isosurface-generator

A JS generator function that returns a mesh describing an isosuface given a density and level. Since it's a generator function, you can perform this expensive calculation in a way that allows you to keep your UI responsive.

DEMO

Install

npm install isosurface-generator

Example

const isosurfaceGenerator = require('isosurface-generator');
const ndarray = require('ndarray');

const size = 8;

const density = ndarray(new Float32Array(size*size*size), [size, size, size]);

for (let i = 0; i < 1000; i++) {
  density.set(
    Math.floor(Math.random() * size),
    Math.floor(Math.random() * size),
    Math.floor(Math.random() * size),
    Math.random()
  );
}

let mesh;

for (let data of isosurfaceGenerator(density, 0.5)) {
  mesh = {
    positions: data.positions,
    cells: data.cells,
  };
  console.log('Fraction complete:', data.fraction);
  // await display update
}

API

require('isosurface-generator')(density, level)

Parameters

density is an ndarray (or an object that implements ndarray's .get method and .shape attribute)

level is the density value for which we're generating an isosurface

Return value

A generator function that will provide a mesh describing the isosurface mesh and the fraction complete:

const generator = isosurfaceGenerator(density, 0.5);

generator.next();

// Returns {
//   value: {
//     positions: [[1,2,3], [4,5,6], ...],
//     cells: [[1,2,3], [4,5,6], ...],
//     fraction: 0.009
//   },
//   done: false
// }

Resources

• https://0fps.net/2012/07/12/smooth-voxel-terrain-part-2