skills/pixijs/pixijs-skills/pixijs-scene-container

pixijs-scene-container

Installation
SKILL.md

Container is the general-purpose node of the PixiJS v8 scene graph. It holds children and applies transforms, alpha, tint, and blend mode to its whole subtree. Every display object you make will either be a Container you're building a branch on, or a leaf (Sprite, Graphics, Text, Mesh) that you nest inside one.

Assumes familiarity with pixijs-scene-core-concepts.

Quick Start

const group = new Container({
  label: "hero-group",
  x: 200,
  y: 150,
  sortableChildren: true,
});

const body = new Sprite(await Assets.load("body.png"));
const head = new Sprite(await Assets.load("head.png"));
head.position.set(0, -40);
head.zIndex = 1;

group.addChild(body, head);
group.pivot.set(group.width / 2, group.height / 2);
group.scale.set(1.5);

app.stage.addChild(group);

Related skills: pixijs-scene-core-concepts (scene graph mental model, masking, layers, render groups), pixijs-scene-sprite / pixijs-scene-graphics / pixijs-scene-text / pixijs-scene-mesh (leaf objects that go inside containers), pixijs-events (eventMode, hit testing), pixijs-math (Matrix, toGlobal/toLocal detail), pixijs-performance (cacheAsTexture, culling, render groups).

Core Patterns

Constructor options

const container = new Container({
  label: "world",
  x: 100,
  y: 50,
  scale: 2,
  rotation: Math.PI / 4,
  alpha: 0.8,
  visible: true,
  tint: 0xffaa00,
  blendMode: "add",
  sortableChildren: true,
  isRenderGroup: true,
  origin: { x: 0, y: 0 },
  boundsArea: new Rectangle(0, 0, 1920, 1080),
});

All Container options (position, scale, tint, label, filters, zIndex, etc.) are also valid here — see skills/pixijs-scene-core-concepts/references/constructor-options.md.

The Container constructor uses assignWithIgnore to bulk-copy every field in the options object onto the instance except children, parent, and effects. Any public property of Container is a valid constructor option: cullable, cullArea, mask, filterArea, eventMode, hitArea, and so on. The options block above groups the most common ones; see the shared reference above for the full list.

isRenderGroup: true promotes the container to its own render group so its transforms are applied on the GPU rather than recomputed per-child on the CPU. Use it on stable sub-trees (large static worlds, UI layers). Don't overuse; most scenes don't need explicit render groups and too many hurts performance. Profile before promoting. See pixijs-scene-core-concepts/references/scene-management.md.

sortableChildren: true causes children to be re-sorted by zIndex at the next render. See zIndex below.

origin is a first-class v8 transform helper: an ObservablePoint that acts as a rotation/scale center without moving the container. Where pivot shifts the projection of the local origin in parent space (so changing it displaces the object), origin leaves position alone and simply rotates/scales around the specified local point. Accepts PointData, a single number (applied to both axes), or can be set live via container.origin.set(x, y). Setting both pivot and origin on the same container produces compounding behavior and is discouraged; pick one.

boundsArea forces getBounds() to return a fixed rectangle instead of recursively measuring children; it is a performance win for containers with hundreds of cheap, predictable children.

cullable and cullArea are valid constructor options (the assignWithIgnore pass copies them like any other field), but they are documented in pixijs-performance because culling setup is a performance concern rather than a scene-graph concern.

Leaves vs containers

const parent = new Container();
const sprite = new Sprite(texture);

parent.addChild(sprite);

Only Container (and subclasses intended to hold children, like RenderLayer) should have children. Sprite, Graphics, Text, Mesh, ParticleContainer particles, and DOMContainer content are leaves by convention in PixiJS v8. Wrap them in a Container whenever you need to group things: give the container the layout logic and keep the leaves pure visual data. Adding children to a leaf logs a deprecation warning and is scheduled to become a hard error.

Adding and removing children

const parent = new Container();

parent.addChild(a, b, c);
parent.addChildAt(d, 0);
parent.swapChildren(a, b);
parent.setChildIndex(c, 0);

parent.removeChild(b);
parent.removeChildAt(0);
parent.removeChildren();

parent.removeChildren(0, 2);

addChild accepts any number of children and returns the first one. Children render in array order: index 0 is drawn first (behind), the last index is drawn last (in front). addChildAt inserts at a specific index; setChildIndex moves an existing child; swapChildren exchanges two children's positions.

removeChildren(beginIndex?, endIndex?) removes a slice and returns the removed array.

Calling addChildAt with a child that already belongs to the same container silently moves it to the new index. No added / childAdded / removed / childRemoved events fire, because the parent-child relationship didn't change. Events only fire when the child comes from a different parent (or from no parent).

For reparenting that preserves world transform (so the child doesn't visually jump), use reparentChild / reparentChildAt. For swapping a child in place while copying the old child's local transform, use replaceChild.

Transform properties

const obj = new Container();

obj.x = 100;
obj.y = 200;
obj.position.set(100, 200);

obj.scale.set(2);
obj.scale = 2;

obj.rotation = Math.PI / 4;
obj.angle = 45;

obj.pivot.set(50, 50);
obj.skew.set(0.1, 0.2);

obj.alpha = 0.5;
obj.tint = 0xff0000;
obj.visible = false;
obj.renderable = false;
  • position, scale, pivot, skew are ObservablePoints. Assigning scale = 2 is valid and sets both axes.
  • rotation is radians; angle is degrees; they are aliases that stay in sync.
  • pivot sets the point in local space that maps to position in parent space; changing it both moves and rotates the container.
  • alpha and tint multiply down through children. blendMode applies to this container's draw instructions.
  • visible = false skips rendering and transform updates. renderable = false skips rendering but still updates transforms (use when you need getBounds() or hit-testing without drawing).

zIndex and sortableChildren

const world = new Container({ sortableChildren: true });

const ground = new Sprite(groundTexture);
ground.zIndex = 0;

const player = new Sprite(playerTexture);
player.zIndex = 10;

const ui = new Sprite(uiTexture);
ui.zIndex = 100;

world.addChild(ground, player, ui);

When sortableChildren is true, the container re-sorts its children by zIndex before the next render. Changing any child's zIndex automatically re-marks the parent as needing sort. Sort only what you need to sort; leaving sortableChildren off is cheaper. If you want full manual control, call container.sortChildren() yourself after changing zIndex values.

For render-order control that is decoupled from the hierarchy (children keep their logical parent for transforms but render at a different z), use RenderLayer. See pixijs-scene-core-concepts/references/scene-management.md.

Bounds and coordinate conversion

const bounds = container.getBounds();
console.log(bounds.x, bounds.y, bounds.width, bounds.height);

const rect = container.getBounds().rectangle;

const local = new Point(10, 20);
const world = container.toGlobal(local);
const backToLocal = container.toLocal(world);

const selfPos = container.getGlobalPosition();

getBounds() returns a Bounds object (not a Rectangle); it exposes x, y, width, height, and a .rectangle getter for APIs that need an actual Rectangle. The signature is getBounds(skipUpdate?: boolean, bounds?: Bounds) — pass true as the first arg to skip the forced transform update, and an optional Bounds instance as the second arg to avoid allocating a new one.

toGlobal(point) converts a point in this container's local space to scene-root space. toLocal(point, from?) converts from another container's local space (or global space if from is omitted). getGlobalPosition() is shorthand for parent.toGlobal(this._position).

Sizing

const sprite = new Sprite(texture);

sprite.setSize(200, 100);
const { width, height } = sprite.getSize();

setSize adjusts scale so the container's bounds fit the requested pixel size, in one operation. Setting .width and .height individually works, but each assignment triggers a separate bounds recomputation; prefer setSize when changing both axes.

Container events

const parent = new Container();

parent.on("childAdded", (child, container, index) => {
  console.log("added at", index, child.label);
});

parent.on("childRemoved", (child, container, index) => {
  console.log("removed from", index);
});

const child = new Container();
child.on("added", (newParent) => console.log("entered", newParent.label));
child.on("removed", (oldParent) => console.log("left", oldParent.label));
child.on("visibleChanged", (visible) => console.log("visible:", visible));
child.on("destroyed", (destroyed) => console.log("gone", destroyed.label));

parent.addChild(child);
Event Fires on Arguments
childAdded the parent receiving the child (child, container, index)
childRemoved the parent losing the child (child, container, index)
added the child that was attached (parent)
removed the child that was detached (parent)
destroyed the destroyed container (container)
visibleChanged the container whose visible flipped (visible)

These are emitted on the EventEmitter side of Container; do not confuse them with pointer events from pixijs-events.

destroyed fires after internal cleanup but before listeners are removed, so by the time your handler runs position, scale, pivot, origin, skew, and parent have already been nulled, and children has been emptied (length 0, but the array reference itself is not nulled). Capture any data you need from the container before calling destroy(), not inside the handler.

Per-frame updates with onRender

const container = new Container();

container.onRender = (renderer) => {
  container.rotation += 0.01;
};

container.onRender = null;

onRender runs every frame while the container is being rendered, and receives the active Renderer. Use it for lightweight animation or per-frame updates tied to a specific container. In v7 this pattern was done by overriding updateTransform, which no longer runs every frame in v8. Set onRender = null to detach the callback.

Finding and removing from parent

const player = world.getChildByLabel("player");
const enemies = world.getChildrenByLabel(/enemy-\d+/, true);

const bounds = hud.getLocalBounds();

oldSprite.removeFromParent();
  • getChildByLabel(label, deep?) — first match by string or RegExp. Pass true for a recursive search.
  • getChildrenByLabel(label, deep?, out?) — all matches. Accepts an optional reusable output array.
  • getLocalBounds() — bounds in this container's own coordinate space, ignoring parent transforms. Cheaper than getBounds() for self-contained layout math.
  • removeFromParent() — detaches this from its current parent (no-op if already orphaned).

Destroy

container.destroy();

container.destroy({
  children: true,
  texture: true,
  textureSource: true,
});

console.log(container.destroyed);

By default destroy() unlinks this container from its parent and tears down its own state. Pass { children: true } to recursively destroy every descendant; this is the usual call for killing a whole subtree. texture: true and textureSource: true additionally destroy the GPU resources referenced by leaf children (useful for sprites whose textures you loaded just for them). If cacheAsTexture is on, disable it with container.cacheAsTexture(false) before destroying.

Common Mistakes

[CRITICAL] Adding children to leaf scene objects

Wrong:

const sprite = new Sprite(texture);
const overlay = new Sprite(overlayTexture);
sprite.addChild(overlay);

Correct:

const group = new Container();
const sprite = new Sprite(texture);
const overlay = new Sprite(overlayTexture);
group.addChild(sprite, overlay);

Sprites, Graphics, Text, and Mesh are leaves. Adding children to them logs a deprecation warning now and will be an error in a future version. Always wrap them in a Container when you need grouping.

[HIGH] Expecting getBounds() to return a Rectangle

Wrong:

const rect = container.getBounds();
rect.contains(x, y); // TypeError: contains is not a function

Correct:

const rect = container.getBounds().rectangle;
rect.contains(x, y);

const bounds = container.getBounds();
console.log(bounds.width, bounds.height);

getBounds() returns a Bounds instance in v8. Its basic getters (x, y, width, height) work, but for Rectangle-specific methods like .contains() or passing to APIs that require a Rectangle, read the .rectangle property.

[HIGH] Using cacheAsBitmap instead of cacheAsTexture

Wrong:

container.cacheAsBitmap = true;

Correct:

container.cacheAsTexture(true);

cacheAsBitmap (v7 property) was renamed to cacheAsTexture() (a method) in v8. Always disable it with cacheAsTexture(false) before calling destroy().

[MEDIUM] Using container.name instead of container.label

name was renamed to label in v8. The old property still works as a deprecated alias; getChildByLabel is the v8 way to look up children by name.

[MEDIUM] Setting both pivot and origin on the same container

Pivot shifts the projection of the local origin in parent space (moves the object as a side-effect of changing the rotation center). Origin changes the rotation/scale center without displacement. Setting both on the same container produces unexpected compounding; pick one.

API Reference

Weekly Installs
235
GitHub Stars
157
First Seen
Today