README.md

# delaunator-cpp

A really fast C++ library for
[Delaunay triangulation](https://en.wikipedia.org/wiki/Delaunay_triangulation) of 2D points.

delaunator-cpp is a C++ port from https://github.com/mapbox/delaunator a JavaScript implementation of very fast 2D Delaunay algorithm.

[![Build Status](https://travis-ci.org/delfrrr/delaunator-cpp.svg?branch=master)](https://travis-ci.org/delfrrr/delaunator-cpp)
[![badge](https://mapbox.s3.amazonaws.com/cpp-assets/hpp-skel-badge_blue.svg)](https://github.com/mapbox/hpp-skel)

## Features

* Probably the fastest C++ open source 2D Delaunay implementation
* Roughly 3 times faster then JS version.
* Example showing triangulation of GeoJson points

## Usage

```CPP
#include <delaunator.hpp>
#include <cstdio>

//...
int main(int, char* argv[]) {
    //...
    std::vector<double> coords = {/* x0, y0, x1, y1, ... */};

    //triangulation happens here
    //note moving points to constructor
    delaunator::Delaunator delaunator(coords);

    for(std::size_t i = 0; i < delaunator.triangles.size(); i+=3) {
        printf(
            "Triangle points: [[%f, %f], [%f, %f], [%f, %f]]\n",
            delaunator.coords[2 * delaunator.triangles[i]],         //tx0
            delaunator.coords[2 * delaunator.triangles[i] + 1],     //ty0
            delaunator.coords[2 * delaunator.triangles[i + 1]],     //tx1
            delaunator.coords[2 * delaunator.triangles[i + 1] + 1], //ty1
            delaunator.coords[2 * delaunator.triangles[i + 2]],     //tx2
            delaunator.coords[2 * delaunator.triangles[i + 2] + 1], //ty2
        )
    }
}
```

For full example see `examples/triangulate/main.cpp`

## TODO

* Benchmarks
* Unit tests