Function normalise

native/shared/src/renderer/planar_reflection.rs:275–283

(v: [f32; 3])

}

fn normalise(v: [f32; 3]) -> [f32; 3] {
    let len_sq = v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
    if len_sq < 1e-10 {
        // Default to +Y — a horizontal mirror like a calm lake.
        return [0.0, 1.0, 0.0];
    }
    let inv = 1.0 / len_sq.sqrt();
    [v[0] * inv, v[1] * inv, v[2] * inv]
}

// =====================================================================
// Tests