.DT Reaction Handler Discworld Creator Help Reaction Handler Name .SP 5 5 /obj/handlers/reaction - Handler for specifying reactions in mixtures .EP Description .SP 5 5 The reaction handler is used to specify what happens when different substances are combined. The handler is called by the event_enter() function in the corresponding container. The database of reagents and corresponding reactions is stored in text files, which are loaded by the data initializer (/obj/handlers/data). .EP Terminology .SP 5 5 To avoid confusion, the following terms have the following meaning. .EP .SO 5 15 -30 reagent An object that, when mixed with another reagent in sufficient proportion, will cause a reaction to occur. reaction A sequence of events that occurs when two reaction-causing reagents are mixed in sufficient proportions. The generally result is a decrease in the amounts of the reagents, the creation of a new object, and optionally the printing out of an informative message to the player(s). result The object created as the end product of the reaction. transient A reagent that has a limited lifetime. Generally used for "special effects" in the course of a reaction. continuous An object that inherits /obj/cont_medium. Only continuous objects can be reagents. Each reagent is identified by its "medium alias". .EO Reaction File Format .SP 5 5 The reaction files are the files that define the reaction database. To keep things modular, this section can be found in the obj.reactions help file. .EP Functions .SP 5 5 There are basically only three functions that are called from outside the handler. .EP .SI 5 void check_reaction( object a ) .EI .SP 10 5 This is the function that needs to be called when a continuous object enters an appropriate container. It's usually called from event_enter(). The parameter is the object being added. The function checks it against every other continuous object in the container, checks the reaction database for a match, and, if there is sufficient quantities of both reagents, causes the specified reaction to occur. .EP .SI 5 mixed *query_reaction( string name_a, string name_b ) .EI .SP 10 5 This will return a mixed array, containing all of the parameters specified for the reaction matching the two given reagents. It is pretty much obsolete now that the database is stored in nicely-formatted files, but someone may find a use for it. .EP .SI 5 void dump( string a, string b ) .EI .SP 10 5 This will write out the reaction database in a fairly-readable format. If 'b' is null, all reactions whose first reagent matches 'a' will be printed. If both 'a' and 'b' are null, the entire database will be printed. Note that the order of 'a' and 'b' must be alphabetical. This is useful for debugging, but not much else. .EP .SP 5 5 If this_player() has the property "debug_rh" defined with a non-zero value, various debugging messages will be printed during the reaction. This has proven to be extremely useful. .EP Files .SI 5 /obj/reactions/*.rcn (Note: the previous version of the reaction handler used *.rct; the suffix was changed to avoid confusion) .EI See also .SI 5 obj.reactions obj.reagents.transient /obj/reactions/*.rcn .EI
