GetPlayerCameraTargetActor

new bool:ActorHandsup[MAX_ACTORS];

public OnPlayerConnect(playerid)
{
    EnablePlayerCameraTarget(playerid, true);
    return 1;
}

public OnPlayerUpdate(playerid)
{
    // Find out what actor (if any) the player is LOOKING at
    new playerTargetActor = GetPlayerCameraTargetActor(playerid);

    // If they ARE looking at ANY actor
    if (playerTargetActor != INVALID_ACTOR_ID)
    {
        // Store the player's weapon so we can check if they are armed
        new playerWeapon = GetPlayerWeapon(playerid);

        // Get the player's keys so we can check if they are aiming
        new KEY:keys, updown, leftright;
        GetPlayerKeys(playerid, keys, updown, leftright);

        // If the actor hasn't put its hands up yet, AND the player is ARMED
        if (!ActorHandsup[playerTargetActor] && playerWeapon >= 22 && playerWeapon <= 42 && keys & KEY_AIM)
        {
            // Apply 'hands up' animation
            ApplyActorAnimation(playerTargetActor, "SHOP", "SHP_HandsUp_Scr",4.1,0,0,0,1,0);

            // Set 'ActorHandsup' to true, so the animation won't keep being reapplied
            ActorHandsup[playerTargetActor] = true;
        }
    }
    return 1;
}