earths 0.0.1

High-fidelity Earth simulation engine — orbit, atmosphere, geology, hydrology, biosphere, terrain, lighting, rendering, satellites, and temporal systems with full scientific coupling
Documentation 
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#[derive(Debug, Clone, Copy, PartialEq)]
pub enum CloudType {
    Cumulus,
    Stratus,
    Cirrus,
    Cumulonimbus,
    Altocumulus,
}
pub struct CloudLayer {
    pub cloud_type: CloudType,
    pub base_altitude_m: f64,
    pub thickness_m: f64,
    pub coverage: f64,
    pub density: f64,
    pub wind_speed_ms: f64,
    pub wind_direction: [f64; 2],
}
impl CloudLayer {
    pub fn cumulus() -> Self {
        Self {
            cloud_type: CloudType::Cumulus,
            base_altitude_m: 2_000.0,
            thickness_m: 1_500.0,
            coverage: 0.4,
            density: 0.3,
            wind_speed_ms: 8.0,
            wind_direction: [1.0, 0.0],
        }
    }
    pub fn stratus() -> Self {
        Self {
            cloud_type: CloudType::Stratus,
            base_altitude_m: 500.0,
            thickness_m: 500.0,
            coverage: 0.7,
            density: 0.5,
            wind_speed_ms: 5.0,
            wind_direction: [0.7, 0.7],
        }
    }
    pub fn cirrus() -> Self {
        Self {
            cloud_type: CloudType::Cirrus,
            base_altitude_m: 8_000.0,
            thickness_m: 1_000.0,
            coverage: 0.3,
            density: 0.05,
            wind_speed_ms: 30.0,
            wind_direction: [1.0, 0.2],
        }
    }
    pub fn cumulonimbus() -> Self {
        Self {
            cloud_type: CloudType::Cumulonimbus,
            base_altitude_m: 1_000.0,
            thickness_m: 12_000.0,
            coverage: 0.15,
            density: 0.8,
            wind_speed_ms: 15.0,
            wind_direction: [0.5, 0.5],
        }
    }
}
pub struct CloudSystem {
    pub layers: Vec<CloudLayer>,
    pub time_offset_s: f64,
}
impl CloudSystem {
    pub fn earth_default() -> Self {
        Self {
            layers: vec![
                CloudLayer::cumulus(),
                CloudLayer::stratus(),
                CloudLayer::cirrus(),
            ],
            time_offset_s: 0.0,
        }
    }
    pub fn step(&mut self, dt_s: f64) {
        self.time_offset_s += dt_s;
    }
    pub fn sample_density(&self, altitude_m: f64, _lat: f64, _lon: f64) -> f64 {
        let mut total = 0.0;
        for layer in &self.layers {
            let top = layer.base_altitude_m + layer.thickness_m;
            if altitude_m >= layer.base_altitude_m && altitude_m <= top {
                let t = (altitude_m - layer.base_altitude_m) / layer.thickness_m;
                let profile = 4.0 * t * (1.0 - t);
                total += layer.density * layer.coverage * profile;
            }
        }
        total.min(1.0)
    }
}