Ground any answer about the WebGPU platform itself — browser support/compatibility, feature availability, limits, what's shipping or behind a flag, and exact spec behavior — in the live Chrome WebGPU docs and the W3C spec before responding, instead of answering from memory. Use whenever a question is about WebGPU as a platform rather than OGPU's own code: "is X supported in Chrome/Safari/Firefox", "are 64-bit atomics available", "what's the default maxStorageBufferBindingSize", "does WebGPU have feature Y yet", "what's new in WebGPU", "is timestamp-query / shader-f16 / float32-filterable shipping", origin-trial/flag status, or whether some API is in the spec at all. WebGPU moves fast and memory goes stale — fetch the sources first.
Fold real-time shadow mapping into an existing RenderPipeline/shader in the OGPU engine. Use whenever the user wants cast shadows, a depth-pass / shadow-map shadow, a character or mesh to drop a shadow on a floor, self-shadowing, PCF soft shadows, "make it cast a shadow", "add shadows", or real-time shadows on a custom (skinned, displaced, instanced, IBL-lit) shader. Covers the depth-only caster pass + the receiver sampling fold.
Scaffold a new OGPU example/app from scratch — a Renderer + Camera + Orbit + update loop and a single spinning cube wired through the vanilla Box primitive -> RenderPipeline -> Mesh setup. Use whenever the user wants a new OGPU example, a base/starter scene, a blank WebGPU sketch in this repo, "scaffold an app", "new example called X", "boilerplate a OGPU scene", "set me up a starting point", or just "new scene"/"new example" when OGPU is the implied target. Generates the example class + shader and wires it into src/main.js so it boots at ?src=<name>.
Fold PBR/IBL shading into a RenderPipeline in the OGPU engine. Use whenever the user wants physically based shading, IBL, image-based lighting, metallic/roughness materials, an environment-lit mesh, "make this look like a real material", or wants to combine their own custom vertex/fragment work with the engine's PBR lighting. Also use when a mesh has no textures and needs sensible fallback (factor-only) material setup.
Scaffold a new simple WGSL shader for the OGPU engine, wired for a RenderPipeline + Mesh. Use whenever the user wants to create a new shader, start a shader from scratch, add a .wgsl file for a mesh, get a shader boilerplate/template/starting point, or "make me a basic shader" / "scaffold a shader". Produces a minimal vs/fs WGSL file following the engine's reflection conventions, optionally with the JS pipeline wiring.
Ground any answer about the webgpu-utils library (greggman/webgpu-utils) in its actual API before responding. Use whenever a question or task touches a webgpu-utils function, class, or option — makeShaderDataDefinitions, makeStructuredView, createBuffersAndAttributesFromArrays, createTextureFromImage(s)/Source(s), generateMipmap, primitives.*, setStructuredView, the reflected uniform/storage views, bind-group-layout generation, attribute/buffer creation, mip generation, or anything imported from 'webgpu-utils'. In the OGPU engine this library backs RenderPipeline, ComputeShader, Geometry, Texture, and IBLUtils, so it surfaces constantly — consult it before claiming a signature, option name, default, or behavior, rather than guessing from memory. Trigger even when the user doesn't name the library, if the symbol clearly belongs to it.