Omar SobhandClaude Opus 5
4358964c05
55 of 85 role skill bindings pointed at skills that were never authored,
so 10 of 11 team templates bound a smaller context bundle than their role
prompts assumed. Three roles bound nothing at all (gpu.bench_engineer,
threejs.shader_author, threejs.perf_engineer) while their prompts described
procedures they had no way to read.
The loader comment at team_template_loader.rs:167 already diagnosed this —
snake_case slugs in TOML against kebab-case skill files — and it was
half-fixed: the kebab names were corrected, the snake_case ones left.
It was invisible because both existing tests assert authored ⊆ referenced
(30/30, green) and the second explicitly declines to check the other
direction. So the failing half was the half nobody asserted.
Resolved every name by one of three explicit choices:
- 23 skills authored where the role genuinely needed the procedure
(gpu, threejs, research, analysis, frontend, mobile, backend, platform)
- renames onto authored skills where one existed in substance, including
the four-near-duplicate cases that collapse onto one real skill
- 22 aspirational references deleted — a binding an agent cannot read is
a promise, not a capability
Two tests now hold it. The unit test checks referenced ⊆ authored against
the files. The new integration test runs both loaders in boot order and
asserts the bindings survive the trip through the database, which is a
different question: resolution goes through skills_catalog rows, so a skill
file that exists but fails to ingest still leaves the role empty.
Negative controls: the unit test failed naming all 55; the integration test
fails naming the exact role when one name is reverted.
threejs.shader_author and .perf_engineer gained a second and third skill
after the collapse — pin_in_context pins idx < 2, so a role left with one
skill silently pins less than the policy intends.
Co-Authored-By: Claude Opus 5 <[email protected]>
2.4 KiB
name, description, when_to_use, tags
| name | description | when_to_use | tags | ||
|---|---|---|---|---|---|
| shader-authoring-glsl-wgsl | Writing GLSL and WGSL shaders that compile on both, and the precision and uniform traps that only appear on some hardware. | You are the shader author on a three.js/WebGL team, writing or porting a shader. |
|
GLSL and WGSL are the same ideas, spelled differently
WebGL2 takes GLSL ES 3.0; WebGPU takes WGSL. Porting is mostly mechanical, and the mechanical parts are not where the bugs are.
| GLSL ES 3.0 | WGSL | |
|---|---|---|
| entry | void main() |
@fragment fn fs_main(...) -> @location(0) vec4f |
| varyings | in/out at global scope |
struct fields with @location(n) |
| uniforms | uniform block |
var<uniform> in a bind group |
| texture | texture(sampler2D, uv) |
textureSample(t, s, uv) — texture and sampler are SEPARATE |
| vec | vec3 |
vec3f (alias of vec3<f32>) |
The separated texture/sampler split is the one that changes structure: WGSL binds them independently, so a GLSL shader using four samplers becomes four textures plus (often) one shared sampler.
Precision is not decoration
mediump in a fragment shader means at least 10 bits of mantissa, and on
mobile GPUs it means exactly that. A computation that is fine on a desktop
where mediump is silently promoted to 32-bit will band, banding-clamp or
NaN on a phone.
Rules that avoid the whole class:
- World-space positions and time accumulators are
highp. Always. Amediumptime uniform visibly stutters within minutes of page load. - Normalise in
highp, then downcast. - Test on a real mobile device or an emulator that honours precision. Desktop Chrome will not show you this bug.
Uniforms are a budget
Each uniform, varying and texture unit is a hardware-limited slot, and the
limits are much lower than desktop defaults suggest (MAX_VARYING_VECTORS can
be 8). Pack related scalars into a vec4 rather than declaring four floats, and
query the limits rather than assuming.
Shader compile errors are silent by default
three.js logs a compile failure to the console and renders black. That is indistinguishable from a material bug, a camera bug or a culling bug. When something renders black, check the shader log FIRST — it is a two-second check that eliminates a large fraction of the search space.
Keep a flat-colour fallback: a shader that fails to compile should show magenta, never black. Black is a colour the scene might legitimately be; magenta is not.