Documentation
Interactivity (logic nodes)
Logic is how your experience reacts. In the Nodes tab you wire events (things that happen) to actions (things to do) - no coding needed.
How it works
Each node is a card. You connect an event node's output to an action node's input by dragging a wire between their dots. When the event fires, the connected actions run - and you can chain several actions in a row.
Right-click the canvas (or use the palette) to add a node. Nodes are colour-coded - events in amber, actions in sky blue.
To work with several nodes at once, hold Shift and drag on empty canvas to box-select, or Shift-click (Ctrl/Cmd-click also works) to add nodes to the selection. A selection moves together when dragged, and Delete removes it - right-click for the same option.
Events
| Event | Fires when… |
|---|---|
| On Scene Start | the scene first appears (the target is found, or you arrive via Go To Scene). |
| On Tap | the user taps the object you choose (a 3D object or an on-screen UI Overlay element). |
| On Collision | two chosen objects touch - see Collisions below. |
Actions
| Action | What it does |
|---|---|
| Go To Scene | Switch to another scene, with an optional transition (fade, scale, slide, spin) and duration. |
| Play Sound | Play an imported audio clip (optionally looping). |
| Stop Sound | Stop a playing sound - every playing copy of the chosen audio clip stops and rewinds. |
| Play Video | Start playing a chosen video object. |
| Stop Video | Stop a chosen video object and rewind it to the start. |
| Play Animation | Play an animation clip on an object (a keyframe clip or a model's embedded animation). |
| Stop Animation | Stop a playing animation, freezing it in place. |
| Show Object / Hide Object | Reveal or hide an object. |
| Delay | Wait a number of seconds before the next action in the chain runs. |
Note
A worked example
To make an object appear, play a sound, wait, then jump to the next scene when tapped:
- Add an On Tap node and choose the object.
- Wire it to Show Object → Play Sound → Delay (2s) → Go To Scene.
Variables, maths & logic
Three more node categories let you build cleverer behaviour - keeping a score, doing a sum, or making a decision. The palette groups them under collapsible headings you can fold away when you are not using them.
A variable is a named value your experience can remember and change while it runs - a score, a counter, or an on/off state. Create variables in the Variables panel on the left: give each a name, a type (Number, Text or True / False), and a starting value. A variable can be scene-local (resets each time its scene begins) or global (shared across scenes for the whole session).
These categories work with two kinds of wire:
- Flow wires (as before) decide what runs next.
- Value wires carry a number, text or true/false value from one node's output into another's input - shown in blue below.
| Category | Nodes |
|---|---|
| Variables | Set Variable (put a value into a variable) and Get Variable (read its current value). |
| Operators | Value (a fixed value), Math (add / subtract / multiply / divide / remainder), Compare (equal, less than, greater than… → true/false), and And / Or / Not. |
| Logic | If (run the True or False branch), While (repeat while a condition holds), and For (count from a start to an end value). |
To show a variable on screen, add a Text element in the UI Overlay and set its Show variable (live) option - the text then displays the value and updates the instant it changes, perfect for a live score.
Note
Collisions: when two objects touch
The On Collision event fires when two objects bump into each other.
- Select each object and tick Collisions in the Inspector - both objects need it on.
- Add an On Collision node and choose Object A and Object B.
- Wire it to whatever should happen - a sound, a score change, a scene switch.
It fires once when the objects' boxes first overlap, and again only after they separate and touch once more - so holding them together won't retrigger it. The order of A and B doesn't matter. Collisions are for 3D scene objects, not on-screen UI Overlay elements.
Note
Tip