Constant TREE_SWAY_WGSL 

pub const TREE_SWAY_WGSL: &str = r#"
fn tree_sway(rest: vec3f, pivot: vec3f, level: f32, stiffness: f32, wind_time: f32, strength: f32, direction: vec3f) -> vec3f {
    let d = normalize(direction.xz + vec2f(0.00001, 0.0));
    let arm = length(rest - pivot);
    let phase = wind_time * (0.7 + level * 0.41) + pivot.x * 0.83 + pivot.z * 0.67;
    let bend = sin(phase) * strength * (1.0 - stiffness) * arm * (0.012 + 0.009 * level);
    return rest + vec3f(d.x * bend, -abs(bend) * 0.12, d.y * bend);
}
"#;