eoc8: add third light for effect

rtchallenge/examples/eoc8.rs

@@ -33,12 +33,16 @@ fn main() -> Result<()> {
     let opt = Opt::from_args();
     let width = 2560;
     let height = 1440;
+
     let light_position = Tuple::point(-10., 10., -10.);
     let light_color = WHITE;
     let light1 = PointLight::new(light_position, light_color);
     let light_position = Tuple::point(10., 10., -10.);
-    let light_color = Color::new(0.0, 0.0, 1.0);
+    let light_color = Color::new(0.2, 0.2, 0.2);
     let light2 = PointLight::new(light_position, light_color);
+    let light_position = Tuple::point(0., 10., -10.);
+    let light3 = PointLight::new(light_position, light_color);
+
     let mut camera = Camera::new(width, height, PI / 4.);
     let from = Tuple::point(0., 1.5, -5.);
     let to = Tuple::point(0., 1., 0.);
@@ -87,7 +91,7 @@ fn main() -> Result<()> {
     right.material = Material {
         color: Color::new(1., 1., 1.),
         diffuse: 0.7,
-        specular: 0.3,
+        specular: 0.0,
         ..Material::default()
     };
 
@@ -103,7 +107,7 @@ fn main() -> Result<()> {
     };
 
     let mut world = World::default();
-    world.lights = vec![light1, light2];
+    world.lights = vec![light1, light2, light3];
     world.objects = vec![floor, left_wall, right_wall, middle, right, left];
 
     let image = camera.render(&world);