Abstract
A graphics design program for creating point-light displays of transforming 3-D objects is presented. This program was written for an Apple II microcomputer interfaced to a Texas Instruments TMS 9918A video display processor. In contrast to other 3-D design programs, it uses individual point-lights undergoing circular trajectories as a design primitive. An editor enables the user to enter and edit specific motion parameters for defining the parallel projection of as many as 16 point-lights on the screen. These parameters are then used to calculate and store in an animation list the screen positions of each point-light for each frame. Number of frames to be displayed and display rate are user defined.
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The development of this program was supported by NICHD Grant HD-16195. We wish to thank Steven Kramer for his comments on a previous version of this manuscript. Hard copies of the program are available from the same address. Please enclose $5.00 to cover the cost of a disk and postage.
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Bertenthal, B.I., Proffitt, D.R. & Keller, S.E. 3-D graphics animation program for the Apple II. Behavior Research Methods, Instruments, & Computers 17, 195–202 (1985). https://doi.org/10.3758/BF03214382
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DOI: https://doi.org/10.3758/BF03214382