Built-in Nodes

The nodes you construct, and what distinguishes each.

Core Nodes#

Node	Purpose	Signals
`Node`	Base node specifying `enabled`, `priority`, and `children`.	`onMount`, `onUnmount`, `onSceneResize`
`ColliderNode`	Registers its `Shape` with the nearest `CollisionDetectionNode`.	`onCollisionStart`, `onCollisionEnd`
`CollisionDetectionNode`	Holds a `CollisionDetection` arena.	-
`FpsNode`	Tracks a rolling-window average frame rate in `fps`.	`onFpsChange`
`ShapeNode`	Draws a `Shape`.	-
`SizedNode`	Base node with a size, used for shapes, sprites, and more.	-
`SpriteNode`	Animates a `Sprite`. See Sprites.	`onFrame`, `onLoop`, `onFinish`
`TextNode`	Draws text with `TextPainter`, wrapping to fit.	-
`TimerNode`	Tracks time to power its signal.	`onTrigger`
`TransformNode`	Base spatial node with a `position`, `scale`, and `angle`.	-

Notable Core Nodes#

TransformNode is the base spatial node. It carries a mutable position, scale, and angle, and reports absolutePosition for its place in the scene rather than in its parent.

final turret = add(TransformNode(position: Vector2(120, 40)));

turret.angle += 0.5 * dt;
turret.distance(target); // Between absolute positions.

SizedNode extends TransformNode with a size and an anchor. Shapes, sprites, layouts, and text are all sized nodes.

Additionally, the collision, input, and layout systems all start with SizedNode. Each one depends on a node that doesn't merely exist in space, but actually occupies it as well.

Effect Nodes#

See Effects.

Node	Purpose	Signals
`EffectNode`	Base node for time-driven effects, with a `cleanup` and `reset`.	`onFinish`
`CombinedEffect`	Runs its effects together, finishing once every one has.	`onFinish`
`ControlledEffect`	An effect driven by an `EffectController`.	`onStart`, `onProgress`, `onMax`, `onMin`
`FollowEffect`	Moves a `PositionOwner` toward what it follows, at a `speed`.	`onFinish`
`SequentialEffect`	Chains its effects, adding the next once the previous ends.	`onFinish`
`SpinEffect`	Spins an `AngleOwner` by `speed`, every tick, forever.	-
`VelocityEffect`	Moves a `PositionOwner` by `velocity`, every tick, forever.	-

Input Nodes#

See Inputs.

Node	Purpose	Signals
`InputNode`	Base hit area for gestures.	-
`TapInput`	Recognizes taps.	`onTapDown`, `onTapUp`, `onTap`, `onTapCancel`
`DragInput`	Recognizes drags.	`onDragStart` , `onDragUpdate` , `onDragEnd` , `onDragCancel`
`HoverInput`	Recognizes mouse hover.	`onHoverEnter`, `onHoverExit`

Layout Nodes#

See Layout.

Node	Purpose	Signals
`LayoutNode`	Base node for laid-out nodes.	-
`BoxNode`	Claims a region, placing children under a shared padding and alignment.	-
`FlexNode`	Lays its children out along a `direction`, like Flutter's `Flex`.	-
`RowNode`	Lays its children out horizontally, like Flutter's `Row`.	-
`ColumnNode`	Lays its children out vertically, like Flutter's `Column`.	-