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Conversations are a system introduced with Arma 2 and created to enhance discussions. This system allows dynamic conversations and a more fluid sentence/answer flow.

Its main advantages are:

  • The system itself waits for the sound sample to finish. No more sample time measuring and countless sleeps!
  • Conversation always flows through the appropriate channel (direct for face to face, team radio for distant team members etc.)
  • Possibility to create fully dynamic conversations
  • Transparent syntax (FSM branches allow fast and efficient edits)


.bikb extension stands for "Bohemia Interactive Knowledge Base" as it was originally used only for storing an AI unit's memory of what it has seen. This file defines sound files and subtitles to use. Important

The extension has no impact on the file in any way. An example is available below.



  • FSMs are executed only once after each received sentence while conversation event handlers are constantly fired (usually every frame) as long as you're pointing at somebody.
  • If the unit is controlled by AI, the assigned FSM is executed. If it's player-controlled, it fires the event handler. If this is a MP mission and the unit is playable, you will want to use both the FSM and the event handler.


A conversation topic has to be added (via kbAddTopic) to units for them to be able use it (via kbTell for example). Once the unit said wanted sentences (via kbWasSaid), the topic can be removed (via kbRemoveTopic).

Manual conversation example

miles   kbAddTopic ["briefing", "kb\briefing.bikb", ""];
shaftoe kbAddTopic ["briefing", "kb\briefing.bikb", ""];

shaftoe kbTell [miles, "briefing", "shaftoe_briefing_H_1"];
waitUntil { shaftoe kbWasSaid [miles, "briefing", "shaftoe_briefing_H_1", 3]; };

miles kbTell [shaftoe, "briefing", "shaftoe_briefing_M_1"];
waitUntil { miles kbWasSaid [shaftoe, "briefing", "shaftoe_briefing_M_1", 3]; };

hint "Conversation ended.";
// you could here - eventually - use kbRemoveTopic to "clear" the units if the topic is not required anymore. This is not mandatory.

.bikb examples

"Interrupted" event

The left-side conversation menu (with the list of possible sentences) can be closed via backspace at all times. If you want to handle this event as well, you have to add new sentence class called Interrupted into your .bikb file. It can then be used as a standard _sentenceId in the script.

.bikb simple example

class Sentences
	class example_01
		text = "Hello Bret."; // sentence subtitle
		speech[] = { "\Sound\jemaine01.ogg" }; // sound file path
		class Arguments {};
	class example_02
		text = "Oh, hello Jemaine.";
		speech[] = { "\Sound\bret01.ogg" };
		class Arguments {};
	class lastWord
		text = $STR_TranslationReference; // has to start with "STR_"!
		speech[] = { "\Sound\bret01.ogg" };
		class Arguments {};

// Don't worry about these.
class Arguments {};
class Special {};
startWithVocal[] = { hour };
startWithConsonant[] = { europe, university };

.bikb advanced example

See Words configuration and below for more details.

class Sentences
	class AirstrikeRequest 
		text = "%team requesting close air support at grid %location ";
		speech[] = { %Team, RequestingCloseAirSupportAtGrid, %Location }; {{codecomment|// words are defined in Cfg/RadioProtocol/Words
		class Arguments 
			class Team { type = "simple"; };
			class Location { type = "simple"; };

class Arguments {};
class Special {};
startWithVocal[] = { hour };
startWithConsonant[] = { europe, university };

Conversation FSM example

note receives the same arguments as the Conversation Event Handler (_this, _from, _sentenceId, _topic).
See also: FSM, FSM Editor

Conversation Event Handler

The Conversation Event Handler is not an Event Handler as we know them. This is a sqf script file that will be executed with each sentence. Following parameters are passed:

  • _this: Object - receiver or listener of the sentence. One of the units that had this particular script assigned via kbAddTopic
  • _from: Object - the unit that told the sentence
  • _sentenceId: String - the sentence this unit is reacting to. Defined in .bikb in class Sentences
  • _topic: String - topic name used in kbAddTopic

Conversation Event Handler script example

// here we will be storing all the sentences from which the player will choose (the menu on the left side of the screen)
// if there is only one option in the array, the sentence will replace the "Talk to" action name

BIS_convMenu = [];

// we want the player to be able to approach his buddy and talk to him via the action menu.
// we need to check:
// if the player is pointing at his buddy
// if the player is not answering any of his buddy's sentences
// if the player hasn't told him hello already
// then we add that array to BIS_convMenu - the parameters are mostly self-explanatory:

if (_from == buddy1 && _sentenceId == "" && !(_this kbWasSaid [_from, _topic, "hello1", 999999])) then {
	BIS_convMenu = BIS_convMenu + [["Say hello.", _topic, "hello1", []]];

// here we make the unit say the proper sentence based on the one he just received
// switch-case-do is used here but it is completely up to you how to evaluate it (if-then etc.)

switch (_sentenceId) do
	case "hello1": {
		_this kbTell [_from, _topic, "hi_how_are_you"]
	case "good_you": {
		_this kbTell [_from, _topic, "fine_thanks"]
	case "what_do_we_do_today": {
		// here the player will have 3 answers to choose from:
		BIS_convMenu = BIS_convMenu + [["Football.", _topic, "choose_football", []]];
		BIS_convMenu = BIS_convMenu + [["Bike.", _topic, "choose_bike", []]];
		BIS_convMenu = BIS_convMenu + [["Arma II.", _topic, "choose_arma2", []]]

// return the sentence list pool

See also