# Material Library And Targeted Drop Evaluation

Date: 2026-07-12
Branch: `codex/material-library-targeted-drop`
Implementation commit: `02247f0`

This record captures live acceptance for the docked Material Library and exact viewport
Material/Texture assignment workflow. The permanent user workflow lives in the
[material-system guide](../../material-system.md), and the implementation plan is
[material_library_and_targeted_drop_2026-07-12.plan.md](../../../../.cursor/plans/material_library_and_targeted_drop_2026-07-12.plan.md).

## Live Editor Evidence

The image below is a native Wayland capture from the debug editor. The assignment was previewed,
committed once, undone, previewed again, and canceled with Escape; the authored scene was not saved.

![Material Instance preview on the exact Ground surface with the docked Material Library and green target feedback](material-instance-surface-preview.png)

The Material Library resolves `surface_tint_instance` through its base Material and sparse
overrides. While the pointer is over the viewport, the green card names `Ground / Surface`, the
inspector reflects the transient material, and the scene-usage section identifies the exact actor
and surface. The preview does not push history or dirty the scene.

## Acceptance Results

| Area | Result | Evidence |
|------|--------|----------|
| Catalog workflow | Pass | Window menu entry, persisted bottom dock, search, Material/Instance/Used/Unused filters, grid/list views, resolved instance thumbnail, and details selection |
| Exact targeting | Pass | Primitive preview resolves one actor surface; automated coverage resolves one stable renderer slot and one stable brush face |
| Feedback | Pass | Neutral acquisition changes to green valid actor/surface feedback; invalid payload and read-only paths are covered by focused tests |
| Preview lifecycle | Pass | Live material and usage update without a history entry; Escape restores the exact prior material |
| Commit lifecycle | Pass | Release creates one typed history/operator entry; undo restores the prior surface |
| Startup hygiene | Pass | Relaunching the authored showcase after visibility-order correction produced no Bevy hierarchy warnings |
| Packaged acceptance | Deferred | Explicitly deferred by project-owner direction; no packaged result is claimed here |

## Automated Verification

| Command/suite | Result |
|---------------|--------|
| `cargo fmt --all -- --check` | Pass |
| `cargo check --workspace --all-targets` | Pass |
| `cargo clippy --workspace --all-targets -- -D warnings` | Pass |
| `cargo test --workspace` | Pass |
| Editor strict Clippy with `dev` and `hot-reload` features | Pass |
| `cargo validate-levels --project .` | 59 dependencies, 5 non-blocking findings, 0 blocking errors |
| `cargo bake-navigation --project . --check` | 1 deterministic artifact current |
| `git diff --check` | Pass |