Digital Lighting

Spring Quarter, 2000
Instructor: Matthew Lewis

Meeting Times: TR, 10:30am to 12:18pm
Office Hours: by appt.
Course Number: Art 894.12
Call Number: 01968-5
Credits: 3
Location: 1224 Kinnear, Rm 0238 (ACCAD Classroom)

This course provides an introductory study of the mathematical models used in computer graphics to mimic the physical behavior of light in the generation of three-dimensional, computer-generated imagery. In addition, the course addresses the issues of visual storytelling through the application of cinematic techniques in the digital domain. The course is intended for students without a technical background in computer graphics.

Permission of instructor
3D modeling/rendering experience (e.g. ACCAD 750 or equiv).

Course Objectives and Student Learning Outcomes:
The generation of compelling synthetic imagery is primarily dependent upon two issues in computer graphics: the geometric shape of objects in the digital world and the illumination of those objects. This course will concentrate on the latter concern, the interplay of geometry and light, and discuss the physical reality, the computational models, and the application of cinematographic techniques in the digital domain. Students will develop the skills to use digital lighting for the purposes of storytelling and visual communication. They will also learn the mathematics and physics behind the simulation of light, texture, and form in computer graphics, and apply that knowledge by writing their own RenderMan shaders. Students will be encouraged to explore a broad range of styles, from photorealistic, to painterly, to cartoon-style.

The course will additionally enhance the students' ability to utilize lighting and shading for storytelling and visual communication. Each student will be expected to master fundamental, theoretical concepts in digital lighting, thus allowing them to use rendering software dependent upon those concepts more effectively and efficiently. Students will also gain necessary skills and experience to produce customized light and shading models, which provide aesthetic possibilities not available in "off-the-shelf" packages.

Course Methodology
The course will attempt to survey the important issues surrounding the creation of virtual lights and the surfaces they illuminate in digital environments. The different types of lighting and surfaces employed in computer graphics, as well as their respective effects, will be examined. Images illustrating different lighting approaches will be shown whenever possible, but students will learn primarily by creating and lighting their own objects and environments. The class format will take on a variety of styles as the disparate subjects dictate. Examples will be presented in lectures and demonstrations. Students will present their images in critique sessions.

Students must demonstrate satisfactory achievement of course objectives through fulfillment of course projects and by contributing to class discussions and critiques. Course projects will require students to use a wide variety of software and equipment at ACCAD to produce images and shaders. Collaboration between students in the course and other faculty, staff and students at ACCAD is encouraged. Course evaluation will be based on the following:

Projects one through six: 10% each
Final Project: 30%
Class Participation: 10%

Grading Policies:
All students are required to be on time and in attendance for each and every class. Students arriving to class more than 10 minutes late will be counted as absent. Two absences will lower a final grade by 1/2 a letter, three absences will lower a final grade by one letter and four absences will result in failure of the course.

Adherence to deadlines is expected. It is the individual student's responsibility to keep track of deadlines and to present the work to the class and instructor on the specified dates. 15% per day will be subtracted from late assignments.

Students choosing to use "at home" hardware and software must have their current working files on the system and available for review at the beginning of each and every class. Problems with home systems and/or incompatibility will not be an acceptable excuse for missed goals. Technical problems will happen frequently during the semester and students will have trouble accessing the computer lab during "prime time" hours. Students must make their own arrangements for overcoming these difficulties and submitting their work on time. Unless there is a complete system failure in a computer-related course, technical difficulties are never an acceptable excuse for not meeting a deadline. Students should plan their time and work so as to anticipate the technical hurdles that are a part of this profession.

A  = 94 - 100   A-  =  91 - 93
B+ = 89 - 90    B   =  83 - 88   B- = 80 - 82
C+ = 78 - 79    C   =  73 - 77   C- = 71 - 72
D+ = 69 - 70    D   =  64 - 68   E  = 0  - 64
Topics and Assignments:

Topics by week:
  1. Introduction and Design
    1. What is Digital Lighting? (Text: ch. 1)
    2. Cinematography Documentary: "Visions of Light"
    3. Lighting Techniques for Computer Generated Imagery (Kahrs AND Text: ch. 13)
    4. Storytelling with lighting
    5. Composition
  2. Physics of lighting (Text: 2.3 AND Glassner handout)
    1. The human eye
    2. Wave vs. ray models
    3. Color
    4. Surface reflection
    5. Assignment #1
  3. Computer Lighting Models
    1. Math for illumination models (Text: 2.1.1-5)
    2. Light and surface physics
    3. Illumination Model examples
  4. RenderMan
    1. Introduction to renderer(s) (Text: ch. 3)
    2. RenderMan shading language (Text: ch. 7)
    3. Functions in digital images
    4. Assignment #2
  5. Surface Shading Fundamentals (Text: ch. 9)
    1. Illumination
    2. Surface geometry
    3. Surface generation techniques
    4. Color and shape generation (Text: section 10.1)
    5. Layering and compositing (Text: 12.1)
    6. Aliasing and Antialiasing (Text: ch. 11)
    7. Assignment #3
  6. Regular patterns (Text: 10.2)
    1. Assignment #4
  7. Advanced Procedural Techniques
    1. Bump and Displacement shaders (Text: 8.2)
    2. Stochastic patterns (Text: 10.3)
    3. Assignment #5
  8. Solid textures
    1. Turbulence (Text: 10.4)
    2. Assignment #6
  9. Advanced Lighting Techniques
    1. Light shaders (Text: 9.6)
    2. Shadow generation
    3. Reflectance modeling (Text: 17.5)
    4. Global Illumination
  10. Non-photorealistic lighting models (Text: 16)
    1. Simulating flat media (Text: 16.3)
    2. Indirect rendering with RenderMan (Text: 16.4)
    3. Assignment #7


  1. Black and white still life: light quantity and distribution - 4/6/00
  2. Color study: setting mood, time of day - 4/18/00
  3. Crafting functions - 4/25/00
  4. Plastic study (controlling specularity, roughness, etc.) - 5/2/00
  5. Procedural surfaces: color washes and texture files - 5/9/00
  6. Generating regular patterns - 5/23/00
  7. Final project - 6/6/00

Student Work: [2000]
(Previous work: Steve May's Image Gallery and Shader Gallery)

Reading List:
Apodaca, Anthony A. and Larry Gritz. Advanced RenderMan: Creating CGI for Motion Pictures, Morgan Kaufmann, 2000. ISBN 1-55860-618-1.

Glassman, Arnold, Todd McCarthy and Stuart Samuels (directors) Visions of Light: The Art of Cinematography, American Film Institute / NHK Japan Broadcasting Corporation, 1992.

Glassner, Andrew S. "Surface Physics for Ray Tracing" from An Introduction to Ray Tracing. Academic Press, 1989. (handout)

Kahrs, John, Sharon Calahan, Dave Carson, and Stephen Poster, A.S.C., "Pixel Cinematography: A Lighting Approach for Computer Graphics," ACM Siggraph Course Notes #30, 1996.
(local on NTs in Network Neighborhood\Leave\Share\Pdfs)

Library Resources:
Alton, John. Painting with Light, University of California Press, 1995. (Originally published by Macmillan, 1947.) ISBN 0-520-08949-9.

Ebert, Dave, Ken Musgrave, Darwyn Peachey, Ken Perlin, and Steve Worley. Texturing and Modeling: A Procedural Approach, AP Professional, 1994. ISBN 0-12-228760-6.

Keller, Max. Light Fantastic: The Art and Design of Stage Lighting. Prestel Verlag, 1999.

Malkiewicz, Kris. Film Lighting, Prentice Hall Press, 1986. ISBN 0671622714.

Upstill, Steve. The RenderMan Companion: A Programmer's Guide to Realistic Computer Graphics, Addison-Wesley, 1990. ISBN 0-201-50868-0.

This course was originally written by Stephen May.