pub fn inside(&self, x: u32, y: u32) -> bool {
        let p = Vector2f::new(x as f32, y as f32);

        !self.under_slope(p, self.points[5], self.points[0])
            && !self.under_slope(p, self.points[0], self.points[1])
            && self.under_slope(p, self.points[2], self.points[3])
            && self.under_slope(p, self.points[3], self.points[4])
            && self.points[5].x <= p.x
            && p.x <= self.points[1].x
    }

    fn under_slope(&self, p: Vector2f, a: Vector2f, b: Vector2f) -> bool {
        // ignore verticals
        if a.x == b.x {
            return false;
        }

        let g = (a.y - b.y) / (a.x - b.x);
        let y = g * (p.x - a.x) + a.y;

        p.y < y
    }