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Faces of War Overview Q&A

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Please tell us, why you are so proud about the AI in 'Faces of War'.
First of all, AI is the offspring of our long-term work. Second reason, we received at the end a very qualitative and broad abilities of AI.
From the very beginning AI in 'Faces of War' was based on use of actual information. AI in 'Faces of War' doesn't cheat. It means that our AI doesn't use the info, which is not available for a unit in reality. To put it simple each unit has "eyes", "ears" and "memory". The units can see and hear. Mainly it has influence on the decisions of AI. However the eyesight and hearing have their limitations, there are usual ones. The enemy can disappear, having hidden behind a structure or a ground fold. Even in this situation the AI would behave adequate. Once noticed the enemy, a soldier can chase it, basing on his memory about the enemy though without seeing it. The units can exchange information about the availability and location of enemy forces. It looks as follows, if a soldier from the enemy squad noticed you, he can sound the alarm and the whole army would attack you. You should give up reckoning to lure the enemy out of the base one by one and kill them quietly. By the way it is quite hard to do it quietly, because the shots will be heard and the attacker will be searched around.
Besides conscious decisions, AI in 'Faces of War' has basic self-preservation instinct. It helps to make the behaviour of soldiers more natural. The units can de-fend differently: they hide, if they are severely injured; they flee from thrown grenades and give way to moving vehicles. In principle this all is natural and the player perceives it in this way. On a battlefield players will see not just dummies, which execute orders and move along the given trajectories.

All the above mentioned is surely important. However we needed something else to create real hostilities in the gaming environment. The soldiers on the battle field don't run singly and don't make decisions on their own, because we created an additional ‘level' of soldier thinking – the squad thinking. The decisions are made in the squad not only by the unit individually, but there are also commands of the squad leader. This form of a squad represents a complete military unit, which actions are harmonious and organized.

How does the AI in 'Faces of War' differ from AI in a typical RTS? Was it difficult to integrate the AI during the game development?
First of all I'd like to mention that AI in 'Faces of War' can not be called strategic in the direct meaning of this word. It is rather tactical. This difference alone is important. Tactical AI gives the soldiers opportunity to fight tactically. The main factor is not, who has got more soldiers, or how well they are armed. Such factors as terrain features, positions of objects, which soldiers can use as cover also play an important role. These are not scales, which can estimate the number/quality of soldiers and draw a conclusion about the battle outcome. The tactics suggests a lot of parameters, which influence the outcome of each even small battle.
Thus, the whole system of AI is based on "honest" data, just to let the player feel that tactics works naturally. If we had used common principles of AI-design, the player would feel embarrassed. There is no unified Master Brain in our system, which sees and knows everything and sends its units to most profitable places.
Each unit is a separate brain, which has feelings and senses. This brain makes decisions individually and puts them into life. Even if soldiers can tell each other about the enemy, it doesn't mean that their decisions will be similar. It is rather difficult to put it other way, but the AI design of soldiers will allow them to communicate with each other. As a result it looks like rather conscious actions - very realistic.
If we take into consideration the fact that soldiers are able to act in squads, we get a rather realistic view. Groups of soldiers act all together, they shoot, move around the terrain, kill enemies or withdraw fighting, hide in houses or in ruins. With the whole complexity of AI system the behaviour of soldiers looks natural and doesn't arouse any admonitions. You can be sure, in 'Faces of War' you'll fight not against scripts and waypoints, but against a thinking enemy, who behaves in appropriate manner.
The development of AI of this level was not a piece of cake. Only in early versions the system was developed using a well-grounded scheme. The majority of developments, which followed afterwards were made with the help of the "cut and try method". We invented a new feature, realized it in a draft version and tested it. In course of time we either deleted this feature or improved it to the state of a final version. Such iterative work allowed us to understand our goal clearly at the each stage of production. However it was required to have the AI as a part of the game, otherwise we'd fail to carry out continuous tests "as they are", i.e. directly in the game.

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