Tavern Stool

A showcase piece, not an example. A procedural tavern stool: a lathed round seat, turned splayed legs, tenoned stretchers at two heights, and iron ferrules on level treads. Then the shipped pipeline: unique-cell UVs, a Cycles high-to-low normal bake, an LOD chain, a convex collider and a Unity glTF export.

Legs are one loft per leg, not stacked cones. Each foot is an iron ferrule sleeve on the leg's own axis, its inner wall a named grip (1.2 mm) inside the leg. The sleeve's raked bottom rim is buried in a level iron tread, and the leg ends inside the sleeve, above the tread. The first build ended every leg 3 mm above a vertical ring on the floor, with a 1 mm air gap around the foot. The front-back and side stretchers sit at different heights, so their tenons do not meet inside the leg. Each member has its own wood tone and grain. The seat is dished 14 mm at the centre for sitting, from the same lathe ring count as the old 6 mm dish, so the triangle count did not move. The dish floor stays 8 mm above the leg tenons wherever a leg enters from below.

The hero stands the stool level and turns it about Z only. An earlier still rolled it 6° about X to show the seat, which sank one pair of treads into the floor and lifted the other; the camera now sits higher instead. A pewter tankard stands in the dish as render-only dressing. It is not part of the asset: no budget, no export, and the asset sheet renders the stool without it.

It asserts budget conformance of the generated result. It does not witness an API contract. "It rendered without error" is not a check.

Composes skills mesh-editing-and-bmesh, bake-high-to-low, depsgraph-and-evaluated-data, engine-export-presets, and snippets bake_normal_high_to_low.py, setup_bake_target_image.py, lod_chain.py / decimate_to_budget.py, convex_hull_collider.py, export_preset_unity.py (helpers copied, not imported as a package).

Budgets#

Declared as named constants. Every gate recomputes its value from the mesh, materials, UVs, evaluated LOD, collider or export file.

Base triangles rose from 2528 to 3040 in the second quality pass, and the band moved from 2300–3200 to 2750–3350. Each foot gained a tread, and the sleeves are walled on both ends. The bake went from 256 px to 1024 px, and its cage extrusion from 60 mm to 10 mm. See the bake texel budget below.

DECIMATE COLLAPSE triangle counts are not identical across series. The gate is a ratio band, not an exact count. Bake pixels are stochastic; the gate is has_data plus operator FINISHED, not byte-identity. Construction is closed-form and member tones are seeded, so repeated runs on one binary print identical measurements. Export byte counts may differ by a few bytes across series.

Hygiene#

Recomputed from the generated mesh, not asserted about the script.

Joint fit, feet and bake#

At 256 px the bake gave each of the 1,744 UV cells about 6 px. The hero then sampled the neighbouring cells' normals across cell borders, which showed as dark slivers on the legs above the ferrules.

Falsifiers#

Each violates one named budget. All were run on 4.5.11, 5.1.2 and 5.2.1 and returned the same code on each.

--pipe-ferrule keeps the treads, so the triangle band and the envelope cannot steal its failure. --sink-legs keeps the leg inside its sleeve, so the grip still passes.

Run#

blender --background --python tavern_stool.py --
blender --background --python tavern_stool.py -- --skip-decimate
blender --background --python tavern_stool.py -- --stray-vert
blender --background --python tavern_stool.py -- --lift-z
blender --background --python tavern_stool.py -- --short-legs
blender --background --python tavern_stool.py -- --float-stretchers
blender --background --python tavern_stool.py -- --pipe-ferrule
blender --background --python tavern_stool.py -- --sink-legs
blender --background --python tavern_stool.py -- --low-bake
blender --background --python tavern_stool.py -- --output stool.png

Smoke passes no flags.

Exit codes#

File-local. 9 is a valid check code. 10 is reserved for gallery_framing.check_framing on the --output path. 15–19 are the hygiene and joint-fit family. 20 and 21 are this piece's own.