support-fins/prototype/ui-smoke

UI smoke gate: "did the page change?"

The Deno suite and the sweep only cover the engine (fins.js, prop.js, …). Nothing else exercises web/app.js and web/ui/. This covers them: it drives the real page in headless Chrome through a fixed script of 85 steps and records everything visible after each step, then diffs that against a base build.

prototype/ui-smoke/vs-base.sh                  # vs origin/main, models cone + lbracket (~1.5 min)
prototype/ui-smoke/vs-base.sh <sha>            # vs any commit that has window.__sf.camera
MODELS="cone tshape" prototype/ui-smoke/vs-base.sh
KEEP=/some/dir prototype/ui-smoke/vs-base.sh   # keep the JSON dumps

# one run, to look at or to diff by hand
deno run -A prototype/ui-smoke/ui-smoke.js --model cone --out run.json
deno run -A prototype/ui-smoke/compare.js base.json run.json

The script: load → rotate X, Y → fins on → remove the nearest fin (hover, click, Esc, restore, ⌘Z, redo) → PETG → pad Sure hold / Custom / gap / Auto → tines off/on → sway → diamond cutouts → coverage 80 → Draw: a wall across the overhang, then Esc, undo, clear, and their undos → Auto with the drawn wall → "+ Add" on/off → strength arrow up / right / suggest / clear → layer view → lay a face flat + undo → Suggest orientation, pick #2, collapse → reset → fins off/on → overhang 55° → custom volume → 6× undo → arm removal and import a second model → two-body STEP: picker, tick both, merge → two-object 3MF: picker, Cancel, import a copy, Load.

Each step records: every element with an id (text, hidden, disabled, class, value, select options, the (i) tooltip); the part's quaternion; triangle count + checksum of the fins, pad and drawn walls; the export geometry; every visible mesh/line (type, colour, vertex count) and material opacity; the canvas cursor; and every console error or warning. s-time and fps are skipped because they vary run to run. Two runs of the same build are identical, so any line compare.js prints is a real change.

What it's for: refactors that must not change behaviour (issue #22). For a deliberate UI change it lists every place the change shows up, which is useful for checking that nothing else moved.

Needs: Deno and a local Chrome (CHROME=/path/to/chrome to override the macOS default). It serves web/ and prototype/stress/models/ itself, so it needs no dev server and none of the gitignored dev-models. It runs one Chrome at a time, because two in parallel stalled the GPU process.

Not covered: gizmo ring drags, drag-and-drop (imports go through the file input), and export downloads (it checks the export geometry, not the file bytes). Check those by hand when a change touches them.