Events

Events make your scene react to people without any code. When something happens, the object does the things you listed.

WHEN  someone taps the door
THEN  swing it open over 600 ms
      disable the "locked" sign
      send the signal "door-open"

The when is a trigger. The then is a list of steps. An object can have as many events as you like, and each one runs on its own.

Add an event

1. Select the object.
2. In the inspector, click + new component and choose Events. The component starts with one event, set to Press on the object.
3. Click the event. The Event settings panel opens. To add another event, click + add event.
4. Pick a trigger, or keep Press on the object.
5. Click + add action and pick a step. The list has a search box, and the steps are grouped under Actions, Animations, States and Logic.
6. Add more steps the same way. They run in order.

Two lists to keep open

The trigger reference lists every trigger. The step reference lists every step. Both are always up to date. They show each name in the editor next to its code name for scripts: Send signal is emit_signal, and Signal is on-signal.

Triggers

A trigger is the moment an event starts. The references above list each trigger's settings. The tables below say what each one is for.

Pointer and keys

In the editor	Fires when
Press on the object	someone taps or clicks it; branches for click, press and release
Hover	the cursor moves onto the object or leaves it
Double click	two clicks on the same object within 300 ms
Long press	the object is held for 450 ms without moving
Key	a key is pressed or released
Scroll	the wheel turns; you can pick a direction
Drag	someone drags the AR content they placed
Pinch	someone pinches placed AR content to scale it
Rotate	someone twists placed AR content

Drag, Pinch and Rotate work only on surface scenes, because they act on content the visitor placed. They fire again and again while the finger moves, not just once.

Lifecycle

In the editor	Fires when
Launch	the scene starts; every object gets it
Resize	the window or screen changes size
Pause	the app or tab goes to the background
Resume	the app or tab comes back
Visibility	the object is shown or hidden

Stop sound on Pause

Sounds keep playing when a visitor switches apps, unless you stop them. Stop them on Pause, for example by switching to a state in which the sound is muted, and start them again on Resume.

AR tracking

In the editor	Fires when
Detect	the marker or surface is found
Tracking lost	tracking is lost
Placed	the visitor placed the content
VPS ready	positioning has started
VPS localized	the visitor's real position was found
VPS localization failed	the position was not found yet
VPS error	positioning could not run at all

The editor offers only the triggers your scene's anchor can produce. Detect fires once, when tracking starts, not on every frame.

A failed VPS localization is normal

VPS localization failed fires often while the visitor walks around looking for a spot the map knows. Treat it as "keep trying", not as an error to show.

Time and distance

In the editor	Fires when
Delay	once, after a delay
Every N seconds	again and again; a repeat count of 0 means forever
Distance	something comes within a distance, or moves away
Variable change	a variable gets a new value

Distance has an At start option. Turn it on if an object may already be close when the scene opens. Without it, the event waits until something moves.

States, collisions and signals

In the editor	Fires when
State active	this object enters the state you picked
State inactive	this object leaves that state
Collision	this object touches another; use Collide with to limit which ones
UI action	someone pressed a button on an interface card
Signal	another event sent a signal
Game controls	the character starts standing, moving, running or jumping

Branches

Some triggers have branches, so one event can handle every outcome. For example, one Distance event can answer both "came closer" and "moved away".

Trigger	Branches
Distance	On coming closer, On moving away
Key	On press, On release
Hover	On enter, On leave
Press on the object	On click or tap, On press, On release
Visibility	On show, On hide
Game controls	On idle, On move, On run, On jump

Each branch gets its own list of steps. A trigger without branches has one list, On activation.

Choose which objects a step affects

Every step has a Target object field.

• Leave it empty and the step acts on the object that owns the event. This is the usual case.
• Pick objects and the step acts on them instead. This is how one button opens three doors.

Taps reach parent objects

A tap, a hover or a card action reaches the object and all its parents.

So you can put one event on a group, and it catches taps on anything inside it. You do not need to copy the same event onto forty objects.

This also means:

• "tap anywhere on this panel" is one event on the panel;
• moving the cursor between two children of the same parent does not fire hover or leave on the parent, because the cursor never left it.

Some triggers work differently:

• Collision fires only on the objects that touched.
• Key, Scroll, Resize and Launch are not about one object, so every object gets them.

Events, patches and scripts hear the same taps, keys and collisions. A few triggers arrive in scripts under other names. See The ctx API.

Handle each trigger in one place

If the same object reacts to the same trigger in an event and in a script, it runs twice. When something fires twice, this is almost always the reason.

Use several keys for one event

"Jump on Space or W" is one event, not two. Click the Key field and press the first key. Then click or and press the next one. Add as many as you need.

• Each key in the list stands on its own. A modifier such as Ctrl belongs only to the key it was pressed with.
• The trigger's other settings, such as Auto-repeat, apply to every key in the list.
• A mouse button works in the same field. The list then holds mouse buttons only.

The event keeps these keys as text. An assistant or a script writes them like this:

ArrowUp        ctrl+KeyW        KeyA+KeyS        Space+double        mouse:middle

You can also use a key binding instead of a key. Set up bindings in Project settings → Key bindings. Change the key for "jump" there once, and every event that uses "jump" follows. This helps when someone asks for left-handed controls.

Steps

The step reference lists each step's settings.

Links, calls and scene changes

In the editor	Does
Scene transition	goes to another scene
Space transition	goes to another space, and to a specific scene if you pick one
Open URL	opens a link, in this tab or a new one
Open messenger	opens Facebook, VK, OK, Instagram, Telegram, WhatsApp or Viber
Call phone number	starts a phone call
Compose email	starts an email
File download	downloads a file from your project
Contact download	offers a contact card made from the fields you fill in

Open messenger needs different details for each app:

• a page ID for Facebook, VK and OK;
• a username for Instagram and Telegram;
• a phone number for WhatsApp and Viber.

Show, hide and change objects

In the editor	Does
Show / hide object	shows or hides the targets; on a scene, it makes that scene active
Set state	switches to a state you saved, smoothly if you set a duration
Override properties	applies a few values once, like a temporary state

Animation

In the editor	Does
Play animation	plays an animation from the timeline, with loop mode, repeats, speed and delay
Stop animation	stops one

Play animation can start an animation that belongs to any object. So one button can start a sequence that moves several things at once.

To move, fade or recolour something, make an animation in the Animation panel, then play it with this step. For a single change, Set state with a duration is enough.

Projects made earlier can also have the Transformation, Opacity, Material, Bone transform and Built-in animation steps. They still run in those projects, but the editor no longer offers them. Material, for example, blends the targets' colour, opacity, glow and surface settings toward a saved material, and keeps each slot's type and textures.

Movement

In the editor	Does
Follow object	keeps following another object; you set distance, offset, smoothing and speed
Look at object	turns to face something without moving
Stop following	stops following and looking
Fly along path	travels along a path
Stop path flight	stops the path flight

Logic

In the editor	Does
If — otherwise	checks a condition, then runs one of two lists of steps
Set variable	sets a variable, adds to it, or toggles it
Send signal	sends a signal to the selected objects or the whole scene
Wait, then	waits, then runs the steps inside it

Pointer

Lock pointer hides the mouse cursor and lets the scene use its movement. First-person games need this, so the cursor does not leave the window. Release pointer gives the cursor back.

Triggers and steps from plugins

A plugin added to your project can bring its own triggers and steps. They appear in the lists under the plugin's name, and you use them like the built-in ones.

• They are there only in projects the plugin is added to.
• A plugin's trigger can have settings. The event then runs only when they match. Leave a setting empty to react every time.
• If the plugin is removed from the project, its triggers never fire and its steps are skipped.

To make your own, see Runtime code.

Add a condition

A condition is a step: If — otherwise. You can put one inside another to get more than two outcomes.

Choose what the step checks in the Condition field:

In the editor	Checks	Fields you fill in
Always	nothing; it is always true	—
Variable	a variable's value	Variable, Compare, Value
Distance	how far this event's object is from another object	Object, Compare, Threshold
State	which state another object is in	Object, State
Visibility	whether something is visible	Object, Expected
Chance	a random chance	Threshold, as a percentage

How values are compared:

• 3 is read as a number, true as yes/no, and anything else as text.
• == and != check for an exact match.
• >, >=, < and <= compare numbers.

Variables, signals and timers

Variables last for one visit. They start empty each time someone opens your project. To give them starting values, set them in an event with the Launch trigger. A script sees the same variables as globals.

Signals let one event start others without copying steps. For example, several events can listen for level-complete, and any event can send it. If a signal keeps sending itself, it stops after eight rounds, so the scene does not freeze.

Timers (Delay and Every N seconds) start when their object turns on and reset when it turns off. When the object turns on again, the count starts over. Missed ticks are not fired all at once.

States

A state is a saved look of an object: its position, colour, visibility and more. The Set state step switches to it. With a duration, the change is smooth.

Use states for a switch, a highlight, or a door that is open or closed.

While a state is selected, your edits go into it

If one of the object's states is selected, changing the object changes that state. This is what you want when you build states. It is confusing if you forgot a state was selected.

More in States.

Re-tracking

In AR scenes, each event has a re-tracking mode. It sets what happens when the marker is lost and found again:

• start the steps over right away;
• never start them again;
• start them again once the current steps have finished.

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Next: Animation — make things move.