Duck a la Carte

Transcribed from the printed issue; not yet reviewed. Read it in the PDF of the issue, page 65

Anyone who attempts the simultaneous use of two video projectors is either brave, or foolhardy, or most likely both! Peter survived the afternoon with only one brief onset of mains ripple, and the temporary loss of one blue gun (miraculously restored by the naked lady). Congratulations!

We were given a very entertaining guided tour through CISIGRAPHE-C, which has been developed over 10 years by Dyalog’s French distributor. Originally written for VS APL as a Graphpak replacement, it embodies a lot of GKS principles, and extends GKS into three-dimensional drawing. The interface from APL is by ‘external functions’ rather than an auxiliary processor, and from the demonstration it was clearly easy to use and very powerful.

Peter took us from simple line drawings (hence the ‘Duck’ of the title) through more complex shading and use of multiple windows to some very sophisticated business graphics. As with Graphpak, these are written as APL functions which unscramble ‘… gimme a piechart …’ into the necessary graphics primitives. There were some very nice features, particularly the ability to use a cross-hair cursor to enter information directly onto the graphics image.

My one reservation about the demonstration was the speed of the business graphics. Unlike the simple line drawing (effectively instantaneous) the four sample charts took 42, 90, 16, 44 seconds respectively. They were pretty complex, but even so you would be unlikely to get a serious business chart in under 30 sec; maybe this package is really aimed at the CAD/CAM user where the inbuilt 3D and fast vector drawing (an entire circuit diagram could be held in a single [n;3] matrix) would be ideal?