@rgsoft/voronoi

Voronoi

Voronoi tessellation lib

Installation

npm install @rgsoft/voronoi

Usage

Triangulation

The triangulate function generates a Delaunay triangulation, returning an array of Triangle instances.

const { triangulate } = require('@rgsoft/voronoi');

const triangulation = triangulate(points, config);

The points parameter is an array of Vector (@rgsoft/math package), containing the points for the triangles vertex. The config may have the following properties:

• rectBox - an array of four Vector instances used as initial box for the triangulation
• excludeRectVertex - a boolean value that indicates whether the triangles generated with the initial box should be removed from the resulting triangulation (default false)

As a full example:

const { triangulate } = require('@rgsoft/voronoi');

const points = [ new Vector(0.5 , 0.5) ];
const config = {
    rectBox: [
        new Vector(0, 1),
        new Vector(1, 1),
        new Vector(1, 0),
        new Vector(0, 0),
    ]
}

const triangulation = triangulate(points, config);

The rectBox points array is expected to be ordered in this fashion:

1. TOP-LEFT
2. TOP-RIGHT
3. BOTTOM-RIGHT
4. BOTTOM-LEFT

If rectBox is not provided, the box will be inferred using the getRectBox function.

RectBox

The getRectBox receives an array of Vector instances, and returns another array with the four points of the rectangular box that contains these points. For example, if the provided points are A, B, C, and D (in any order), the resulting box array would be [E, F, G, H] (in that order).

Tessellation

The tessellate function draws the Voronoi tessellation on a HTMLCanvasElement. It expects a CanvasRenderingContext2d and a triangulation (array of Triangle).

const { triangulate } = require('@rgsoft/voronoi');

const points = [ new Vector(0.5 , 0.5) ];
const config = {
    rectBox: [
        new Vector(0, 1),
        new Vector(1, 1),
        new Vector(1, 0),
        new Vector(0, 0),
    ]
}

const triangulation = triangulate(points, config);
const canvasElement = document.getElementById('canvas1');
const context = canvasElement.getContext('2d');

tessellate(context, triangulation);