Struct PathBaseline 

pub struct PathBaseline<const N: usize> {
    pub positions: [LatLon; N],
    pub perpendiculars: [TangentMetres; N],
    pub perp_scale_pos: [f64; N],
    pub perp_scale_neg: [f64; N],
}

Reference path that the init families perturb.

Each particle is built by walking the baseline and adding offset[i] * scale[i] metres along perpendiculars[i] at every interior waypoint. Scale is perp_scale_pos for offset ≥ 0, perp_scale_neg otherwise — asymmetric so a polyline running closer to one coast can still wiggle freely on the other side. Decouples “where the path goes” from “how particles vary.”

Fields

positions: [LatLon; N]

perpendiculars: [TangentMetres; N]

Outward perpendicular, unit east-north tangent (90° CCW of the local tangent direction).

perp_scale_pos: [f64; N]

Perturbation scale (metres) for the +perpendicular side.

perp_scale_neg: [f64; N]

Perturbation scale (metres) for the −perpendicular side.

Implementations

impl<const N: usize> PathBaseline<N>

pub fn straight_line(bounds: &RouteBounds) -> Self

Straight-line lerp baseline. Symmetric scale = half the haversine route length on both sides.

pub fn from_polyline<LS: LandmassSource>( polyline: &[LatLon], bounds: &RouteBounds, landmass: &LS, ) -> Self

Topology-aware baseline from a polyline (e.g. an A* sea path). Samples N waypoints uniformly by arc length and probes the signed-distance field for the perpendicular clearance on each side, so a path running close to one coast still wiggles freely on the open-sea side.

pub fn from_polyline_land_respecting<LS: LandmassSource>( polyline: &[LatLon], bounds: &RouteBounds, landmass: &LS, ) -> Self

Sampler that prioritises land-free chords over uniform spacing. Use for benchmark routes (unperturbed xy) so “Bench land” reads 0 on a correctly-routed input. Not for PSO init seeds — tighter sampling hugs the coastline, and perpendicular kicks then push particles into land too often.

Trait Implementations

impl<const N: usize> Clone for PathBaseline<N>

fn clone(&self) -> PathBaseline<N>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<const N: usize> Debug for PathBaseline<N>

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

Formats the value using the given formatter.