This type of callbacks is used when one entity collides with another, for examples you use it to check if the Player has entered a script area.


asParentName - the parent entity, most of the times it's "Player"
asChildName - the child entity or the object (script areas for example) the parent entity / Player collides with
asFunction - the name of the function that gets called if the entities collide
abDeleteOnCollide - if the callback should be removed once the function has been called
alStates - either
1 = function is called when asParent enters asChild
0 = function called when entering and leaving asChild
-1 = function called when leaving asChild

Callback function syntax:

Example script

In this script, once the Player leaves (alState = -1) our script area Script_Area_Door the callback function Door_Function is called.
abDeleteOnCollide set true means the callback then is removed.

Door_Function then uses SetSwingDoorClosed to close the door mansion_door and play an accurate door slam sound.

If you want to remove the callback before it has been called (maybe because something different happened), use

This is the callback function that is used if you want to make item interaction with the player's environment possible.


asName - literally name of the callback, use explained down below
asItem - the item the player has selected from his inventory, can be a key, a crowbar, anything
asEntity - the entity the item is supposed to be used on, in case of keys = a door, or script areas
asFunction - the function the callback triggers
abAutoDestroy - the same as abDeleteOnCollide, removes the callback when set true

Callback function syntax:

Example script

One of the most common ItemCallbacks, which opens a locked door. key_library is our key which is used on the door library_door. This triggers the function Open_Library which opens the door with SetSwindDoorLocked and plays a nifty unlock sound.
You can get very creative with this kind of callbacks, remember the padlock puzzle from Frictional's prison level?

If you want to remove this callback, use


This is what asName is for. If you don't plan on doing so, just leave it empty, like in my example script.

These are callbacks that refer to one specific entity only and include Interact-, LookAt- and .. just Callbacks. They are set in the entity tab of the entity in the level editor, but you can also add them in your script.

EntityCallback

asName - name of the entity
asCallback - callback function

You may now ask yourself - "What is this used for? When is this even called?" Well, the secret lies in the callback function:


type can be three things: OnPickup, Break, OnIgnite
You check these with an if (type = x) condition!

OnPickup = this is used when the entity is picked up, so mostly for items if you want to make something happens when, for example, the player picks up a key (how Frictional triggers some monsters, for example).

Break = when the entity breaks (glass bottles, but also doors that monsters may break down!)

OnIgnite = this is used for (surprise!) lamps or candles

Example script

I've written BookPickUp in the callback text field of an item, so there's no need to use SetEntityCallbackFunc here. So when the if condition has checked if string &in Type is OnPickup, it activates an area called TeleportChangeItemArea. I rarely use this type of callbacks, but there are occasions where they are necessary.

EntityLookAtCallback

asName - name of the entity the player looks at
asCallback - callback function; as you can see, the syntax of these is pretty minimal
abRemoveWhenLookedAt - .. self-explanatory by now

This type of callback checks if the player looks at a specific entity. In a horror game, I think you can guess what these are used for.

Callback function syntax (this is where the fun begins):

alState can be either 1 (player is looking) or -1 (player is not looking).
You don't have to use an if condition, in that case the callback function will automatically trigger when the player looks at the entity. Keep in mind that entities can be script areas too, so if you want to do something behind the player.. look at the example script!

Example script

So.. how this works: Let's assume we have a little room. One half of that room is covered with a script area, which has the EntityLookAtCallback Suprise_Monster, which only triggers when the player does NOT look at the script area, which means not looking at one half of the room which ensures the player has his back to the area when Heinz, our grunt, spawns there and attacks, with a little help from ShowEnemyPlayerPosition, the player.
Some of you may ask: "But what if the player even isn't in that room? Wouldn't the monster instantly spawn when the player is just somewhere else?" and I'd say "You're absolutely right!". The trick is only activating the callback when the player enters the room and deactivating it once he leaves. Use an EntityCollideCallback with an area that covers the whole room and checks when the player enters and leaves the area or the room!

EntityPlayerInteractCallback
asName - name of the entity the player interacts with.. you should get this by now
asCallback - callback function
abRemoveOnInteraction - self-explanatory

This one is simple. It calls its callback function once the player interacts with an entity, which could be opening a door / drawer, picking up a chest etc.

Callback function syntax:

Example script

Once the player interacts (meaning grabbing it / opening it) with Pandora's box, we play an eerie sound which initiates the end of the world!