orx-triangulation

Delaunay triangulation and Voronoi diagrams.

The functionality comes from a Javascript port of the following libraries:

delaunator (external)
d3-delaunay (the port is included in this package)

Usage

DelaunayTriangulation

The entry point is the DelaunayTriangulation class.

    val points: List<Vector2>
    val delaunay = DelaunayTriangulation(points)

    // or
    
    val delaunay = points.delaunayTriangulation()

This is how you retrieve the triangulation results:

val triangles: List<Triangle> = delaunay.triangles()
val halfedges: List<ShapeContour> = delaunay.halfedges()
val hull: ShapeContour = delaunay.hull()

Voronoi

The bounds specify where the Voronoi diagram will be clipped.

val bounds: Rectangle

val delaunay = points.delaunayTriangulation()
val voronoi = delaunay.voronoiDiagram(bounds)
// or
val voronoi = points.voronoiDiagram(bounds)

See To Infinity and Back Again for an interactive explanation of Voronoi cell clipping.

This is how you retrieve th results:

val cells: List<ShapeContour> = voronoi.cellPolygons()
val cell: ShapeContour = voronoi.cellPolygon(int) // index
val circumcenters: List<Vector2> = voronoi.circumcenters

// Returns true if the cell with the specified index i contains the specified vector
val containsVector = voronoi.contains(int, Vector2)

Authors

Ricardo Matias / @ricardomatias Edwin Jakobs / @edwinRNDR

Demos

DemoDelaunay01

This method sets up a graphical application using the OPENRNDR framework to visually demonstrate Delaunay triangulation on a set of points scattered along a circle with Poisson disk sampling.

The application features the following:

A central circle with a defined radius.
Points generated within the circle using a scatter algorithm that maintains specific spacing and avoids clustering.
Delaunay triangulation computed from the combined point set.
Rendering of triangles that are part of the Delaunay triangulation.
Visual styling with dynamic color shading for better clarity of layers and triangle order.

This method demonstrates concepts of computational geometry and procedural rendering.

source code

DemoDelaunay02

source code

DemoVoronoi01

This program generates a Voronoi diagram within a defined circular area and visualizes it.

The program performs the following:

Defines a circular area and a rectangular bounding frame within the canvas.
Uses Poisson Disk Sampling to generate points within the circular area.
Computes the Delaunay triangulation for the generated points, including equidistant points on the circle boundary.
Derives the Voronoi diagram using the Delaunay triangulation and the bounding frame.
Extracts the cell polygons of the Voronoi diagram.
Renders the Voronoi cell polygons on the canvas, with a pink stroke on a black background.