anvil-reduce 0.2.4

Volume-based mesh proxy generator. Voxelize, marching-cubes, smooth, remesh. Fast, watertight, hands-off.

anvil-reduce

Watertight mesh proxy generator: exact narrow-band distance field, marching cubes, smooth, remesh, exact surface projection. Fast, verifiable, hands-off. Native Rust core, Python bindings via PyO3.

Install

pip install anvil-reduce

Inside DCCs:

mayapy -m pip install anvil-reduce          # Maya
hython -m pip install anvil-reduce          # Houdini
# Blender: install into the addon's bundled Python or vendor the wheel

Quick start

One-shot file pipeline (the path most pipeline TDs want):

from anvil_reduce import proxy_from_path

result = proxy_from_path(
    "hero.usd",
    "hero_proxy.usd",            # .usd/.usdc = binary, .usda = ASCII
    quality="balanced",          # "fast" | "balanced" | "high"
    transfer_normals=True,
)
print(f"{result['input_faces']} -> {result['output_faces']} in "
      f"{result['wall_seconds']:.2f}s")

NumPy-driven workflow:

import numpy as np
from anvil_reduce import Mesh, generate_proxy

mesh = Mesh.from_numpy(positions, indices)   # (N,3) f64, (M,3) u32
proxy = generate_proxy(mesh, quality="balanced", target_faces=20_000)
positions, indices = proxy.positions(), proxy.indices()

Functions

Function	What it does
proxy_from_path(in, out, **kw)	File-to-file pipeline, returns a stats dict
generate_proxy(mesh, **kw)	Proxy for an in-memory Mesh
generate_lod_chain(mesh, levels=4, **kw)	List of meshes: the original, then each level at half resolution
load(path) / save(mesh, path)	Mesh I/O: .obj, .glb, .gltf, .usd, .usda, .usdc
Mesh.from_numpy(positions, indices)	Build a mesh from numpy arrays

USD output is a Mesh prim with purpose = "proxy" and an authored extent, so usdview and DCCs bind it as proxy geometry directly. USD input is sniffed: crate (binary) and ASCII layers both load. No composition — flatten referenced assets with usdcat --flatten first.

Quality presets

Preset	voxel_res	smooth	remesh
fast	64	3	0
balanced	128	5	3
high	256	5	5

Override individual knobs by passing them explicitly. target_faces hits an output face budget (resolution and remesh edge length are derived from it). offset is the standoff from the input surface in voxel cells (0 = surface-exact, default 0.1, larger = looser hull); close seals gaps in open meshes; project caps the final exact projection onto the offset surface.

The output is closed, outward-wound, and free of degenerate triangles; verify with the CLI's check command.

See https://github.com/voidreamer/anvil-reduce for the full project.