Built-in primitive meshes

The .mesh assets in this folder are the engine's built-in primitive geometry — the rough-blockout shapes every world can reference by bare name ({ model = "cube" }) without authoring or importing anything.

Each <name>.mesh is a loader-folder asset whose primary content is the engine-native ZMSH geometry binary at <name>.mesh/data.zmsh. The folder carries a .metadata sidecar tagging it primitive and builtin, and a committed .meta sidecar pinning its stable guid (authored content references the guid, never the name).

Each is centred on its local origin, so an entity's scale reads directly as the size the mesh covers in the world.

Asset	Shape	Extent (x, y, z)
cube	unit cube	1 x 1 x 1
sphere	UV sphere	1 x 1 x 1
plane	flat quad (XZ)	1 x 0 x 1
cylinder	capped cylinder	1 x 1 x 1
cone	capped cone	1 x 1 x 1
capsule	rounded-end capsule	0.5 x 1 x 0.5
rounded_box	box with rounded edges and corners	1 x 1 x 1
torus	ring	1 x 0.3 x 1
octahedron	8-faced diamond	1 x 1 x 1
ground_hex	hexagonal ground tile	1.732 x 0.1 x 2
ground_quad	large ground quad	1 x 0.1 x 1
shader_ball	sphere on a pedestal, a quarter of its upper half cut away — what a shader's preview is painted on	0.933 x 1 x 0.933

meshRef:load():getBounds() reads the same numbers back. guides { path = "types/mesh" } carries the winding, index-base, UV and axis conventions the geometry is authored against.

Publishing the geometry blobs

These meshes resolve their data.zmsh bytes by sha-256 (content addressing) on targets that don't have the repo's src/lua/lib on disk — WASM (the browser build) and release native binaries run outside the repo. That requires each blob to exist in ZeroMind's content store. Publish them with:

node scripts/publish_builtin_blobs.mjs        # upload (skips blobs already present)
node scripts/publish_builtin_blobs.mjs --dry-run

The upload set is derived from the build's BUILTIN_LIB_BINARY_LEAVES, so build the engine once (cargo build --bin native) before publishing. The script is idempotent: a blob whose sha already exists in the store is left untouched.

Primitives are for blockout, not finished work — author or import real geometry for anything shipping.