pub trait Area<T>where
T: CoordNum,{
// Required methods
fn signed_area(&self) -> T;
fn unsigned_area(&self) -> T;
}Expand description
Signed and unsigned planar area of a geometry.
§Examples
use geo::polygon;
use geo::Area;
let mut polygon = polygon![
(x: 0., y: 0.),
(x: 5., y: 0.),
(x: 5., y: 6.),
(x: 0., y: 6.),
(x: 0., y: 0.),
];
assert_eq!(polygon.signed_area(), 30.);
assert_eq!(polygon.unsigned_area(), 30.);
polygon.exterior_mut(|line_string| {
line_string.0.reverse();
});
assert_eq!(polygon.signed_area(), -30.);
assert_eq!(polygon.unsigned_area(), 30.);Required Methods§
fn signed_area(&self) -> T
fn unsigned_area(&self) -> T
Implementors§
impl<T> Area<T> for Geometry<T>where
T: CoordFloat,
impl<T> Area<T> for GeometryCollection<T>where
T: CoordFloat,
impl<T> Area<T> for Line<T>where
T: CoordNum,
impl<T> Area<T> for LineString<T>where
T: CoordNum,
impl<T> Area<T> for MultiLineString<T>where
T: CoordNum,
impl<T> Area<T> for MultiPoint<T>where
T: CoordNum,
impl<T> Area<T> for MultiPolygon<T>where
T: CoordFloat,
Note. The implementation is a straight-forward
summation of the signed areas of the individual
polygons. In particular, unsigned_area is not
necessarily the sum of the unsigned_area of the
constituent polygons unless they are all oriented the
same.
impl<T> Area<T> for Point<T>where
T: CoordNum,
impl<T> Area<T> for Polygon<T>where
T: CoordFloat,
Note. The implementation handles polygons whose holes do not all have the same orientation. The sign of the output is the same as that of the exterior shell.
impl<T> Area<T> for Rect<T>where
T: CoordNum,
Because a Rect has no winding order, the area will always be positive.