State

The NPC's State and Condition helps the NPC decide on an ideal Schedule. At any given time the NPC will only ever be in one state. You can change the state anywhere in your NPC logic with SetState(), for instance SetState( NPC_STATE_ALERT );

The following is a list of the states.

NPC_STATE_INVALID 
NPC_STATE_NONE 
NPC_STATE_IDLE 
NPC_STATE_ALERT 
NPC_STATE_COMBAT 
NPC_STATE_SCRIPT
NPC_STATE_PLAYDEAD
NPC_STATE_PRONE
NPC_STATE_DEAD

One interesting method that deals with states is the SelectIdealState() method. This method chooses a state based on its current state and conditions.

The method implementation has a switch statement that reverts Ideal state selection to specific functions to the current state.

switch ( m_NPCState ) 
{ 
     case NPC_STATE_IDLE: 
     { 
          NPC_STATE nState = SelectIdleIdealState(); 
          if ( nState != NPC_STATE_INVALID ) 
          return nState; 
     } 
     break; 

     case NPC_STATE_ALERT: 
     { 
          NPC_STATE nState = SelectAlertIdealState(); 
          if ( nState != NPC_STATE_INVALID ) 
          return nState; 
     } 
     break; 

     case NPC_STATE_COMBAT: 
     { 
          // COMBAT goes to ALERT upon death of enemy 
          if ( GetEnemy() == NULL ) 
          { 
               return NPC_STATE_ALERT; 
          } 
          break; 
     } 

     case NPC_STATE_SCRIPT: 
     { 
          NPC_STATE nState = SelectScriptIdealState(); 
          if ( nState != NPC_STATE_INVALID ) 
               return nState; 
     } 
     break; 

     case NPC_STATE_DEAD: 
          return NPC_STATE_DEAD; 
} 

We can see the switch statement in the case of NPC_STATE_IDLE state selection will be reverted to SelectIdleIdealState() method.