rustial-engine 0.0.1

Framework-agnostic 2.5D map engine for rustial
Documentation 
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//! Geographic wrap/normalization helpers.

/// Wrap longitude into the canonical `[-180, 180)` degree range.
#[inline]
pub fn wrap_lon_180(lon: f64) -> f64 {
    ((lon + 180.0).rem_euclid(360.0)) - 180.0
}

/// Compute a `to_lon` value (equivalent modulo 360) that is closest to `from_lon`.
///
/// This matches the "shortest path" longitude behavior used by Mapbox/MapLibre
/// camera animations when crossing the antimeridian.
#[inline]
pub fn shortest_lon_target(from_lon: f64, to_lon: f64) -> f64 {
    let from = wrap_lon_180(from_lon);
    let to = wrap_lon_180(to_lon);

    // delta in [-180, 180]
    let mut d = (to - from).rem_euclid(360.0);
    if d > 180.0 {
        d -= 360.0;
    }
    from + d
}