to the associated game-object.

The following additional functions and variables are defined in jsds_crafty.js:

last_sel: contains a reference to the game-object associated to the last clicked object.
end_init(): This function should be called as last after an adventure is loaded and initialized. Usually,
            when using arrow key control, crafty moves every EACH object where it is activated.
            end_init disables this control for each object of type "Creature", and sets a hook needed to work
            around a bug in crafty.
reset_bug(): resets the problems with a bug in crafty that causes a key-down-event to be (constantly) triggered
             when the JSDSH-Tab is the one the browser falls back to after closing another tab.
             (Strange, I know…).
             If this happens, DON'T CLICK ANOTHER OBJECT! Open the JS-console and run reset_bug() manually.
             If you accidentily clicke ONE other object, it is still possible to get back to the old state
             Manually reset_bug(), de- and refocus the window, and run reset_bug() once more.