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In designing the Lua / Mud trigger system we have tried to keep it as consistent with mobprogs as possible so it will be familiar to existing builders. The mobprog trigger types were also necessary to convert the old ROM areas to V3 as their flow is based on these trigger types. There are a number of new trigger types and options available with triggers, details are listed below.

Character Triggers

Character triggers are the type you will be most familiar with, and most work the same. Some have additional arguments that are passed through to Lua. The important thing to note is that most triggers in place so far exist only to support the conversion of mobprogs to Lua or for the academy. The Lua system can trigger on pretty much anything - post to the Aardwolf Lua forum if you have a need to trigger on something unavailable here.

Room Triggers

Room triggers are split into two main types: Room triggers that act as arbitrary commands on a room. For example, allowing a player to 'pick apple' in the Orchard or 'board' the train in lands of legend. The second type of trigger is actions performed by the room itself - perhaps a room damages chars on entry if they dont have enough resists to fire, or an "onrepop" trigger runs when the area repops, basically allowing you to create your own reset types. At the time of writing, only the first type of triggers are in place. These are listed below.

Room triggers/progs have some important differences from standard mobprogs. Firstly, each trigger type has an additional (optional) argument for 'actor'. The actor is the key of a mob that much be in the room for the prog to be able to run - this mob then becomes 'self' as if a mobprog had been called. Lands of Legend uses this - 'board' only works if the conductor is there. The academy progs that wait for you to type a command before continuing also use this - they will only run if the trainer is present.

Another important difference with room progs is that unless an actor is given (see above), there is no "self" when the prog runs. Many of the existing luaprog functions require/assume that 'self' is present and either will not run at all (echo - WHO is doing the echo in this case?) or require an extra argument (oload - requires char to put the object on if there is no self).

op south
ope south
open south
open s
open so
ope sou
...
unblock south
unblock s
unb s 
... etc ...

if charg == nil then
   --- No argument given, let MUD command handle it.
   return false
end

if room.south.open == 1 then
   --- Room is already open. Let MUD command handle it.
    return false
end
	
--- is ch.arg a prefix or match on 'south' ?
local i = string.find("south","^"..string.lower(charg))
if i ~= nil then
   --- Trying to open south
   if ch.race ~= RACE_GIANT then
      send(ch,"Ony a giant is strong enough to clear the way South.")
      return true -- Block the open command.
   else
      return false -- Let the open command continue
   end
else
   --- Not trying to open south. Let the command continue
   return false
end

No   Trigger Type Program       Phrase               Actor
==   ============ ============= ==================== ==============
 1 - Cmdabbrev    test-141      open                     

Object Triggers

See the Object Progs page for a list of object prog triggers.