Polytope de Montréal by Xenakis
Polytope de Montréal (1967), Xenakis, pg. 204.
…webs, created out of more than 200 steel cables ranging from 30 to 31 meters in length, in turn provided the strutter on which 1200 light flashes were attached. It was not possible to computerize the light show and this proved to be the greatest technical challenge of the final realization. Automation was ultimately attained by creating a command film where each state of change (the critical fusion frequency) was first drawn on millimeter paper and then photographed onto a film frame with 1200 spots representing the same number of flashes. This film was then projected onto a light sensitive board that in turn activated a specific light. ~Iannis Xenakis, Music and Architecture.