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Member Since 21 Nov 2011
Offline Last Active Jul 15 2012 06:21 AM

Posts I've Made

In Topic: Delayed execution of behavior functions in Lua/C++

11 June 2012 - 02:10 PM

This is one heck of a question. I am not familliar with luabind, so I will go over the general ideas, and maybe hit some specifics.

Aye, and thanks alot for taking the time to lay out all that - i checked this post yesterday regularly but there wasnt a reply and in the meantime i got the idea to the solution myself which is basically similar to your pseudo code - however there is a gist - first the basic schedule function was pretty easy - its just a callback which - as you said i check the time in c++ - here it is for completion

void NPC::AddSE(const luabind::objectluabind::object &fn,int millisec) {
if(luabind::type(fn) == LUA_TFUNCTION)
  ScheduledEvent sEvent;
  sEvent.eventFunction = fn;
  sEvent.time = GetMilliCount() + millisec;
void NPC::CheckForScheduledEvents() {
std::vector<ScheduledEvent>::iterator sEvent = m_scheduledEventFunctions.begin();

while (sEvent != m_scheduledEventFunctions.end())
  if(sEvent->time < GetMilliCount())
   if(sEvent->eventFunction.is_valid()) {
   // erase returns the new iterator
   sEvent = m_scheduledEventFunctions.erase(sEvent);
Now the hard part was having scheduled movie like events with delays in between for scheduled events e.g.

NPC:Say("Continue after 1sec")

That without letting the mainloop sleep! I got around this with the unique function of lua = coroutines - basically if WaitTime calls yield(x) the x will be returned to my lua_resume function - and in my code i will schedule the next call to resume after XX amount of time.

To answer your second question: The functions are in the same scope as long as they are loaded (luaL_dofile) with the same lua_State. So you can call those functions any time you want. However, I do suggest that you create tables named after each NPC behavior to hold those functions to avoid name conflicts.

Yes - thats what i want todo - is there a scope for a lua_state ? i dont like to name my functions unqiuely in each lua script - e.g. there should be no collision - how can i export one lua script to a specific scope only valid for one NPC ? Lets say all NPCs have an ID instead of doing

luabind::globals(myLuaState)["npc"] = npc;

i somehow have to put this NPC only in the scope of the loaded script - which brings the next problem if i use Lual_doFile or similar luaL_dostring(myLuaState, "code...") how put this in a scope ? I dont want that the scripts need to make namespaces or something similar - this should be safely done in c++ code. To reach the script of another NPC i would just expose an object to lua e.g. npc->GetScript()->CallFunction(luabind::object)... (I gather best practise is to have one lua_state for all NPCs and not multiple)

Any idea?

And thanks again =)

In Topic: Help me with ASM

11 June 2012 - 01:51 PM

This is a ida pro dump (CODE XREF: gives it away) - so why not use hexrays to give you pseudo c