Improv

Improv: A System for Scripting Interactive Actors in Virtual Worlds

What

In this paper Improv is stated as “An Expert System For Authors”, what it is is an interactive system that lets authors of various abilities create lifelike animated character interactions.

Why

Improv was created with the intention of creating tools that would be able to convey a sense of psychological engagement. There are other tools which the paper discusses but the general consensus is that they were trying to improve on these tools to make it easier for non programmers to create these believable interactive animations.

How

The high-level description of how Improv works is that they have used an “english-style” scripting language and a network distribution model. However this does not describe the architecture, the diagram below is from the paper and shows the three main elements in the architecture. 

The Behaviour Engine simply put is the mind of the actor, it is where decisions about triggering animations and higher-level capabilities are taken care of. 
The Animation Engine controls the body of the actor, layering and blending animations to convey the mood of the actor.
The Geometry is the model that is manipulated into the expressions and actions.
Underneath these engines there are two other parts of the system that gives the actor a more believeable lifelike feel. Degrees of Freedom(DOF) values are what control the actor over time and the smooth transitions between actions. Coherent Noise is also a technique used, it is applied so as to avoid complex simulation models. It adds the slight movements that living beings make when doing anything. An example is the controlled randomness of eye blinking, wandering gazes, or the small motions of a character trying to maintain balance.
While that is the basic underlying of the system, how to use the system is by using the aforementioned “english-style” scripting language. The first example below shows the script needed for an actor to make a curtain call showing triggering actions. While the second example shows the actor making a choice, once a choice has been made it is executed as if it was an action chosen by the author.

Examples:

define SCRIPT "Curtain Call"
{ "walk to center" }
{ continue until { my location equals center } }
{ "turn to camera" }
{ continue until { "turn to camera" is done } }
{ "bow" }
{ continue for 3 seconds }
{ "walk offstage" }

SCRIPT "Rock Paper Scissors"
{ choose from { "Rock" "Paper" "Scissors" } }

There is also the ability to control more than one actor, the diagram below shows a blackboard between one actors system and the others. The blackboard gives the impression to users that all the actors know what all the other actors are doing and gives the ability of being able to respond quickly and in a meaningful way.
 


The second diagram included here demonstrates the how the user can interact with the actor, the levels of abstraction are needed to allow the author to control what the user can do. 
 

There are many ways to control the actors another important technique is the implementation of Decision Rules. The system uses the decision rules to weight each object that has been passed to it allowing the actor to “intelligently” make the right choice.

So What

In the paper the authors finish discussing the possibilities of Improv. Their goal is to make it into a commercial tool set with plenty of documentation for ease of use. They also plan to add voice recognition and behavioural sub-systems which allows the user to control goals, moods, attitudes, and relationships between the actors using spoken English. They finish by stating a big list of areas where they believe this system would be useful, including Role Playing Games, shared virtual worlds, digital puppetry, computer guides and companions among more. 

Improv is an interesting system that looks like it would be beneficial in many areas as the authors stated. However the ability for non programmers to use it effectively is still a point for me as demonstrated by the script above it is simple looking  but as it gets more complex and larger will non programmers be able to understand what they are doing and how to achieve their goal in an effective way?

JESS Language

Provide a brief summary for your manager as to whether your company could be using JESS language as a platform for an online entertainment product. You can use the brief introduction as a starting point for your investigation.

JESS is an expert system language which uses the Rete algorithm to match patterns efficiently.  This can be used with our online entertainment product in many ways. 
As a rule based system it will store our catalog and use pattern matching to intelligently filter the products for each customer based on similar people and their previous purchases. It does this by having a set of rules that relate to the relationship between the products and customers which will deduct what the customer might prefer.
JESS can also be used with our resource planning systems and at the order validation side of the production. 
However there we would have to use JESS as a servlet as it does not always work as an internet applet and some of the functionality may be lost when used with certain browsers.  
I would still recommend the use of it as it can continually be built on and customised with ease.

Recursive Transition Networks

Can you use Recursive Transition Networks as Smoke and Mirrors for apparent Intelligence in the context of Game AI, if so how, if not why?

Recursive Transition Networks(RTNs) are used for language parsing to create “well formed” sentences. RTNs can be used outside of games to generate essays and papers that have sensible sentences but don’t necessarily make sense when read together. In games it is used as a speech language parser to give NPCs a sense of intelligence when speaking to the player. Not only can they be used for speech but also the generation of appropriate rules and equipment.
As an example of speech parsing in games Bot Colony, the player can speak freely and the game will try to respond in a human intelligent manner. Compared to popular games being released now which use dialogue trees, voice commands, or other fixed ways of answering, Bot Colony is superior in technology using deeper processing than the other techniques above. 
How well do the Bots in Bot Colony actually talk?

By the technology you would expect that they could converse well however they may get confused as English is a complicated language to follow.
Despite that Bot Colony shows that RTNs can in fact be used in games.

20Q

Starting if necessary extending the resources introduced in these slides, investigate the technique behind the 20Q game can it be (how) implemented in a computer game ?

20Q works by using question matrices and weighting analysis. The questions and the possible answers are all weighted in different ways allowing 20Q to guess closer each time you play as it takes into account previous games because it learns mainly by repetition. The website also uses the rough location, age, and gender of the player, giving it the added help of searching through other similar users and seeing what their thoughts were when they played.
20Q is an artificial neural network and as such is continually learning using techniques similar to humans and as such seems to reach conclusions as humans would by weighting the answers and using heuristics.
To a certain extent the technique behind 20Q could be used in games, an example would be applying it to enemies in a shooter. This could make the enemies more likely to use tactics making them harder to kill, however there is a certain limit as the player doesn’t want to reach a point where they can’t defeat the enemies because they are too clever. It may be better for the players overall enjoyment if they used the the 20Q neural technique but with restrictions. Restrictions which could be applied through difficulty settings allowing players to enjoy the game on their own level. 
Another problem would be the likelihood of the player playing the game after they have finished it, if there was a 2nd playthrough inbuilt in the game e.g. Borderlands, they are more likely to but most of the time they are not. In games where there are 2nd playthroughs the technique could add that extra element where you may have to adopt a totally new style of play.
Overall the technique could be applied and make game play a lot more exciting however there is a fine line between challenging but still fun and too difficult.

Table Reference
Robin Burgener, "Artificial neural network guessing method and game"