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diff --git a/hw6/src/camera.cpp b/hw6/src/camera.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 <cmath>
+
+#include "constants.h"
+#include "camera.h"
+
+/////////////////
+// Constructor //
+/////////////////
+camera::camera(void)
+{
+  _eye = vec3d();
+  _view = vec3d(0.0f, 0.0f, -1.0f);
+  _up = vec3d(0.0f, 1.0f, 0.0f);
+  _fov = 60.0f;
+  _width = _height = 256;
+}
+
+
+camera::camera(const vec3d& eye, const vec3d& viewDirection, const vec3d& up, float fov, size_t xres, size_t yres)
+{
+  _eye = eye;
+  _view = normalize(viewDirection);
+  _up = normalize(up);
+  _fov = fov;
+  _width = xres;
+  _height = yres;
+
+  // fix up if needed
+  vec3d right = _view.cross(up).normalize();
+  _up = right.cross(_view).normalize();
+}
+
+
+camera::camera(const camera& cam)
+{
+  _eye = cam._eye;
+  _view = cam._view;
+  _up = cam._up;
+  _fov = cam._fov;
+  _width = cam._width;
+  _height = cam._height;
+}
+
+
+///////////////
+// Operators //
+///////////////
+camera& camera::operator=(const camera& cam)
+{
+  _assign(cam);
+  return *this;
+}
+
+
+ray camera::operator()(float x, float y) const
+{
+  vec3d right = _view.cross(_up).normalize();
+
+  // aspect ratio
+  float aspect = (float)(_height) / (float)(_width);
+  float tanFov = tan(_fov / 180.0f * PI);
+
+  // compute view plane center, and U and V unnormalized axes.
+  vec3d center = _eye + _view;
+  vec3d U = 2.0f * tanFov * right;
+  vec3d V = -2.0f * tanFov * aspect * _up;  // y runs from top to bottom (opposite direction of up)
+
+  // get point on view plane
+  vec3d p = center + (x / (float)(_width) - 0.5f) * U + (y / (float)(_height) - 0.5f) * V;
+
+  // Done.
+  return ray(_eye, p - _eye);
+}
+
+
+//////////////
+// Mutators //
+//////////////
+void camera::frameBoundingBox(const boundingBox& bb)
+{
+  // determine the best eye location, given the other parameters and a bounding box such that the bounding box maximally occupies the view
+  vec3d right = _view.cross(_up).normalize();
+  _eye = 0.5f * (bb.corner(true,true,true) + bb.corner(false,false,false));
+
+  // => find max projection in up and right direction.
+  float maxRight=-LARGE, maxUp=-LARGE, maxDepth=-LARGE;
+  for(unsigned int i=0; i < 8; i++)
+  {
+    vec3d c = bb.corner( (i&1)==1, (i&2)==2, (i&4)==4 ) - _eye;
+    
+    float r = fabs(c.dot(right));
+    float u = fabs(c.dot(_up));
+    float d = fabs(c.dot(_view));
+
+    maxRight = std::max(maxRight, r);
+    maxUp = std::max(maxUp, u);
+    maxDepth = std::max(maxDepth, d);
+  }
+
+  // => compute optimal distance for up and right
+  float aspect = (float)(_height) / (float)(_width);
+  float tanFov = tan(_fov / 180.0f * PI);
+  float optDistUp = fabs(maxUp / tanFov);
+  float optDistRight = fabs(maxRight / (tanFov * aspect));
+  
+  // => move _eye back based on (max) optimal distance
+  _eye -= _view * (std::max(optDistUp, optDistRight) + maxDepth);
+}
+
+
+/////////////////////
+// Private Methods //
+/////////////////////
+void camera::_swap(camera& cam)
+{
+  // sanity check
+  if(&cam == this) return;
+
+  // swap
+  swap(_eye, cam._eye);
+  swap(_view, cam._view);
+  swap(_up, cam._up);
+  std::swap(_fov, cam._fov);
+  std::swap(_width, cam._width);
+  std::swap(_height, cam._height);
+}
+
+
+void camera::_assign(const camera& cam)
+{
+  // sanity check
+  if(&cam == this) return;
+
+  // copy
+  _eye = cam._eye;
+  _view = cam._view;
+  _up = cam._up;
+  _fov = cam._fov;
+  _width = cam._width;
+  _height = cam._height;
+}