Add PNG output

src/main.rs

@@ -3,7 +3,7 @@ use std::time::Instant;
 
 use crate::camera::Camera;
 use crate::hittable::{Hittable, Sphere};
-use crate::output::{Output, P3};
+use crate::output::{Output, P3, PNG};
 use crate::ray::Ray;
 use crate::vec3::{Color, Point3, Vec3};
 use rand::distributions::{Distribution, Uniform};
@@ -86,9 +86,8 @@ fn main() {
     const ASPECT_RATIO: f64 = 3.0 / 2.0;
     const IMAGE_WIDTH: usize = 1200;
     const IMAGE_HEIGHT: usize = (IMAGE_WIDTH as f64 / ASPECT_RATIO) as usize;
-    const SAMPLES_PER_PIXEL: i32 = 500;
+    const SAMPLES_PER_PIXEL: i32 = 100;
     const MAX_DEPTH: i32 = 50;
-    let hh = IMAGE_HEIGHT;
 
     let look_from = Point3::new(13.0, 2.0, 3.0);
     let look_at = Point3::new(0.0, 0.0, 0.0);
@@ -138,6 +137,6 @@ fn main() {
             }
         }
     });
-    P3::write("imc.ppm", &pixels, IMAGE_WIDTH, IMAGE_HEIGHT).expect("Error writing image: {}");
+    PNG::write("imc.png", &pixels, IMAGE_WIDTH, IMAGE_HEIGHT).expect("Error writing image: {}");
     eprintln!("\nDone. Time: {}ms", start.elapsed().as_millis());
 }

src/output.rs

@@ -1,12 +1,14 @@
-use std::{fs::File, io::{Error, Write}};
+use std::{fs::File, io::{Error, Write, BufWriter, ErrorKind}};
+
+use image::ImageOutputFormat;
 
 pub trait Output {
-    fn write(filename: &str, pixels: &Vec<u8>, width: usize, height: usize) -> Result<File, Error>;
+    fn write(filename: &str, pixels: &Vec<u8>, width: usize, height: usize) -> Result<(), Error>;
 }
 
 pub struct P3 {}
 impl Output for P3 {
-    fn write(filename: &str, pixels: &Vec<u8>, width: usize, height: usize) -> Result<File, Error> {
+    fn write(filename: &str, pixels: &Vec<u8>, width: usize, height: usize) -> Result<(), Error> {
         let mut file = File::create(filename)?;
         file.write(format!("P3\n{} {}\n255\n", width, height).as_bytes())?;
         let lines: Result<Vec<usize>, Error> = pixels
@@ -14,6 +16,22 @@ impl Output for P3 {
             .map(|chunk| format!("{} {} {}\n", chunk[0], chunk[1], chunk[2]))
             .map(|line| file.write(line.as_bytes()))
             .collect();
-        lines.map(|_v| file)
+        lines.map(|_l|())
+    }
+}
+
+pub struct PNG {}
+impl Output for PNG {
+    fn write(filename: &str, pixels: &Vec<u8>, width: usize, height: usize) -> Result<(), Error> {
+        let file = File::create(filename)?;
+        let ref mut writer = BufWriter::new(file);
+        image::write_buffer_with_format(
+            writer,
+            pixels,
+            width as u32,
+            height as u32,
+            image::ColorType::Rgb8,
+            ImageOutputFormat::Png)
+            .map_err(|e|  Error::new(ErrorKind::Other, e))
     }
 }