March 11, 1987

Alain Fournier
Xerox PARC/CSL
3333 Coyote Hill Road
Palo Alto, CA  94304

Dear Alain:

Congratulations on the acceptance of your paper A Programming Environment for Display Processes to the SIGGRAPH'87 technical 
program.
We represent an ad hoc subcommittee of the technical program committee that argued for and orchestrated a graphics systems session. 
 The lineup for the three papers in the graphics systems session, chaired by Rick Beach, looks like this:
A Programming Environment for Display Processes,
Tom Nadas, Alain Fournier, University of Toronto
FRAMES:  Software Tools for Modeling, Rendering and Animation of 3D Scenes,
Michael Potmesil, Eric M. Hoffert, AT&T Bell Laboratories
The Reyes Image Rendering Architecture,
Robert L. Cook, Loren Carpenter, Edwin Catmull, Pixar
Each of these papers represents a differing point of view about graphics systems.  We undertook to write additional reviews so as 
to encourage you to make your paper into a systems paper rather than the description of a rendering system.  The whys are vastly 
more important that the whats, and presently the papers do not say why well enough.  The enclosed review is intended to help you 
make a more lasting and useful contribution to the literature on graphic systems.
For the conference presentations, we would like to encourage each group to contrast its design with those of the other groups.  How 
is yours different, and why is it better?  We would be interested in knowing why your system is easy to use, easy to change, 
robust, and so on, to the extent that it is.  To encourage direct comparisons it may be useful for us to suggest a common example 
that each system could render.
To facilitate this, you may wish to circulate your paper among the other authors, so we have attached the mailing addresses of each 
contact person.  If you prefer, we will be happy to distribute a copy of your submitted draft paper; please notify Rick Beach at 
(415)494-4822 or Beach.pa@Xerox.com.
Of course, these are conference papers, and the ground rules haven't changed:  we must rely on you to consider our suggestions 
carefully, returning your revised manuscript by the deadline of April 30, 1987.  However, we believe that the extra effort 
requested will greatly enhance the value of each paper, and result in the best session of the conference.
We realize that this is only a conference presentation and consequently we accept that we cannot force you to follow our 
suggestions.  We are trusting you to read and consider our comments carefully because we sincerely believe that this effort will 
greatly enhance the value of each paper and make this the best session of the conference.

Sincerely,



Richard J. Beach
John C. Beatty
Rob Pike
Turner Whitted
enclosures: additional review, SOSP guidelines for systems papers

Addresses of graphic systems paper authors


A Programming Environment for Display Processes
    Alain Fournier
    Xerox PARC/CSL
    3333 Coyote Hill Road
    Palo Alto, CA  94304
    (415)494-4850

FRAMES:  Software Tools for Modeling, Rendering and Animation of 3D Scenes
    Michael Potmesil
    AT&T Bell Laboratories, Room 4F625
    Crawfords Corner Road
    Holmdel, NJ  07733-1988
    (201) 949-4826
    (201) 949-8989

The Reyes Image Rendering Architecture
    Robert L. Cook, Loren Carpenter, Edwin Catmull
    Pixar
    P. O. Box 13719
    San Rafael, CA  94913-3719
    (415) 499-3600