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pub struct Polygon<T: CoordNum> { /* private fields */ }
Expand description

A bounded two-dimensional area.

A Polygon’s outer boundary (exterior ring) is represented by a LineString. It may contain zero or more holes (interior rings), also represented by LineStrings.

A Polygon can be created with the Polygon::new constructor or the polygon! macro.

Semantics

The boundary of the polygon is the union of the boundaries of the exterior and interiors. The interior is all the points inside the polygon (not on the boundary).

The Polygon structure guarantees that all exterior and interior rings will be closed, such that the first and last Coordinate of each ring has the same value.

Validity

  • The exterior and interior rings must be valid LinearRings (see LineString).

  • No two rings in the boundary may cross, and may intersect at a Point only as a tangent. In other words, the rings must be distinct, and for every pair of common points in two of the rings, there must be a neighborhood (a topological open set) around one that does not contain the other point.

  • The closure of the interior of the Polygon must equal the Polygon itself. For instance, the exterior may not contain a spike.

  • The interior of the polygon must be a connected point-set. That is, any two distinct points in the interior must admit a curve between these two that lies in the interior.

Refer to section 6.1.11.1 of the OGC-SFA for a formal definition of validity. Besides the closed LineString guarantee, the Polygon structure does not enforce validity at this time. For example, it is possible to construct a Polygon that has:

  • fewer than 3 coordinates per LineString ring
  • interior rings that intersect other interior rings
  • interior rings that extend beyond the exterior ring

LineString closing operation

Some APIs on Polygon result in a closing operation on a LineString. The operation is as follows:

If a LineString’s first and last Coordinate have different values, a new Coordinate will be appended to the LineString with a value equal to the first Coordinate.

Implementations

Create a new Polygon with the provided exterior LineString ring and interior LineString rings.

Upon calling new, the exterior and interior LineString rings will be closed.

Examples

Creating a Polygon with no interior rings:

use geo_types::{LineString, Polygon};

let polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![],
);

Creating a Polygon with an interior ring:

use geo_types::{LineString, Polygon};

let polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![LineString::from(vec![
        (0.1, 0.1),
        (0.9, 0.9),
        (0.9, 0.1),
        (0.1, 0.1),
    ])],
);

If the first and last Coordinates of the exterior or interior LineStrings no longer match, those LineStrings will be closed:

use geo_types::{coord, LineString, Polygon};

let mut polygon = Polygon::new(LineString::from(vec![(0., 0.), (1., 1.), (1., 0.)]), vec![]);

assert_eq!(
    polygon.exterior(),
    &LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.),])
);

Consume the Polygon, returning the exterior LineString ring and a vector of the interior LineString rings.

Examples
use geo_types::{LineString, Polygon};

let mut polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![LineString::from(vec![
        (0.1, 0.1),
        (0.9, 0.9),
        (0.9, 0.1),
        (0.1, 0.1),
    ])],
);

let (exterior, interiors) = polygon.into_inner();

assert_eq!(
    exterior,
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.),])
);

assert_eq!(
    interiors,
    vec![LineString::from(vec![
        (0.1, 0.1),
        (0.9, 0.9),
        (0.9, 0.1),
        (0.1, 0.1),
    ])]
);

Return a reference to the exterior LineString ring.

Examples
use geo_types::{LineString, Polygon};

let exterior = LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]);

let polygon = Polygon::new(exterior.clone(), vec![]);

assert_eq!(polygon.exterior(), &exterior);

Execute the provided closure f, which is provided with a mutable reference to the exterior LineString ring.

After the closure executes, the exterior LineString will be closed.

Examples
use geo_types::{coord, LineString, Polygon};

let mut polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![],
);

polygon.exterior_mut(|exterior| {
    exterior.0[1] = coord! { x: 1., y: 2. };
});

assert_eq!(
    polygon.exterior(),
    &LineString::from(vec![(0., 0.), (1., 2.), (1., 0.), (0., 0.),])
);

If the first and last Coordinates of the exterior LineString no longer match, the LineString will be closed:

use geo_types::{coord, LineString, Polygon};

let mut polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![],
);

polygon.exterior_mut(|exterior| {
    exterior.0[0] = coord! { x: 0., y: 1. };
});

assert_eq!(
    polygon.exterior(),
    &LineString::from(vec![(0., 1.), (1., 1.), (1., 0.), (0., 0.), (0., 1.),])
);

Return a slice of the interior LineString rings.

Examples
use geo_types::{coord, LineString, Polygon};

let interiors = vec![LineString::from(vec![
    (0.1, 0.1),
    (0.9, 0.9),
    (0.9, 0.1),
    (0.1, 0.1),
])];

let polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    interiors.clone(),
);

assert_eq!(interiors, polygon.interiors());

Execute the provided closure f, which is provided with a mutable reference to the interior LineString rings.

After the closure executes, each of the interior LineStrings will be closed.

Examples
use geo_types::{coord, LineString, Polygon};

let mut polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![LineString::from(vec![
        (0.1, 0.1),
        (0.9, 0.9),
        (0.9, 0.1),
        (0.1, 0.1),
    ])],
);

polygon.interiors_mut(|interiors| {
    interiors[0].0[1] = coord! { x: 0.8, y: 0.8 };
});

assert_eq!(
    polygon.interiors(),
    &[LineString::from(vec![
        (0.1, 0.1),
        (0.8, 0.8),
        (0.9, 0.1),
        (0.1, 0.1),
    ])]
);

If the first and last Coordinates of any interior LineString no longer match, those LineStrings will be closed:

use geo_types::{coord, LineString, Polygon};

let mut polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![LineString::from(vec![
        (0.1, 0.1),
        (0.9, 0.9),
        (0.9, 0.1),
        (0.1, 0.1),
    ])],
);

polygon.interiors_mut(|interiors| {
    interiors[0].0[0] = coord! { x: 0.1, y: 0.2 };
});

assert_eq!(
    polygon.interiors(),
    &[LineString::from(vec![
        (0.1, 0.2),
        (0.9, 0.9),
        (0.9, 0.1),
        (0.1, 0.1),
        (0.1, 0.2),
    ])]
);

Add an interior ring to the Polygon.

The new LineString interior ring will be closed:

Examples
use geo_types::{coord, LineString, Polygon};

let mut polygon = Polygon::new(
    LineString::from(vec![(0., 0.), (1., 1.), (1., 0.), (0., 0.)]),
    vec![],
);

assert_eq!(polygon.interiors().len(), 0);

polygon.interiors_push(vec![(0.1, 0.1), (0.9, 0.9), (0.9, 0.1)]);

assert_eq!(
    polygon.interiors(),
    &[LineString::from(vec![
        (0.1, 0.1),
        (0.9, 0.9),
        (0.9, 0.1),
        (0.1, 0.1),
    ])]
);
👎 Deprecated since 0.6.1:

Please use geo::is_convex on poly.exterior() instead

Determine whether a Polygon is convex

Trait Implementations

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Converts to this type from the input type.

Converts to this type from the input type.

Converts to this type from the input type.

Feeds this value into the given Hasher. Read more

Feeds a slice of this type into the given Hasher. Read more

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

Convert a Geometry enum into its inner type.

Fails if the enum case does not match the type you are trying to convert it to.

The type returned in the event of a conversion error.

Performs the conversion.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

🔬 This is a nightly-only experimental API. (toowned_clone_into)

Uses borrowed data to replace owned data, usually by cloning. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.