• the only objects in the scene are generic spheres, generic planes, generic cubes, generic squares, and generic tapered cylinders, which may have been
  • scaled
  • translated
  • rotated with respected to an axis
    
    
• in addition to color, the attributes of the generic sphere may include material values for diffuse, specular, ambient color
  
• a positional light may be placed in the scene by specifying its position
  
• the light has a diffuse, specular, and ambient component
  
• a value for global ambient light may be assigned
  
• shadows are correctly rendered
  
• speedup: extents are used around each generic primitive (generic cube around the generic primitive is test first; if hit, then primitive is tested)
  
• the camera is set up
  • at position (eye_x, eye_y, eye_z),
    
  • looking at point (look_at_x, look_at_y, look_at_z), with
    
  • the original up-direction for the camera being <up_x, up_y, up_z>.
    
    
• speed-up has been accomplished by more wisely computing the ray's direction, for each ray.
  
• the scene (including camera information and sphere information) has been described in a file using Scene Description Language
  
• (*10) value for backgroundColor is now read in from the scene description file, using SDL