Stage 0 of the five-stage plan in reviews/02-application-code-triage.md: the
shared pre-renderer alignment that has to land before slice 4d writes renderer
code, so the runtime foundation and Format Specification revision 0.8 cannot
drift while three slices are built on top of them. Nothing here draws.
The JSON Schema's `visuals` definition was a Phase 0 stub of `camera`,
`systems`, and `passes`. It is replaced by the real container - scene, layers,
systems, fields, camera, effects, and the exhibit-scope `automation` array that
17.3 previously rejected while 19.1 authorized. Fourteen new definitions cover
visual objects, paints, styles, transforms, behaviors, distributions, trails,
links, automation tracks, the spawn container, and visual components, and
`components.visual` is no longer an unconstrained object. Structural exclusions
carry the contract's own prohibitions: no `id` on a visual object, no `links` on
an emitter, no `trail` on a render object, and none of the four spawn-only
lifecycle names at a system's top level.
src/runtime/visual-contract.js is new and plays the role audio-contract.js
plays for sections 14-16: the primitive, system, behavior, field, distribution,
blend, filter, and post-effect vocabularies; the post-effect parameter tables
with their ranges and pass costs; the centralized ceiling table of 19.5 split
into authoring bounds and runtime ceilings; and matchVisualTarget, which
resolves a path against the four section 8.1 visual target families and
distinguishes a dangling reference from a target that exposes no capability.
src/runtime/visual-validation.js is new and validates the shared surface: the
visuals container, the scene model including the conditional viewport `fit`
rule, layers including the rule that a present layer map makes a system's
`layer` required, the common system fields and the `spawn` container,
procedural fields including the conditional noise `direction`, the post-effect
chain, and visual automation with its two declaration scopes, its automatable
registry, its loop modes, and its authoring bound. Type-specific system fields
are carried through unvalidated and are tightened by 4d, 4e, and 4f.
The resolution engine now exposes the four visual families. `target()` returns a
capability record with a per-family stage table, replacing the hardcoded
`namespace === 'buses'` test for the automation and modulation stages, so a
boolean system `visible` correctly has neither. Visual bases sample once from
the `visual` stream domain at the exhibit-scope instantiation boundary, fall
back to their documented defaults - including the scene center for an
unauthored camera position - and clamp through the shared 8.1 safety stage, so
a `focalLength` that resolves below 1 becomes 1 rather than dividing by zero.
`requireAudioStage` becomes `requireStage(path, stage)` with the old name kept
as its automation wrapper.
The validator's binding-target check is no longer a regex over two families. It
reports ERR_INVALID_REFERENCE for an undeclared layer, system, or effect index
and ERR_UNSUPPORTED_TARGET for everything outside the four rows - per-object
properties, field strengths, emitter rates - which is the distinction trace 14
of 17.16 and trace 4 of 19.7 both check.
exhibits/minimal-visual.xzbt is a new fixture exercising the aligned surface:
two layers, a graphic system with system-scope automation, a repeater over a
component, a particle system reading a declared field, a spawned emitter with
its spawn container, two post-effects, and three bindings reaching three of the
four target families.
test/phase4-visual-contract.test.mjs adds 29 tests. `npm test` goes from 102 to
131 passing with zero failures; no existing test changed.
Co-Authored-By: Claude Opus 5 <[email protected]>
Claude-Session: https://claude.ai/code/session_0162Jb1J36judZNT8fHabGVt
LabyricornandClaude Opus 5
6587d3e442