# M16-GAP-00013 Status

status: done
task: Material data-block LOCAL_EXACT slice
updated: 2026-08-19 America/New_York

scope: Blender 5.2 Principled Material metadata and minimal shader graph: PBR values, IOR/transmission/coat, emission, alpha, two-node topology, one link and graph hash.

evidence:

- `tools/web/generated/M16-GAP-00013.py` generated a retained `WebGapMaterial` on a minimal triangle Mesh, with Principled and Material Output nodes.
- Desktop report reopened after save and matched exactly: base color `[0.2, 0.4, 0.8, 0.9]`, roughness 0.6, metallic 0.35, IOR 1.6, transmission 0.27, coat 0.64/0.12, emission `[0.05, 0.1, 0.2, 1]` at strength 3.5, two nodes and one link.
- WASM/Main opened the same fixture, matched all bounded material fields and shader graph topology, and produced a stable 64-character graph hash. WASM save/reopen matched the full material snapshot exactly.
- A truncated malformed Blend submitted to an already loaded Main was rejected and the original snapshot remained unchanged.
- `build_blender_5.2.0/bin/blender -b --factory-startup --python tools/web/generated/M16-GAP-00013.py -- tests/files/web/generated/M16-GAP-00013-datablock-Material.blend` exited 0.
- `npm --prefix web run test:generated-gap -- --task M16-GAP-00013` exited 0.
- `node tools/web/check-generated-gap.mjs --task M16-GAP-00013` exited 0.

artifacts: `tests/golden/M16-GAP-00013/manifest.json` contains SHA-256 for the parent manifest, fixture, generator, desktop/Web checkers, reader/protocol/runtime and both reports.

knownRisk: This closes one `datablock:Material` reader slice only. Material authoring commands, texture evaluation, unsupported node behavior and all other generated gaps remain separate tasks.

rollback: remove this task's fixture, checker, reports, manifest, status and context; restore `M16-GAP-00012` as the queue tail without editing its successful evidence.

nextTask: `M16-GAP-00014`