Struct Leg 

pub struct Leg {
    pub from: Position,
    pub to: Position,
    pub port_xtd_nm: f64,
    pub starboard_xtd_nm: f64,
    pub sailing: Sailing,
}

One leg of a route, with the water it is allowed to wander into.

Known limitation: a leg crossing the antimeridian is not handled. The band is built in longitude and latitude, so a leg from 179°E to 179°W would be drawn the long way around the world, checking the wrong hemisphere. Splitting such a leg at 180° and checking the halves separately would fix this; not yet implemented.

Fields

from: Position

Where the leg starts.

to: Position

Where it ends.

port_xtd_nm: f64

How far the vessel may stray to port of the track, in nautical miles.

starboard_xtd_nm: f64

The same to starboard.

sailing: Sailing

How the leg is drawn.

Implementations

impl Leg

pub fn symmetric(from: Position, to: Position, half_width_nm: f64) -> Self

A leg with the same tolerance to port and starboard, for a caller with a single corridor figure and no route to supply per-side values.

pub fn length_nm(&self) -> f64

The leg’s length, measured the way the leg is drawn.

pub fn narrowest_xtd_nm(&self) -> f64

The tighter of the two tolerances – the precision the chart data must resolve to, regardless of how much room the wider side allows.

pub fn point_at(&self, along_nm: f64) -> Position

The point along_nm from the start, on the track itself.

pub fn course_at(&self, position: Position, along_nm: f64) -> f64

The course being steered at a point on the track, degrees true.

Constant on a rhumb line; changes continuously on a great circle, so the band is offset from the local course at each point rather than from a single bearing for the whole leg.

pub fn band(&self) -> Option<Polygon<f64>>

The whole band, as one polygon, for the R-Tree index lookup, which requires a single bounding box.

None for a leg of zero length (no direction, hence no sides) or zero tolerance.

pub fn segments(&self) -> Vec<Segment>

The leg cut into pieces, in sailing order.

Checking piece by piece lets a check report the distance along the leg where a hazard is first met, rather than only that one exists.

Trait Implementations

impl Clone for Leg

fn clone(&self) -> Leg

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Leg

impl Debug for Leg

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq for Leg

fn eq(&self, other: &Leg) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Leg