polylabel 1.0.41

A Rust implementation of the Polylabel algorithm
Documentation 
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# Polylabel-rs
A Rust implementation of the [Polylabel](https://github.com/mapbox/polylabel) algorithm

The orange dot is the polygon centroid. The teal dot is the ideal label position. Red boxes show the search space.
[![GIF](output.gif)]()

You can generate this visualisation yourself by cloning this repo, switching to the [`visualise`](https://github.com/urschrei/polylabel-rs/tree/visualise) branch, and opening the [`visualise.ipynb`](https://github.com/urschrei/polylabel-rs/blob/visualise/visualise.ipynb) Jupyter notebook, then stepping through the cells. You can also easily visualise a Polygon of your own using the notebook.

# How to Use
```rust
extern crate polylabel;
use polylabel::polylabel;

extern crate geo;
use geo::{Point, LineString, Polygon};

let coords = vec![
    (0.0, 0.0),
    (4.0, 0.0),
    (4.0, 1.0),
    (1.0, 1.0),
    (1.0, 4.0),
    (0.0, 4.0),
    (0.0, 0.0)
];
let ls = LineString(coords.iter().map(|e| Point::new(e.0, e.1)).collect());
let poly = Polygon::new(ls, vec![]);
let label_pos = polylabel(&poly, &0.10);
// Point(0.5625, 0.5625)
```

## Documentation
https://docs.rs/polylabel

# FFI
Call `polylabel_ffi` with the following three mandatory arguments:
- [`Array`](https://docs.rs/polylabel/1.0.3/polylabel/struct.Array.html) (a struct with two fields:
    - `data`: a void pointer to an array of two-element `c_double`s, the exterior Polygon shell)
    - `len`: the length of the `data` array, a `size_t`
- [`WrapperArray`](https://docs.rs/polylabel/1.0.3/polylabel/struct.WrapperArray.html) (a struct with two fields):
    - `data`: a void pointer to an array of `Array`s, each entry representing and interior Polygon ring. Empty if there are no rings.
    - `len`: the length of the `data` array, a `size_t`. 0 if it's empty.
- `tolerance`, a `c_double`

The function returns a [struct](https://docs.rs/polylabel/1.0.3/polylabel/struct.Position.html) with two `c_double` fields:
- `x_pos`
- `y_pos`

A Python example is available in [`ffi.py`](ffi.py)

# Binaries
Binary libs for:
- `x86_64` *nix (built using `manylinux1`, thus easy to include in Python 2.7 / 3.5 / 3.6 wheels) and OS X
- `i686` and `x86_64` Windows

are available in [releases](https://github.com/urschrei/polylabel-rs/releases).

# License
[MIT](license.txt)