can make a ppm

src/main.rs

@@ -1,6 +1,10 @@
+use canvas::Canvas;
+use color::Color;
 use structs::Tuple;
 
 use std::fmt;
+use std::fs::File;
+use std::io::prelude::*;
 
 #[derive(Debug)]
 struct Environment {
@@ -57,15 +61,30 @@ fn main() {
 
     let mut ball = Projectile::new(
         Tuple::point(0.0, 0.0, 1.0),
-        Tuple::vector(10.0, 0.0, 100.0),
+        Tuple::vector(2.2, 0.0, 21.0),
     );
 
-    let mut tick = 0;
-    println!("tick {} the ball {}", tick, ball);
-    while ball.position.z() > 0.0 {
-        ball.tick(&env);
+    let mut canvas = Canvas::new(300, 300);
+    let color = Color::new(1.0, 1.0, 0.0);
+    while ball.position.z() < canvas.height() as f32
+        && ball.position.z() >= 0.0
+        && ball.position.x() < canvas.width() as f32
+        && ball.position.x() >= 0.0 {
+        canvas.write_pixel(ball.position.x() as usize, canvas.height() - ball.position.z() as usize, color);
 
-        println!("tick {} the ball {}", tick, ball);
-        tick += 1;
+        ball.tick(&env);
     }
+
+    let ppm = canvas.to_ppm();
+
+    let mut f = match File::create("out.ppm") {
+        Ok(f) => f,
+        Err(e) => panic!("file error. {}", e),
+    };
+
+    let _ = match f.write_all(ppm.as_bytes()) {
+        Ok(w) => w,
+        Err(e) => panic!("did not write. {}", e),
+    };
+
 }