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diff --git a/hw5/src/recursiveRaytracing.cpp b/hw5/src/recursiveRaytracing.cpp
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+/******************************************************************/
+/* This file is part of the homework assignments for CSCI-427/527 */
+/* at The College of William & Mary and authored by Pieter Peers. */
+/* No part of this file, whether altered or in original form, can */
+/* be distributed or used outside the context of CSCI-427/527     */
+/* without consent of either the College of William & Mary or     */
+/* Pieter Peers.                                                  */
+/******************************************************************/
+#include "ray_util.h"
+#include "random_number.h"
+#include "recursiveRaytracing.h"
+
+
+//////////////////
+// Constructors //
+//////////////////
+recursiveRaytracing::recursiveRaytracing(unsigned int maxDepth, unsigned int samplesPerPixel)
+{
+  _depth = maxDepth;
+  _samples = samplesPerPixel;
+}
+
+
+/////////////
+// Methods //
+/////////////
+image recursiveRaytracing::render(const scene& s) const
+{
+  image result(s.getCamera().width(), s.getCamera().height());
+
+  // HW5: Implement a recursive ray tracer that shoots '_samples' rays per pixel.
+  //      and has a maximum recursion depth of '_depth'. The ray tracer should
+  //      only recurse for specular surfaces, and support environment maps and
+  //      shadows.
+  // Modifes: nothing.
+  // Returns: rendered image.
+
+  // for each pixel
+  for (image::size_type y = 0; y < result.height(); y++) {
+
+    for (image::size_type x = 0; x < result.width(); x++) {
+
+      // for sample size 1, shoot ray at pixel center
+      if (_samples == 1) {
+        ray r = s.getCamera()(x + 0.5, y + 0.5);
+        result(x, y) = traceRay(s, r, _depth);
+      }
+      else {
+        // for each sample, trace all the rays!
+        color pixel = color(0.0f);
+
+        for (unsigned int i = 0; i < _samples; i++) {
+          ray r = s.getCamera()(x + random_float(1.0f), y + random_float(1.0f));
+          pixel += traceRay(s, r, _depth);
+        }
+
+        result(x, y) = pixel / _samples;
+      }
+
+    }
+
+  }
+
+  return result;
+}
+
+
+color recursiveRaytracing::traceRay(const scene& s, const ray& r, unsigned int currentDepth) const {
+  color result = color(0.0f);
+
+  // base case: bail at max depth
+  if (currentDepth == 0) {
+    return color();
+  }
+
+  // intersect the scene
+  intersectionPoint ip = s.intersect(r);
+
+  // if hit, shade pixel
+  if (ip.isHit()) {
+
+    // for each light source,
+    for (unsigned int l = 0; l < s.numberOfLightsources(); l++) {
+      // connect to light source
+      lightSample ls = s.getLightsource(l).intensityAt(ip.position());
+
+      // create shadow ray and intersect with light source
+      ray shadowRay = createRay(ip, ls.directionToLight());
+      intersectionPoint shadow_ip = s.intersect(shadowRay);
+
+      // if object not in shadow, shade it
+      if (!(ip.distance(shadow_ip) < ls.distance())) {
+        result += ip.shade(ls);
+      }
+
+    }
+
+    // if specular, compute indirect lighting and recurse
+    if (ip.getShaderProperties().specular) {
+      ray reflect_ray = reflectRay(ip);
+      intersectionPoint reflect_ip = s.intersect(reflect_ray);
+
+      if (reflect_ip.isHit()) {
+        result += (ip.shade(reflect_ray.direction()) * traceRay(s, reflect_ray, --currentDepth));
+      }
+      else {
+        // if scene has environment map, grab texel color from map
+        if (s.hasEnvironmentMap()) {
+          result += s.evaluateEnvironmentMap(reflect_ray.direction());
+        }
+
+      }
+
+    }
+
+  }
+  else {
+
+    // if scene has environment map, grab texel color from map
+    if (s.hasEnvironmentMap()) {
+      result += s.evaluateEnvironmentMap(r.direction());
+    }
+
+  }
+
+  return result;
+}