bowtie 0.2.0

2D Game engine with messaging system
Documentation 
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use std::collections::HashMap;

pub const PI: f32 = 3.14159265358979;
const ACCURACY_TAYLOR_SERIES: i32 = 12;

fn factorial_memoized(num: i32, memo_arr: *mut HashMap<i32, i32>) -> i32 {
  if num == 1 || num == 0 {
    return 1;
  }

  unsafe {
    let result: i32 = match (*memo_arr).get(&num) {
      Some(res) => res.to_owned(),
      None => {
        let n_less_1 =
          factorial_memoized(num.to_owned() - 1, memo_arr) * num.to_owned();
        (*memo_arr).insert(num.to_owned(), n_less_1);
        return n_less_1;
      }
    };

    return result;
  }
}

pub fn factorial(num: i32) -> i32 {
  let mut memo_arr = HashMap::<i32, i32>::new();
  return factorial_memoized(num, &mut memo_arr);
}

pub fn get_radian(theta: f32) -> f32 {
  (theta / 180.0) * PI
}

pub fn get_sin(theta: f32) -> f32 {
  let radian = get_radian(theta);
  let mut sin = radian.to_owned();
  let mut sub = true;
  for i in 2..ACCURACY_TAYLOR_SERIES {
    if i % 2 != 0 {
      continue;
    }
    let res = radian.powi(1 + i) / factorial(1 + i) as f32;
    sin = if sub { sin - res } else { sin + res };
    sub = !sub;
  }
  sin
}

pub fn get_cos(theta: f32) -> f32 {
  let radian = get_radian(theta);
  let mut cos = 1.0;
  let mut sub = true;
  for i in 1..ACCURACY_TAYLOR_SERIES {
    if i % 2 == 0 {
      continue;
    }
    println!("x^{}!", i + 1);
    let res = radian.powi(1 + i) / factorial(1 + i) as f32;
    cos = if sub { cos - res } else { cos + res };
    sub = !sub;
  }
  cos
}