vec3 type

.gitignore

@@ -1 +1,2 @@
 /target
+*.png

src/main.rs

@@ -1,6 +1,7 @@
 extern crate image;
 
-use std::fs::File;
+mod vec3;
+use vec3::Vec3;
 
 fn main() {
     let imgx = 320;
@@ -9,9 +10,8 @@ fn main() {
     let mut imgbuf = image::ImageBuffer::new(imgx, imgy);
 
     for (x, y, pixel) in imgbuf.enumerate_pixels_mut() {
-        let r = (x * 255 / imgx) as u8;
-        let g = (y * 255 / imgy) as u8;
-        *pixel = image::Rgb([r, g, 100]);
+        let v = Vec3::new(x as f32 / imgx as f32, y as f32 / imgy as f32, 0.4);
+        *pixel = v.to_rgb().unwrap();
     }
 
     imgbuf.save("hello.png").unwrap();

src/vec3.rs

@@ -0,0 +1,94 @@
+use std::ops::*;
+use std::f32;
+use image::Rgb;
+
+#[derive(Clone, Copy, Debug)]
+pub struct Vec3(f32, f32, f32);
+
+impl Vec3 {
+    pub fn new(x: f32, y: f32, z: f32) -> Vec3 {
+        Vec3(x, y, z)
+    }
+
+    pub fn length(&self) -> f32 {
+        (self.squared_length()).sqrt()
+    }
+
+    pub fn squared_length(&self) -> f32 {
+        self.0 * self.0 + self.1 * self.1 + self.2 * self.2
+    }
+
+    pub fn dot(&self, other: Vec3) -> f32 {
+        self.0 * other.0 + self.1 * other.1 + self.2 * other.2
+    }
+
+    pub fn cross(&self, other: Vec3) -> Vec3 {
+        Vec3(
+            self.1 * other.2 - self.2 * other.1,
+            self.2 * other.0 - self.0 * other.2,
+            self.0 * other.1 - self.1 * other.0,
+        )
+    }
+
+    pub fn unit(&self) -> Vec3 {
+        *self / self.length()
+    }
+
+    pub fn to_rgb(&self) -> Result<Rgb<u8>, &str> {
+        if self.0 < 0.0 || self.0 > 1.0 || self.1 < 0.0 || self.1 > 1.0 || self.2 < 0.0 || self.2 > 1.0 {
+           return Err("input out of bounds");
+        }
+        let r = (self.0 * 255.99) as u8;
+        let g = (self.1 * 255.99) as u8;
+        let b = (self.2 * 255.99) as u8;
+        Ok(Rgb([r, g, b]))
+    }
+}
+
+impl Add for Vec3 {
+    type Output = Vec3;
+
+    fn add(self, other: Vec3) -> Vec3 {
+        Vec3(self.0 + other.0, self.1 + other.1, self.2 + other.2)
+    }
+}
+
+impl Sub for Vec3 {
+    type Output = Vec3;
+
+    fn sub(self, other:Vec3) -> Vec3 {
+        Vec3(self.0 - other.0, self.1 - other.1, self.2 - other.2)
+    }
+}
+
+impl Neg for Vec3 {
+    type Output = Vec3;
+
+    fn neg(self) -> Vec3 {
+        Vec3(-self.0, -self.1, -self.2)
+    }
+}
+
+impl Mul<f32> for Vec3 {
+    type Output = Vec3;
+
+    fn mul(self, k: f32) -> Vec3 {
+        Vec3(self.0 * k, self.1 * k, self.2 * k)
+    }
+}
+
+impl Div<f32> for Vec3 {
+    type Output = Vec3;
+
+    fn div(self, k: f32) -> Vec3 {
+        Vec3(self.0 / k, self.1 / k, self.2 / k)
+    }
+}
+
+impl Mul<Vec3> for f32 {
+    type Output = Vec3;
+
+    fn mul(self, v: Vec3) -> Vec3 {
+        v*self
+    }
+}