added timer

src/main.rs

@@ -7,7 +7,7 @@ pub mod hittable_list;
 pub mod rtweekend;
 pub mod camera;
 
-use std::{io::{BufWriter, Write}, fs::File};
+use std::{io::{BufWriter, Write}, fs::File, time::Instant};
 
 use crate::{
     color::*,
@@ -57,6 +57,7 @@ fn main() {
 
     // Render
     //let mut rng = rand::thread_rng();
+    let now = Instant::now();
     let mut file = BufWriter::new(File::create("img.ppm").expect("File creation failed"));
 
     write!(file, "P3\n{image_width} {image_height}\n255").expect("Error while writing Magic Byte");
@@ -78,4 +79,8 @@ fn main() {
 
         println!("[ {:.2} % ]", (1.0 - ((j + 1) as f64 / image_width as f64)) * 100.0);
     }
-}
+    println!("Took {:.6}ms", now.elapsed().as_millis());
+    println!("Took {:.6}s", now.elapsed().as_secs_f64());
+    println!("Took {:.6}m", now.elapsed().as_secs_f64() / 60.0);
+    println!("Took {:.6}h", now.elapsed().as_secs_f64() / 3600.0);
+}