@draco-rust/ply

Reads and writes PLY in WebAssembly: meshes and point clouds, in ASCII and binary. Every property is kept: the ones it has no attribute for come back by name, so a Gaussian splat arrives with its scales, rotations, opacity and spherical harmonics. It is part of draco-rust and drives the converter.

~89 KiB gzip.

Usage

import init, { read_ply, write_ply } from "@draco-rust/ply";

await init();
const result = read_ply(plyBytes);
if (!result.success) throw new Error(result.error);
const { positions, indices, normals, colors, extras } = result.meshes[0];
// indices is empty for a point cloud; extras holds the other properties

write_ply(mesh, { format }) writes one back, as a Uint8Array in bytes: binary little-endian by default, or format: "binary_big_endian", or format: "ascii", which also comes back as text.

On workers

A large file blocks the calling thread while it is read or written. @draco-rust/ply/pool runs the same functions on workers:

import { createPool } from "@draco-rust/ply/pool";

const pool = createPool({ workers: 2 }); // default: cores - 1, at most 4
const result = await pool.read(bytes); // what read_ply returns
const written = await pool.write(mesh, {}); // what write_ply returns
pool.dispose();

The workers start as work arrives, and the wasm is compiled once for all of them. Inputs are copied to the worker, or handed over with { transfer: true }; { signal } takes an AbortSignal, which rejects the promise at once. A task a worker has started still runs to its end and its result is dropped. With workers: 0, or where there are no workers, the pool runs on the calling thread. It works on Web Workers, Node's worker threads (Node 20.16 and later) and from a CDN, as the decoder's does.

For loading from a CDN or in Node, see the decoder's README; the same init options apply, with @draco-rust/ply/index_bg.wasm as the file.

Licensed under Apache-2.0.

This build

@draco-rust/[email protected] was built from draco-rust commit 4b72cfc8, with draco-core 2.3.2, draco-io 0.6.0, draco-gltf 0.7.0.