Johann J Cardenas

Gear3D — third-party asset credits

Every file in this directory, its license, and what was done to it.

Rubber004 — tire surface micro-detail


Files	`rubber004_normal.jpg`, `rubber004_rough.jpg`
Source	https://ambientcg.com/view?id=Rubber004
Provider	ambientCG (Lennart Demes)
License	CC0 1.0 Universal (public domain dedication)
License verified	https://ambientcg.com/license — “licensed under the Creative Commons CC0 1.0 Universal License”
Retrieved	2026-08-03
Tile size	75 × 75 mm (the provider’s stated physical scale)

CC0 requires no attribution. This record exists anyway, because an engineering tool should be able to account for every pixel it ships.

What was changed

Downloaded as the 1K-JPG set (8.4 MB). From it, only the NormalGL and Roughness maps were kept, resized to 512 × 512 and re-encoded as progressive JPEG at quality 88 — 114 KB total.

Deliberately not used:

Color — Gear3D drives base color from its own material spec so the tint and brightness controls stay meaningful, and so a scanned photograph’s baked-in lighting can never contaminate a figure.
Displacement — tread relief is real geometry (src/geometry/tire.js).
Metalness — a per-material constant here, not a map.

512 px is not a compromise: these are seamless micro-detail maps tiled dozens of times around a tire’s circumference, so resolution beyond the tile’s own physical scale buys nothing visible and costs weight on a GitHub Pages site.

How it is applied

Tiling is derived from real physical dimensions, not guessed. For an 11R22.5 the circumference is π × 1054 mm = 3311 mm, which is 3311 / 75 = 44.1 tiles; the tire mesh’s own UVs already repeat 11 times, so the texture repeat is 44.1 / 11 = 4.01. Rubber grain is therefore the same physical size on a motorcycle tire as on an aircraft tire, as it is in life.

Evaluated and rejected

Recording these matters as much as recording what shipped: the next person to ask “why isn’t there a metal texture?” deserves the answer.

Metal012 — rejected

https://ambientcg.com/view?id=Metal012, also CC0.

Two independent reasons:

Its normal map is almost perfectly flat (2 KB at 512 px after compression) — a smooth metal, contributing no visible machining detail.
Its roughness map dropped the rims and axle beams to a wet, plastic gloss that was plainly worse than the tuned values.

The underlying point is physical: machined metal is characterized by what it reflects, and the studio environment map (src/scene/environment.js) already supplies that. Rubber gains from measured micro-detail because rubber genuinely is micro-detailed.

Poly Haven CC0 meshes — rejected

https://polyhaven.com/license confirms CC0 with redistribution explicitly permitted, so licensing was not the obstacle. Dimensions were checked against the 1.6× distortion cap in ASSETS.md §4:

Mesh	Actual size	Scaled to 11R22.5	Verdict
`old_tyre`	600 × 165 mm	1.757×	exceeds the cap
`rusted_wheel_rim_01`	403 × 154 mm	2.615×	exceeds the cap

Both are car parts, not truck parts, and both are tagged by their authors as trash / scrapyard / junkyard / rusted. They do fit the light FHWA classes within the cap (old_tyre → P225/60R16 is 1.364×), but a rusted scrapyard car tire is an appearance downgrade for a pavement engineering figure, on precisely the vehicle classes that matter least for pavement loading.

The procedural tire is dimensionally exact for any designation in the library, including sizes nobody has modeled. It remains the reference implementation.

No CC0 truck wheel, truck tire or aircraft landing gear mesh was found. Poly Haven’s 521-model library is props, tools and furniture; the search covered every asset whose name, tags or categories matched wheel, tire, truck, vehicle, aircraft, axle or industrial.

If you want to add an asset

Follow ASSETS.md. Record the source URL, the license identifier and the author in the manifest entry. If those three cannot be stated, the asset does not go in.

This site is open source. Improve this page.