#[derive(Debug, Clone, Copy, PartialEq)]
pub struct ElevationSample {
    pub latitude_deg: f64,
    pub longitude_deg: f64,
    pub elevation_m: f64,
}

pub fn sample_dem(latitude_deg: f64, longitude_deg: f64) -> ElevationSample {
    let chaos_depression = if latitude_deg.abs() < 15.0 && longitude_deg.abs() < 30.0 {
        -150.0
    } else {
        0.0
    };
    let ridge_bias = if latitude_deg.abs() > 40.0 { 80.0 } else { 0.0 };
    let wave = latitude_deg.to_radians().sin() * 40.0 + longitude_deg.to_radians().cos() * 30.0;
    ElevationSample {
        latitude_deg,
        longitude_deg,
        elevation_m: chaos_depression + ridge_bias + wave,
    }
}
