feat: Reflections

src/raycolor.cpp

@@ -3,6 +3,8 @@
 #include "blinn_phong_shading.h"
 #include "reflect.h"
 
+const double FUDGE_FACTOR = 1e-6;
+
 // Hint: for the mirror reflections, you can use raycolor recursively. That is what 'num_recursive_calls' is for.
 // The maximum number of recursive calls should be 10. In other words, to get the color of a mirror reflection,
 // stop after 10 bounces.
@@ -17,7 +19,8 @@ bool raycolor(
 {
     int hit_id;
     double t;
-    Eigen::Vector3d n;
+    Eigen::Vector3d n, reflect_rgb;
+    Ray reflect_ray;
 
     /* Compute viewing array. */
     if (!first_hit(ray, min_t, objects, hit_id, t, n)) {
@@ -27,5 +30,16 @@ bool raycolor(
 
     /* Evaluate shading model and set pixel to that color. */
     rgb = blinn_phong_shading(ray, hit_id, t, n, objects, lights);
+
+    if (num_recursive_calls >= 10) {
+        return true;
+    }
+
+    /* Reflections */
+    reflect_ray.origin = ray.origin + t * ray.direction;
+    reflect_ray.direction = reflect(ray.direction, n);
+    raycolor(reflect_ray, FUDGE_FACTOR, objects, lights, num_recursive_calls + 1, reflect_rgb);
+    rgb += (objects[hit_id]->material->km.array() * reflect_rgb.array()).matrix();
+
     return true;
 }

src/reflect.cpp

@@ -2,6 +2,5 @@
 
 Eigen::Vector3d reflect(const Eigen::Vector3d & in, const Eigen::Vector3d & n)
 {
-  // Replace with your code here:
-  return Eigen::Vector3d(0,0,0);
+    return in - 2 * in.dot(n) * n;
 }