Classic Computer Magazine Archive A.N.A.L.O.G. ISSUE 78 / NOVEMBER 1989 / PAGE 49

Changing Patterns

Stewart Software
11323 Blythe Street
Sun Valley, CA 91352
(213) 875-2012
800/XL/XE Disk; $35

Reviewed by Matthew J.W. Ratcliff

Changing Patterns is billed as an "art and idea generator:" But this collection of four disks presents many electronic "Spiro-Graph" simulations, many of which can be varied with keyboard inputs by the user. Hard-copy and file-save features provide some creative outlets besides the show seen on the monitor as the designs are drawn.
    Disk one contains the main program for Changing Patterns, referred to as CP. It also provides a "pre-menu" that serves as a gateway to the other disks, each of which may be booted separately as well. After presenting the title and revision screens, CP delivers the primary Changing Patterns main menu. To get an idea of what this program is about, selecting the self-generating function sends control to the "self-generating" art program, the main creativity module of the CP package. Selecting the Execute option immediately musters an interesting display of diamonds. As they are drawn, console- and keyboard-key presses change the size, shape, colors, margins and numerous other features of the design.
    Multiple columns of objects, such as hexagons, 3-D perspective boxes, octagons and lines are created with this module. The sizes and overlapping of the objects create many different, sometimes hypnotic, patterns. Certain controls applied during the creation of the art add an asymmetric twist to the screens. A particularly fascinating design can be saved to a temporary file by pressing all the console keys-Start, Select and Option-simultaneously.
    Once a masterpiece is created and saved, CP is used to load the picture and print it. Only Epson and Star Micronics Gemini printers are supported. CP defaults to "none;' instead of Epson, which requires the user to specify a printer every time the CP is run. The manual recommends using some advanced graphic-printing utilities, such as those from Alpha Systems.
    CP does a good job of generating a quick plot of a design at the top-left of a page of paper. This is ideal for folding the page lengthwise, then widthwise, to create a nice-looking greeting card, ready to be filled in by hand on the inside. This is probably the most practical use of Changing Patterns. Its ability to save screens allows the user to make use of some interesting design results in other programs, with some additional programming efforts.
    The second disk is called the Exploration Disk. It contains 34 separate short graphics programs, all tied together by a main menu. Each has a "canned routine" for creating the art. Some create intricate tile work or pictures, very much like those done with a child's Spiro-Graph. Any pattern is easily saved to disk for later viewing and plotting with the main CP module.
    All the programs are written in BASIC and are unprotected. This allows the user to backup the files, as well as study and learn from them. The programs work well overall, but I did crash one of the Exploration programs while adjusting the size of the patterns. Because all the software is in BASIC, the pattern-generation process itself can be tedious at times. The manual documents many different "macro-key" commands that are employed by the various art modules.
    The third disk is the Help disk. It is a nicely detailed tutorial that helps the user through some of the more esoteric macro functions. The manual also provides a short tutorial that contains a series of step-by-step exercises to create some pictures and help teach the menu and macro-key functions.
    The manual, nearly 50 pages, is complete, with many details. It is not well organized, however. The hardest part of using the manual is locating the right set of macro-key commands for each art generator.
    Changing Patterns is not a spectacular program, but it will provide a lot of interesting artistic interaction with the computer on those rainy days. Its inconsistent user controls provide for a bit of adventure in experimenting with cause-and-effect. When it comes time to get caught up with letter writing, the printouts make nifty little greeting cards. There are infinite designs to be discovered with Changing Patterns.


    Matthew Ratcliff, a frequent contributor to ANALOG Computing, lives in St. Louis, Missouri, with his wife and two children.