You want to shoot the player. But where do you aim? The head<\/em> seems a likely spot. But remember the I-can’t-see-you-you-can’t-see-me problem we had with detection<\/a>. If the player is crouching behind cover with their butt sticking out, the AI needs to be smart enough to forgo the headshot and aim for the sticking-out stuff. If not, players will eventually realize they can take cover behind ridiculously small things – anything that can cover their head. <\/p>\n Weapon Behavior<\/strong><\/p>\n
<\/td><\/tr><\/table>The obvious thing to do is to make sure the AI will [seem to] live under the same rules as the player. Effective range, crosswind, weapon accuracy, and movement all need to impact the accuracy of the shot. A lot of games seem to have two sets of rules: One for players and one for AI’s. STALKER was really bad about this, in that weapons were far more accurate in the hands of enemies than they were in the hands of the player. Each bad guy most likely had a single “accuracy” rating that was applied to all situations. You would be crouching, with a good-quality weapon, with the bad guy perfectly lined up, but the bullet spread would cause you to miss. The bad guy would be not just standing but walking<\/em>, using the same weapon but in worse condition, and would hit you more often than you hit him. On easy difficulty. This was flat-out unfair and frustrating.<\/p>\n
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<\/td><\/tr><\/table>A struggling human player will generally begin aiming with large, sweeping motions, making smaller and smaller adjustments until they settle on the target, even if it’s moving. The target can quickly change relative velocity to foul this process. The result is human players weaving and hopping to keep their relative velocity as unpredictable as possible. For AI, the accuracy should start out very low on a moving target and go up to near 100% as the AI draws a bead on the player. It doesn’t make sense for the AI to miss 30% of the time when they’re shooting at an immobile player at point blank and also missing 30% of the time when they’re shooting at a sprinting player at thirty meters. Just having them miss 30% of the time (with the number going up as distance increases) will not produce believable behavior. More importantly, it will homogenize enemy combat effectiveness, thus making player choices less meaningful (why bother to engage in a way that’s unfavorable to the weapons the enemy has, if they will perform just fine anyway? Might as well just charge headlong into every fight) and thus less 
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