I needed a delaunay library for my own, but didn’t found any that was meeting my requirment, so I ended up porting as3delaunay library to c#. I also added a Lloyd relaxation function to it.
So I though that I could post it. If anyone need it, go ahead it’s completly free.
Download link:csDelaunay Library
It’s pretty straighforward to use, but here is an exemple:
using UnityEngine;
using System.Collections.Generic;
using csDelaunay;
public class VoronoiDiagram : MonoBehaviour {
// The number of polygons/sites we want
public int polygonNumber = 200;
// This is where we will store the resulting data
private Dictionary<Vector2f, Site> sites;
private List<Edge> edges;
void Start() {
// Create your sites (lets call that the center of your polygons)
List<Vector2f> points = CreateRandomPoint();
// Create the bounds of the voronoi diagram
// Use Rectf instead of Rect; it's a struct just like Rect and does pretty much the same,
// but like that it allows you to run the delaunay library outside of unity (which mean also in another tread)
Rectf bounds = new Rectf(0,0,512,512);
// There is a two ways you can create the voronoi diagram: with or without the lloyd relaxation
// Here I used it with 2 iterations of the lloyd relaxation
Voronoi voronoi = new Voronoi(points,bounds,5);
// But you could also create it without lloyd relaxtion and call that function later if you want
//Voronoi voronoi = new Voronoi(points,bounds);
//voronoi.LloydRelaxation(5);
// Now retreive the edges from it, and the new sites position if you used lloyd relaxtion
sites = voronoi.SitesIndexedByLocation;
edges = voronoi.Edges;
DisplayVoronoiDiagram();
}
private List<Vector2f> CreateRandomPoint() {
// Use Vector2f, instead of Vector2
// Vector2f is pretty much the same than Vector2, but like you could run Voronoi in another thread
List<Vector2f> points = new List<Vector2f>();
for (int i = 0; i < polygonNumber; i++) {
points.Add(new Vector2f(Random.Range(0,512), Random.Range(0,512)));
}
return points;
}
// Here is a very simple way to display the result using a simple bresenham line algorithm
// Just attach this script to a quad
private void DisplayVoronoiDiagram() {
Texture2D tx = new Texture2D(512,512);
foreach (KeyValuePair<Vector2f,Site> kv in sites) {
tx.SetPixel((int)kv.Key.x, (int)kv.Key.y, Color.red);
}
foreach (Edge edge in edges) {
// if the edge doesn't have clippedEnds, if was not within the bounds, dont draw it
if (edge.ClippedEnds == null) continue;
DrawLine(edge.ClippedEnds[LR.LEFT], edge.ClippedEnds[LR.RIGHT], tx, Color.black);
}
tx.Apply();
this.renderer.material.mainTexture = tx;
}
// Bresenham line algorithm
private void DrawLine(Vector2f p0, Vector2f p1, Texture2D tx, Color c, int offset = 0) {
int x0 = (int)p0.x;
int y0 = (int)p0.y;
int x1 = (int)p1.x;
int y1 = (int)p1.y;
int dx = Mathf.Abs(x1-x0);
int dy = Mathf.Abs(y1-y0);
int sx = x0 < x1 ? 1 : -1;
int sy = y0 < y1 ? 1 : -1;
int err = dx-dy;
while (true) {
tx.SetPixel(x0+offset,y0+offset,c);
if (x0 == x1 && y0 == y1) break;
int e2 = 2*err;
if (e2 > -dy) {
err -= dy;
x0 += sx;
}
if (e2 < dx) {
err += dx;
y0 += sy;
}
}
}
}
More info on Voronoi Diagram: Voronoi diagram wiki
And lloyd relaxation: Lloyd’s_algorithm wiki
and another time the library download link: csDelaunay Library
