pixijs/pixijs · error · Error

ParticleContainer.setChildIndex() is not available. Please u

Error message

ParticleContainer.setChildIndex() is not available. Please use ParticleContainer.setParticleIndex()

What it means

ParticleContainer.setChildIndex is overridden to throw; reorder operations must use setParticleIndex so the particle buffer ordering stays correct. The generic index setter is blocked to avoid a silent no-op that desyncs render order from storage.

Source

Thrown at src/scene/particle-container/shared/ParticleContainer.ts:668

     */
    public override getChildAt<U extends ContainerChild>(_index: number): U
    {
        throw new Error(
            'ParticleContainer.getChildAt() is not available. Please use ParticleContainer.getParticleAt()',
        );
    }
    /**
     * This method is not available in ParticleContainer.
     *
     * Calling this method will throw an error. Please use `ParticleContainer.setParticleIndex()` instead.
     * @param {ContainerChild} _child
     * @param {number} _index
     * @throws {Error} Always throws an error as this method is not available.
     * @ignore
     */
    public override setChildIndex(_child: ContainerChild, _index: number): void
    {
        throw new Error(
            'ParticleContainer.setChildIndex() is not available. Please use ParticleContainer.setParticleIndex()',
        );
    }
    /**
     * This method is not available in ParticleContainer.
     *
     * Calling this method will throw an error. Please use `ParticleContainer.getParticleIndex()` instead.
     * @param {ContainerChild} _child
     * @throws {Error} Always throws an error as this method is not available.
     * @ignore
     */
    public override getChildIndex(_child: ContainerChild): number
    {
        throw new Error(
            'ParticleContainer.getChildIndex() is not available. Please use ParticleContainer.getParticleIndex()',
        );
    }
    /**

View on GitHub (pinned to 4b141e3ced)

Solutions

Use particleContainer.setParticleIndex(child, newIndex) as the message directs.
If you only need draw order, check whether the particle container exposes a z/depth-based sort instead.
Make sort helpers container-type aware.

Example fix

// before
particleContainer.setChildIndex(p, 0);

// after
particleContainer.setParticleIndex(p, 0);

Defensive patterns

Strategy: type-guard

Validate before calling

if (container instanceof ParticleContainer) {
  throw new TypeError('Use ParticleContainer.setParticleIndex() instead of setChildIndex()');
}

Type guard

import { Container, ParticleContainer } from 'pixi.js';

function isParticleContainer(c: Container): c is ParticleContainer {
  return c instanceof ParticleContainer;
}

Prevention

Reorder particles with setParticleIndex.
Make sort/reorder helpers container-type aware.
Consider z/depth sorting where supported.

When it happens

Trigger: Calling particleContainer.setChildIndex(child, newIndex) directly, or generic sort/reorder utilities that reorder children by index.

Common situations: Sorting particles (e.g., back-to-front); porting z-order code from a Container; generic drag-to-reorder UI operating on containers.

Related errors

AI-assisted analysis of pixijs/pixijs@4b141e3ced (2026-08-12). Data as JSON: /api/errors/4f393a66147abd3c. Report an issue: GitHub.