latest

src/vec3.rs

@@ -12,6 +12,10 @@ impl Vec3 {
         Vec3 { elements: [x, y, z] }
     }
 
+    pub fn new_empty() -> Self {
+        Vec3::new(0.0, 0.0, 0.0)
+    }
+
     pub fn x(&self) -> f64 {
         self.elements[0]
     }
@@ -59,6 +63,11 @@ impl Vec3 {
     pub fn random_range(min: f64, max: f64) -> Self {
         Vec3::new(random_range_f64(min, max), random_range_f64(min, max), random_range_f64(min, max))
     }
+
+    pub fn near_zero(&self) -> bool {
+        let s = 1e-8;
+        (self.x().abs() < s) && (self.y().abs() < s) && (self.z().abs() < s)
+    }
 }
 
 impl Add for Vec3 {
@@ -212,4 +221,8 @@ pub fn random_in_hemisphere(normal: &Vec3) -> Vec3 {
     } else {
         return -in_unit_sphere;
     }
+}
+
+pub fn reflect(v: &Vec3, n: &Vec3) -> Vec3 {
+    *v - 2.0 * v.dot(n) * *n
 }