float_to_heat.rs

use serde::{Deserialize, Serialize};

#[derive(PartialEq, Clone, Serialize, Deserialize)]
pub struct HeatColor {
    r: u8,
    g: u8,
    b: u8,
    a: f32,
}

impl Default for HeatColor {
    fn default() -> Self {
        HeatColor {
            r: 0,
            g: 0,
            b: 0,
            a: 0.0,
        }
    }
}

impl HeatColor {
    pub fn new(value: Option<f64>) -> Self {
        if let Some(value) = value {
            let ratio = 2.0 * value;
            let b = ((255.0 * (1.0 - ratio)) as u8).max(0);
            let r = ((255.0 * (ratio - 1.0)) as u8).max(0);
            let g = 255 - b - r;
            HeatColor { r, g, b, a: 1.0 }
        } else {
            HeatColor::default()
        }
    }
    pub fn string(&self) -> String {
        format!("rgba({},{},{},{})", self.r, self.g, self.b, self.a)
    }
}