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How events work

Event sheets are the no-code way to make a game work. They follow the model of Construct: a sheet is a list of events, and every event is

WHEN / IF   <conditions>     all must be true (or any, in an OR block)
THEN        <actions>        run from top to bottom
            <sub-events>     only checked when the parent event ran
Two events from the tutorial
Two events from the tutorial

The events above, read aloud:

  1. WHEN Player collides with Cylinder → DO destroy the Cylinder, add 1 to Score, set the label to "Score: " + Score.
  2. WHEN Score = 3 → DO set the label to "You win!".

When do events run?​

  • The sheet runs every frame (about 60 times per second), top to bottom.
  • An event whose conditions are all true runs its actions — every frame they stay true. Score = 3 above sets the label again and again; that is fine.
  • Trigger conditions (marked ⚡) are different: they run once, at the moment something happens — On start of scene, On collision with, On clicked, On created, On timer finished…
  • Every X seconds and Trigger once while true help when you want something to happen once or at a rhythm, not every frame.

Where events live​

Open Logic. Each scene runs one event sheet, chosen in This scene runs. A new project has Main events. Tap a sheet to open it.

The Logic tab
The Logic tab

Object types and tags​

  • An object type is an object name. All objects called Coin — including copies and objects created while playing — are instances of the Coin type.
  • A tag acts like a family: #coin means every object that has the coin tag, whatever its name.

Picking — the key idea​

A condition about an object picks the instances that match it. The event’s actions and sub-events then only affect those instances.

  • Player collides with Coin picks the one coin that was touched, so Coin: Destroy destroys only that coin — not all coins.
  • Enemy: Compare instance variable health ≤ 0 picks only the enemies with no health left, so Enemy: Destroy removes just those.
  • If an action targets an object type that no condition picked, it applies to all instances of that type.
  • Pick nearest, Pick farthest, Pick random and For each let you choose instances yourself.

Kinds of rows​

RowWhat it is
EventConditions + actions + optional sub-events.
ElseRuns when the event directly above did not run. It can have its own conditions (“else if”).
GroupA named, foldable folder of events. It can be switched on/off while playing (Set group active).
CommentA yellow note for yourself. The game ignores it.
VariableDeclares a variable, e.g. number Lives = 3.
FunctionReusable events with parameters, run with Call function.
ScriptA few lines of JavaScript inside the sheet.

See Advanced events for else, OR, groups, functions, loops, timers and scripts.

Values are expressions​

Every value you type in an event is an expression: 10, Score + 1, "Score: " + Score, Player.x, random(1, 6). Text needs "quotes". See Expressions.

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