On NPC Mod Creation and Compatibility, while being the least intrusive to core game resources

UNDER CONSTRUCTION

Created by Idomeneas

Please do not edit this, unless you found a mistake. In that case inform me first.

The purpose of this wiki is to help the community tackle one of the most important problems we face: compatibility between all our mods, in particular those mods that introduce NPC followers.

I'll share with you my approach to handling companions, based on what I have done with my mod, Valeria Addon, my experiments and experience. My goal has always been to be the least intrusive to the game core resources (meaning don't change them at all if possible), while having the companion behave appropriately in most parts of the game.

What I'll talk about here works for Patch 1.02. If you got Awakening or Patch 1.04 you'll see weird behavior and this approach might have to be altered.

Everything you see below is done WITHOUT changing game resources. Let us begin.

Understanding the game mechanics and the module event script

We first need to discuss how the game makes use of scripts, and in particular our module event scripts (every mod has one). Everytime something happens in the game, e.g., you open or close the inventory, talents, skills, or world map gui, all the module event scripts you have installed are fire and processed (probably in the order the mods where installed) as well as the core game scripts (typically these are processed first).

So if we want to capture the behavior of our NPC follower or a major event of the game it can be done here, e.g., the PC selected or dropped the follower in the partypicker, you begin travel, or the PC just finished talking to everyone at the gates in the climax, or the game is over and we're at the slideshow.

This game stucture is indeed brilliant since it allows the main game and all mods installed to handle and process the same event, say EVENT_TYPE_BEGIN_TRAVEL or EVENT_TYPE_MODULE_HANDLE_GIFT or EVENT_TYPE_WORLD_MAP_CLOSED and so forth.

What we can't and can do

The only major resource we have to change is the partypicker, otherwise our NPC's won't show up. There is a way around this(item 4 below).

If you want your NPC to interject in the middle of a major dialog, that dialog resource has to be changed (I can't see any way around this one).

The thing to keep in mind is that everytime something happens in the game, certain flags from core game resources are set. We can capture when these are set and continue the process appropriately.

In this way, I'll show you how we can do the following (I've done these for my mod Valeria, WITHOUT changing any core game resources, I'll use her as a reference):

1) Valeria banters with the party randomly WITHOUT changing any original game scripts.

2) Valeria accepts specific gifts WITHOUT changing the game scripts.

3) Valeria is in a nightmare area WITHOUT changing the game scripts.

4) Valeria has a dialog option to eliminate problems with partypicker compatibility. If she doesn't show up in the partypicker she can still be picked up or sent back to camp.

5) Valeria has her own dialog after major cutscenes (where appropriate) of the game WITHOUT changing resources of the game.

6) Valeria appears in all camps (basic camp, Arl Eamon's estates, post coronation), most cutscenes from the original game and at the city gates WITHOUT changing resources of the game.

7) Valeria behaves appropriately if the PC gets captured WITHOUT changing resources of the game.

8) Slideshow post coronation WITHOUT changing the resources of the game.(Haven't included it in my mod yet, but it's done)

What do we need?

Well, basic knowledge of the toolset and scripting.

a) The NPC mod event handler, say "valeria_event_handler"

b) A plot to hold all our NPC flags, call it "valeria_npc_hire". In the handler we should have the include:

#include "plt_valeria_npc_hire"

c) We need the following basic FLAGS: PARTY_VALERIA_IN_PARTY, PARTY_VALERIA_JOINED, VALERIA_CHECK_RUNIT

These are there to handle Valeria(is she in party?, has she joined? do we need to run the script? it has to be done if we're in a camp site. you'll see what script)

d) Other flags to set when needed: VALERIA_WYNNE_KILLED, VALERIA_RESPONSE_TO_BAD, VALERIA_ENTER_FADE, VALERIA_HAS_NIGHTMARE_A, VALERIA_HAS_NIGHTMARE_B, VALERIA_HAS_NIGHTMARE_C, VALERIA_SLOTH_DEMON_ATTACKS, VALERIA_SLOTH_DEMON_DEFEATED, VALERIA_WYNNE_KILLED_AT_CULLEN, VALERIA_DEN_CAPTURED_PC_CAPTURED, VALERIA_CLI_MAIN_PC_FINISHED_SETTING_FINAL_PARTY, VALERIA_EPI_JUMP_TO_SLIDE_SHOW, VALERIA_FIGHTING_ARCHDEMON

If you drop the valeria_ prefix (FOR YOUR MOD USE A DIFFERENT PREFIX EVERYWHERE) you'll recognize some flags from the original game. Everytime those are set, we'll need to set a corresponding flag in our NPC plot, so we don't run things twice.

I'll tell you which plots from the main game we need depending on what we're trying to do.

Basic structure of the module event handler

//core includes here

//core plot includes

//valeria function, plots etc, includes

#include "plt_valeria_npc_hire"

//constant definitions here

//function definitions here

(all this part 1)

void main() {

   object oPC = GetHero(),me=OBJECT_SELF,ohire;
   event ev = GetCurrentEvent();
   int nEventType = GetEventType(ev);
   //function calls here, other important checks (part 2)
   //capture events
   switch(nEventType)
   {
    .....(part 3)
   }

}

//functions here (part 4)

For what follows, I'll break the event script into four parts for quick reference: Includes, (Main) Body, (Event) Handling, Functions

Capturing Main Campaign Event/Flag Changes, the function check_plot_changed()

The next script can be placed in the event handler, and allows us to capture and process main plot changes.

I'll do this structure a first time here

In 'includes' add:

void check_plot_changed(object oVal);

In 'body' add:

... object oVal=UT_GetNearestObjectByTag(oPC,"valeria_npc"); ...

check_plot_changed(oVal); ...

In 'functions' add:

//check if plot flags changed and act appropriately

void check_plot_changed(object oVal) {

   object oPC=GetHero();//if NPC has not joined return
   if (!WR_GetPlotFlag(PLT_VALERIA_NPC_HIRE, PARTY_VALERIA_JOINED))
       return;

//here depending on which core flag changed, act appropriately .....

}

We will be changing this function appropriately below, depending on what we wish to do.

Random banters

What we need

A dialog resource, say "valeria_random_banter.dlg", a script "valeria_random_banters.nss" and a plot "plt_valeria_random_banters"

You will notice that they are done in order of appearance in the .dlg file. Of course one can change that. Meaning if Alistair is in, all his banters will go through first, then Moriggan, then Leliana ,etc, the way I had them in my file. To change that you can add a random chance to see if you initiate dialog with the party member.(see the script below, it is trivial)

valeria_random_banters.nss

First create this script. You can see what flags you need in plt_valeria_random_banters below (basically a flag for each companion you want Valeria to banter with). Alternatively, you can use the core plots to check who is in the party, but I find this more efficient, since we got full control over the script and plot resource.

//file valeria_random_banters.nss

#include "wrappers_h"

#include "plt_valeria_random_banter"

void main() {

   WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, ALISTAIR_IN_PARTY, FALSE);
   WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, MORRIGAN_IN_PARTY, FALSE);
   WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, LELIANA_IN_PARTY, FALSE);
   WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, WYNNE_IN_PARTY, FALSE);
   WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, ZEVRAN_IN_PARTY, FALSE);
   WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, DOG_IN_PARTY, FALSE);
   object [] arParty = GetPartyList(GetHero());
   int i;
   int nSize = GetArraySize(arParty);
   int which=Random(nSize)+1;
   if(GetTag(arParty[which]) == "gen00fl_alistair")
       WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, ALISTAIR_IN_PARTY, TRUE);
   if(GetTag(arParty[which]) == "gen00fl_morrigan")
       WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, MORRIGAN_IN_PARTY, TRUE);
   if(GetTag(arParty[which]) == "gen00fl_leliana")
       WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, LELIANA_IN_PARTY, TRUE);
   if(GetTag(arParty[which]) == "gen00fl_wynne")
       WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, WYNNE_IN_PARTY, TRUE);
   if(GetTag(arParty[which]) == "gen00fl_zevran")
       WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, ZEVRAN_IN_PARTY, TRUE);
   if(GetTag(arParty[which]) == "gen00fl_dog")
       WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, DOG_IN_PARTY, TRUE);

}

//to add a random chance for the party member to banter with Valeria you can simply change ...

   if(GetTag(arParty[which]) == "gen00fl_dog" && Random(10)==1)
       WR_SetPlotFlag(PLT_VALERIA_RANDOM_BANTER, DOG_IN_PARTY, TRUE);

...

This way it won't circle through all the banters of Alistair, then Morrigan's etc, but it will skip them with some probability (90%).

Changes in valeria_event_handler

I'll do this structure again(last time), the rest will be the same:

In 'includes' add:

void valeria_banter();

In 'body' add:

//valeria banter: run this only if valeria is in active party

   if (WR_GetPlotFlag(PLT_VALERIA_NPC_HIRE, PARTY_VALERIA_IN_PARTY))
       valeria_banter();

In 'functions' add:

void valeria_banter() {

   if(Random(400)!=1)//1 in 400 chance to start banter
       return;
   if(GetCombatState(GetHero()))//don't start if in combat
       return;
   object [] arParty = GetPartyList(GetHero());
   int i;
   int nSize = GetArraySize(arParty);
   if(nSize<=2)//if only valeria and the PC no banter
       return;
   for(i=0;i<nSize;i++)
       if(!ClearAmbientDialogs(arParty[i]))
           return;
   object oval=UT_GetNearestObjectByTag(GetHero(),"valeria_npc");
   UT_Talk(oval,GetHero(),R"valeria_random_banter.dlg");

}

Structure of the file valeria_random_banter.dlg

Everything should be set to AMBIENT. First notice where we call the random_banter_script.

Now, notice how we structure all the npc's we want Valeria to banter with. First is Alistair, if he's in the party, and so forth.

Notice that once a banter starts, it will never be shown again.

An example with 3 NPC's (this is a dog banter with Valeria, and Zevran, if he's in the party(notice the condition C, using the valeria_random_banters flag) he joins in).

End game Slideshow

What we need

The core plot file epipt_main, contains the variable EPI_JUMP_TO_SLIDE_SHOW, which is set once you talk to the guard post-coronation at the doors and the end slideshow begins.

Add the variable VALERIA_EPI_JUMP_TO_SLIDE_SHOW in the companion VALERIA_NPC_HIRE plot, so we only do this once. We also need the dlg file with the slide dialog and pretty pictures. I use my main dialog file for this, you don't have to: valeria_npc.dlg

To implement:

In includes, add:

#include "plt_epipt_main"

In the function check_plot_changed() add:

... //valeria in the epilogue

   if (WR_GetPlotFlag(PLT_EPIPT_MAIN,EPI_JUMP_TO_SLIDE_SHOW) && !WR_GetPlotFlag(PLT_VALERIA_NPC_HIRE,VALERIA_EPI_JUMP_TO_SLIDE_SHOW))
   {
       WR_SetPlotFlag(PLT_VALERIA_NPC_HIRE,VALERIA_EPI_JUMP_TO_SLIDE_SHOW,TRUE);
       BeginSlideshow(R"valeria_npc.dlg");
   }

...

Structure of the file valeria_npc.dlg

Note the check to see if the end game slides have run. I'm assuming the game ends after, so this runs only once and it's done. If another mod has the same setup (with different names for plots, flags etc) that mod script should run and continue the slideshow until the bioware credits run.

Now display the appropriate text and picture (it is set on the slideshow tab) depending on which flags from the companion mod are true (depending on whether the PC helped the companion and so forth)

Valeria at the gates in the climax

In the climax, you get a last chance to switch your party, where everyone parades in front of you. Well... the right behavior is to first talk to Riordan, he opens the partypicker, you may choose whom you want and then the parade begins.

Once you close the partypicker, Valeria will speak before/or after everyone else is done, so it runs smoothly. Now since many mods might skrew up the partypicker (by not including certain chars), you might have Valeria not showing up. At this stage you won't be allowed to use the dialog option anymore, to get her to join.

You could be intrusive here and force her in the partypicker, but if everyone does it we're in trouble. So I don't reccommend it and I didn't implement it this way. It is best to handle partypicker compatibility by including all waypoints for all NPC's in the char_stage.

What we need

The plot plt_clipt_main contains the important flag CLI_MAIN_PC_FINISHED_SETTING_FINAL_PARTY, and as it says, it becomes true when the PC is done setting the final party. So, create in the VALERIA_NPC_HIRE plot the flag VALERIA_CLI_MAIN_PC_FINISHED_SETTING_FINAL_PARTY, so we do this only once.

To implement:

In includes, add:

#include "plt_clipt_main"

In the function check_plot_changed() add:

//valeria at the gates

   if (WR_GetPlotFlag(PLT_CLIPT_MAIN,CLI_MAIN_PC_FINISHED_SETTING_FINAL_PARTY) && !WR_GetPlotFlag(PLT_VALERIA_NPC_HIRE,VALERIA_CLI_MAIN_PC_FINISHED_SETTING_FINAL_PARTY))
   {

//this bolded part takes care of her, regardless of whether you added //her to the party. this way she will show up when your companions //defend the gate, choose another location of course

       location ValeriaLoc;
       object curArea=GetArea(oPC);
       ValeriaLoc=Location(curArea, Vector(123.24, 717.48, 0.0), -64.92);
       AddCommand(oVal, CommandJumpToLocation(ValeriaLoc));        

WR_SetPlotFlag(PLT_VALERIA_NPC_HIRE,VALERIA_CLI_MAIN_PC_FINISHED_SETTING_FINAL_PARTY,TRUE);

       if(WR_GetPlotFlag(PLT_VALERIA_NPC_HIRE, PARTY_VALERIA_IN_PARTY))
       {

//this flag is important for the slideshow at the end

           WR_SetPlotFlag(PLT_VALERIA_NPC_HIRE,VALERIA_FIGHTING_ARCHDEMON,TRUE);
           WR_SetFollowerState(oVal, FOLLOWER_STATE_ACTIVE);
           SetLocalInt(oVal, CREATURE_REWARD_FLAGS, 0);  //Allows the follower to gain XP
       }
       if(!WR_GetPlotFlag(PLT_VALERIA_NPC_HIRE, PARTY_VALERIA_IN_PARTY))
       {
           WR_SetPlotFlag(PLT_VALERIA_NPC_HIRE,VALERIA_FIGHTING_ARCHDEMON,FALSE);
           WR_SetFollowerState(oVal, FOLLOWER_STATE_AVAILABLE);
       }
       SetObjectActive(oVal,1);
       UT_Talk(oVal,oPC);
   }

Changing the Valeria dialog appropriately: valeria_npc.dlg

Use the flag here, and depending on whether the PC added Valeria to the party, follow a different path.

She complains if she wasn't selected to fight the archdemon, and she has every right.