Created a Projectile and allowed it to be operated on by wind and gravity

src/main.rs

@@ -1,3 +1,71 @@
-fn main() {
-    println!("Hello, world!");
+use structs::Tuple;
+
+use std::fmt;
+
+#[derive(Debug)]
+struct Environment {
+    gravity: Tuple,
+    wind: Tuple,
+}
+
+#[derive(Debug, Clone, Copy)]
+struct Projectile {
+    position: Tuple,
+    velocity: Tuple,
+}
+
+impl Projectile {
+
+    fn new(position: Tuple, velocity: Tuple) -> Projectile {
+        if !position.is_point() {
+            panic!("position can not be a vector");
+        }
+
+        if !velocity.is_vector() {
+            panic!("velocity can not be point");
+        }
+
+        Projectile {
+            position: position,
+            velocity: velocity,
+        }
+    }
+}
+
+impl Projectile {
+    fn tick(&mut self, env: &Environment) {
+        self.position = self.position + self.velocity;
+        self.velocity = env.wind + env.gravity;
+    }
+}
+
+impl fmt::Display for Projectile {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "pos: {}, vel {}", self.position, self.velocity)
+    }
+}
+
+fn init_env() -> Environment {
+    Environment {
+            gravity: Tuple::vector(0.0, 0.0, -0.98),
+            wind: Tuple::vector(0.0, 0.0, 0.0),
+    }
+}
+
+fn main() {
+    let env = init_env();
+
+    let mut ball = Projectile::new(
+        Tuple::point(0.0, 0.0, 1.0),
+        Tuple::vector(1.0, 0.0, 0.0),
+    );
+
+    let mut tick = 0;
+    println!("tick {} the ball {}", tick, ball);
+    while ball.position.z() > 0.0 {
+        ball.tick(&env);
+
+        println!("tick {} the ball {}", tick, ball);
+        tick += 1;
+    }
 }