greedy-mesher

1.0.3 verified Fri May 01 auth: no javascript

A flexible system for generating greedy meshes of ndarrays, version 1.0.3. It compiles a custom mesher function based on provided options like order, skip, merge, and append closures. Unlike hardcoded greedy meshing algorithms, this package allows full control over traversal order and voxel merging logic. The library is optimized for ndarray data structures and is commonly used in voxel-based graphics and geometry processing. The release cadence is archival; no updates since 2013. Key differentiators: runtime code generation, customizable merging criteria, and support for arbitrary dimensions.

Common errors

error TypeError: Cannot read properties of undefined (reading 'length') ↓

cause Order array not provided or has wrong length.

fix

Provide an order array with length equal to the number of dimensions of the input ndarray.

error ReferenceError: append is not defined ↓

cause The 'append' option is required but not provided in options.

fix

Add an 'append' function to the options object.

error TypeError: array.get is not a function ↓

cause Using an ndarray without setting useGetter: true.

fix

Set useGetter: true in the options when passing an ndarray.

Warnings

gotcha The order array must have length equal to the number of dimensions of the input ndarray; otherwise, the generated code will be incorrect or crash. ↓

fix Ensure order.length equals ndarray dimension.

gotcha The append closure receives coordinates in the order specified by 'order', not the original axis order. ↓

fix Design append to match the permutation given in order.

gotcha If 'useGetter' is not set, the mesher assumes the array is a native typed array; for ndarrays, set useGetter: true or the generated code will fail. ↓

fix Set useGetter: true when passing an ndarray.

breaking No breaking changes known; minor version bumps are unlikely. ↓

fix N/A

Install

npm install greedy-mesher

yarn add greedy-mesher

pnpm add greedy-mesher

Imports

default

wrong

import compileMesher from 'greedy-mesher'

correct

const compileMesher = require('greedy-mesher')

The library is CommonJS-only; no ESM export. Use require().

Mesher options
wrong
```
const mesher = require('greedy-mesher')({ order: [0,1] })
```
correct
```
const mesher = compileMesher({ order: [1,0], extraArgs: 0, ... })
```
The order array dimensionally matches the ndarray's shape; must have length equal to number of dimensions. Extra args default to 0 if not specified.
Mesher call
wrong
```
const result = mesher(array)
```
correct
```
mesher(array, arg1, arg2, ...)
```
The mesher function appends to an array passed as the last argument? Actually, signature: let result = mesher(array, arg1, arg2, ...). The returned result is the last argument's value? Final arg is the results array. Example: mesher(array, result).

Quickstart

Creates a custom mesher for a 2D ndarray, merging adjacent equal voxels (excluding 0) and appending rectangles.

const compileMesher = require('greedy-mesher');
const ndarrayPack = require('ndarray-pack');

const mesher = compileMesher({
  extraArgs: 1,
  order: [1, 0],
  append: function(lo_x, lo_y, hi_x, hi_y, val, result) {
    result.push([[lo_x, lo_y], [hi_x, hi_y]]);
  }
});

const input = ndarrayPack([
  [0, 2, 0, 0],
  [0, 1, 1, 0],
  [0, 1, 1, 0],
  [0, 0, 0, 0]
]);

const result = [];
mesher(input, result);
console.log(result);
// Output:
// [ [ [ 1, 0 ], [ 2, 1 ] ], [ [ 1, 1 ], [ 3, 3 ] ] ]