Home For Builders Scripting Tutorials Using Trigger Events

Using Trigger Events

Intended Audience:
By David Gaider

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Again, make sure that any actions you wish to be caused by the trigger are sent to the appropriate targets via AssignCommand... or else you are telling the trigger, itself, to do something, and there is very little that a trigger can do on its own.

Trigger Event Listing

Event: OnClick, trigger: if you want a trigger that will cause an effect when it is clicked upon by the player, a script must be entered in this area. Most types of area transitions use this event (although a trigger that is set up as the 'Area Transition' type can make use of the wizard to do so). who triggered it? Use GetClickingObject() to return the player object who clicked on the trigger.

Event: OnEnter, trigger: any object that crosses the 'border' of the trigger will set off this event. who triggered it? Use GetEnteringObject().

Example: the following OnEnter trigger script will jump every member of the party who is in the same area to the waypoint tagged "JUMP_HERE".

NWScript:
void main() { object oWP = GetObjectByTag("JUMP_HERE"); object oParty = GetFirstFactionMember(GetEnteringObject(), TRUE); // cycle through valid player character party members while (GetIsObjectValid(oParty)) { // and if they are in the same area if (GetArea(oParty) == GetArea(GetEnteringObject())) { // jump the party member to the waypoint AssignCommand(oParty, JumpToObject(oWP)); } // get the next party member oParty = GetNextFactionMember(GetEnteringObject(), TRUE); } oParty = GetFirstFactionMember(GetEnteringObject(), FALSE); // now cycle through all non-player party members (like familiars) while (GetIsObjectValid(oParty)) { // and if they are in the same area if (GetArea(oParty) == GetArea(GetEnteringObject())) { // jump the party member to the waypoint AssignCommand(oParty, JumpToObject(oWP)); } // get the next party member oParty = GetNextFactionMember(GetEnteringObject(), FALSE); } // now jump the entering player to the waypoint // this line may not be necessary... including it // just to make certain the original PC jumps AssignCommand(GetEnteringObject(), JumpToObject(oWP)); }

Event: OnExit, trigger: whenever an object crosses the boundary of the trigger to leave the trigger, who triggered it? Use GetExitingObject() to return the exiting creature.

Example: this OnExit trigger script sends a command to any exiting giant to return to a waypoint.

NWScript:
void main() { object oWP = GetObjectByTag("RETURN_HERE"); object oCreature = GetExitingObject(); // if the exiting creature is a giant if (GetRacialType(oCreature) == RACIAL_TYPE_GIANT) { // tell it to stop what it's doing AssignCommand(oCreature, ClearAllActions()); // and move to the waypoint AssignCommand(oCreature, ActionMoveToObject(oWP)); } }

Event: OnHeartbeat, trigger: like other heartbeats, the heartbeat of a trigger activates every 6 seconds. A trigger, however, is not quite the same as another object... it is only 'active' when something is within its bounds or it has been clicked upon. You cannot place a trigger and give it a heartbeat script to constantly issue orders... if you want something to do that, use an invisible placeable object, instead.

Event: OnUserDefined, trigger: again, this event will only fire if a UserDefinedEvent has been specifically sent to the trigger via the command SignalEvent.