lj_rust/src/transformer/rotate.rs

use crate::point::Point;
use crate::transformer::Transformers;
use crate::worldstate::WorldState;

use serde::{Deserialize, Serialize};
//use std::f32::consts::PI;

/// Rotate

#[derive(Serialize, Deserialize, Debug, Clone, Copy)]
pub struct Rotate {
    cx: f32,
    cy: f32,
    angle: f32,
}

impl Transformers for Rotate {
    fn apply(&self, point_list: &[Point], _ws: &WorldState) -> Vec<Point> {
        point_list
            .iter()
            .map(|pt| {
                let dx = pt.x - self.cx;
                let dy = pt.y - self.cy;
                let cos = self.angle.cos();
                let sin = self.angle.sin();
                let x = (dx * cos - dy * sin) + self.cx;
                let y = (dx * sin + dy * cos) + self.cy;
                Point { x, y, ..*pt }
            })
            .collect()
    }
}