MAGI

Mathematical Applications Group, Inc

shooting recognizer

Early computer graphics pioneer.

Supported by military contracts for projects simulating equipment behavior.

They created 15 of the 20 minutes of CGI in the move Tron, including the light cycles, tanks, and Recognizers.


From ‘TRON,’ Revisited

in VFX Pro, October 09, 2000

MAGI used a modeling system called Synthavision, which built images out of simple 3D objects, such as spheres, cones and cubes. These could be added or subtracted from each other to create new shapes.

MAGI’s assignments are seen primarily in the first half of the computer-world adventure. Perhaps its most memorable scene was the light cycle sequence. “We did the light cycles with them, because they could do circles quite easily,” Kroyer said.

MAGI was based in Elmsford, N.Y. To improve its collaboration with Kroyer and Rees, a primitive modem connection was established between MAGI and the Disney group in Burbank. “Toward the end, they could load images over the phone,” Kroyer said. “You’d get these little tiny wire-frames, about the size of baseball cards.”


From A Critical History of Computer Graphics and Animation

MAGI (Mathematical Applications Group, Inc) was established in 1966 for the purpose of evaluating nuclear radiation exposure. They developed software based on the concept of ray-casting that could trace radiation from its source to its surroundings. This software, called SynthaVision (marketed by Computer Visuals, Inc.) was adapted for use in CGI by tracing light instead of radiation, making it one of the first systems to implement the later concept of ray-tracing for making images. The software was a solids modeling system, in that the geometry was solid primitives with combinatorial operators. The combination of the solids modeling and ray tracing (later to become plane firing) made it a very robust system that could generate high quality images. The graphics side of MAGI, called MAGI/SynthaVision was started in 1972 by Robert Goldstein, with Bo Gehring and Larry Elin covering the design and film/tv interests, respectively.

MAGI did an early film test for Close Encounters of the Third Kind, which was filmed on a custom film recorder (4000 lines of resolution) made by Carl Machover. The first CGI ad is attributed to MAGI – an ad for IBM that flew 3D letters out of an office machine.


From The Handbook of Ballistic Vulnerability/Lethality Analysis

Chapter I.3. — Target Description Methods: Decomposing the Task of Vulnerability Analysis

As you might imagine, developing a representation of three-dimensional shapes suitable for the task of automatic shotline intersection was the more tractable part of the problem. In the years from 1958 to 1967, employees of BRL and AMSAA devised a geometric technique that involved the combination of certain simple primitive solid volumes using the boolean operations of union, difference, and intersection. This technique was implemented as a working FORTRAN program by The Mathematical Applications Group, Inc. of ??? New York (MAGI); the program was dubbed the “MAGIC code”. In 1967 the Joint Technical Coordinating Group for Munitions Effectiveness (JTCG/ME) issued a three volume report documenting the use and operation of the MAGIC code. At the time a version of the MAGIC code was available for two of the worlds largest supercomputers: the CDC 6600 and the BRLESC.

Given the specification of a planar grid of regularly spaced cells, and a shot direction, the MAGIC code would write an output tape containing the list of components hit by the ray departing each cell heading in the specified shot direction. These tapes were dubbed shotline files; as each one took a substantial amount of computer time to generate, they were re-used and shared as much as possible. Durring this time period, there were no graphical tools available with which to view either the input or the outputs of these calculations — both input and output were spot-checked by careful manual inspection.

After some years of experience had been gained, a second generation of the MAGIC code was developed. The new program was dubbed GIFT: Geometric Information From Targets. It was designed to be upwards compatible from the original MAGIC code, while incorporating an additional variety of primitive geometric shapes, a bounding volume algorithm which yeilded substantially faster runtimes than with the MAGIC code, and perhaps most importantly, a capability for graphical output. By comparing the information from the first hit-point of each cell in the shotline file, GIFT was able to detect differences, and produce Calcomp pen-plotter drawing commands to delimit those differences. The result was a stair-step raster approximation to the profile edges of the target, drawn in ink on the pen-plotter.

The significance of this capability can not be under-emphasised; for the first time it was possible for humans to inspect the target geometry visually, rather than pouring over inch-thick stacks of numbers printed on lineprinter paper. Even still, it was an expensive and time-consuming operation to generate such a plot. In order to get a reasonable-looking drawing it was necessary to use not 4-inch cell spacing, as was typical for vulnerability analysis of the day, but 2-inch cell spacing or finer. This required several hours of supercomputer time to generate each view. Furthermore, the raster-style drawing commands given to the pen-plotter calling for innumerable very short length lines to be drawn were not of a form that made efficient use of of the pen-plotter; the resulting plots took a long time for the plotter to draw, and were the source of frequent mechanical breakdowns of the plotter.

MAGIC and GIFT were very successful programs. By automating the process of shotline file generation, they permitted vulnerability analysts to consider many more possible shots than with the earlier manual methods. At the same time, by eliminating the “bottleneck” in the shotline generating process, they created a new bottleneck: creating the target descriptions.

Sources

Mathematical Applications Group, Inc. “A Geometric Description Technique Suitable for Computer Analysis of Both Nuclear and Conventional Vulnerability of Armored Military Vehicles.” MAGI-6701, AD847576, August 1967.

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