New scatter formula

vec3.hpp

@@ -159,4 +159,20 @@ vec3 random_in_unit_sphere()
     }
 }
 
+// Returns a normalized version of the above vector
+vec3 random_unit_vector()
+{
+    return normalize(random_in_unit_sphere());
+}
+
+vec3 random_in_hemisphere(const vec3& normal)
+{
+    vec3 in_unit_sphere = random_in_unit_sphere();
+    
+    if (dot(in_unit_sphere, normal) > 0.0)
+        return in_unit_sphere;
+    else
+        return -in_unit_sphere;
+}
+
 #endif