Method update

src/shot.rs:21–29

(&mut self, delta: Duration)

        }
    }
    pub fn update(&mut self, delta: Duration) {
        self.timer.tick(delta);
        if self.timer.finished() && !self.exploding {
            if self.y > 0 {
                self.y -= 1;
            }
            self.timer.reset();
        }
    }
    pub fn explode(&mut self) {
        self.exploding = true;
        self.timer = Timer::new(Duration::from_millis(250));