• the only objects in the scene are generic spheres, planes, squares, tapered cylinders, and cubes.
• the objects may have been translated, scaled, and/or rotated with respect to an axis
• in addition to color, the attributes of each object may include material coefficients for diffuse, specular, ambient color
• in addition to material attributes,
  • all the objects may be textured with a 2D image
  • all the objects may be textured with a 3D generated texture, such as wood and marble
• the images are defined in ppm formatted files
• multiple lights may be placed in the scene
• each light has a diffuse, specular, and ambient component
  • each light may be
    • positional, specified by postion
      • positional spotlight, specified by
        • position
        • cutoff angle
        • spotlight direction
        • spot exponent
    • directional, specified by directional vector
• the light may be attenuated, specified by
  • kc, constant coefficient
  • kl, linear coefficient
  • kq, quadratic coefficient
• a value for global ambient light may be assigned
• shadows are correctly rendered, including on textured surface
• descriptions of the objects, lights, and camera, as well as the names of the image files, are read in from a file, using SDL
• value for backgroundColor is now read in from the scene description file, using SDL
• the ray tracer correctly handles reflections
  • value for maximum recursive depth (for calculating reflections) is read in from the scene description file, using SDL
  • value for "shininess" of an object (0.0 to 1.0) is read in from the scene description file, using SDL
• the ray tracer correctly handles the most basic transparencies (no shadows, no intersection of transparent objects):
  • value for index of refraction (refraction) is read in from the scene description file
  • value for transparency (0.0 to 1.0) is read in from the scene description file
• the ray tracer uses the Cook-Torrance Shading Model