Engine scripts

Before writing behavior from scratch, inspect the curated scripts shipped with the installed playcanvas package under scripts/esm/**. Discover the current set:

rg 'static scriptName =' node_modules/playcanvas/scripts/esm \
  | sed "s|.*/scripts/esm/||; s|:.*static scriptName = ['\"]|  ->  |; s|['\"].*||" \
  | sort

Read the selected file for its named export, @attribute properties, and defaults. Not every module is a Script; the parsers below scripts/esm/parsers are plain classes registered with a resource handler instead.

Only import from scripts/esm/. Legacy sibling directories depend on the global Engine namespace. After selecting a script, use find-examples to locate its matching versioned Engine example. When node_modules/playcanvas is a linked or source checkout, its examples/src/examples/ are already on disk; read them there and skip the fetch.

Check fit before integration

Compare candidates with the required behavior, approved art direction, and runtime constraints. Reuse a suitable script directly or adapt its configuration and extension points. If none fits, state the limitation and implement only the missing behavior, preserving reusable parts and their lifecycle, bounds, and input invariants.

For visual behavior, resolve an unclear art direction with the user before substantial implementation. Present references, mockups, or inexpensive variants; follow existing approval and confirm significant departures. A script's default appearance is only a starting point for assessing its fit.

Adapt the reference integration

Treat the selected script source and its closest official example as complementary references:

1. Read the source for exports, properties, defaults, fallbacks, required components, and lifecycle.
2. Read the example for assets, entity references, mesh requirements, layer ordering, scene settings,

and render-pipeline setup.

1. Integrate the selected behavior with its required components, assets, and passes. Adapt the look

to the approved direction and preserve defaults and dependencies that still apply.

1. After a rendered frame, fail on console, shader, or missing-asset diagnostics. Exercise the

behavior with real input where applicable and inspect returned screenshots from representative views at the final backbuffer density.

1. Use the example to check integration correctness and the user's approved direction to judge the

final look. Report any remaining gap.

If no matching example exists, state that and derive the integration from installed source instead of inventing it from memory.

Preserve grouped defaults

Grouped property updates differ by authoring surface. Read the selected reference and preserve defaults that are not being changed.

Read exactly one reference matching the code being edited: [direct Engine](references/direct-engine.md), [React](references/react.md), or [Web Components](references/web-components.md). Choose from imports and markup, not installed dependencies alone.