Friday, May 28, 2010

Past Glories

[ Synergeo 59679, hyperlinks added, typos fixed. Note use of "tetrits" and "cubits" is quirky i.e. peculiar to this namespace; idea is alternative models of parsing volume ]

What seems clear from Steve's work on that chart is the coolness of some Great Stella or one of those (is that what he called it?), an application for viewing the various cube sizes (in his case).

You could just flip a switch and get everything in tetrits instead of cubits, with volumes computed on the fly. Of course having a "volume" requires some definite convex hull (with relative concavities) to be defined as an "having an inside" group. The notion of "facet" and/or "window" has to be there.

These conventions have been well established by now, so most of us just take for granted what a "system" is, to the point of not needing a name for one.

Synergetics makes use of this pre-existing infrastructure to swap in a unit tetrahedron on some channels, doing spatial geometry a different way. Having the spatial viewer accommodate both approaches, with a toggle or switch, is what we've been doing implicitly for years, but without much help from the software.

My rbf.py was coded in Qrays (quadrays, tetrays) at the Python level, yet in scene description language (POV-Ray's) or VRML, the convention is of course xyz. The conversion constants were worked out enough for that namespace to work. Many images were rendered.

I'm not saying toggling to Qrays and IVM volume are synonymous features. One could imagine various applications for which no vectorial features were required.

The Qrays were from David Chako, our team on Synergetics-L. I've used the term Chakovian Coordinates sometimes. The static web pages I developed during those years were about Quadrays. FoxPro Advisor published an article on my use of those in the FoxPro language. The move to Python came later.

Anyway, just getting some notes down. Our collaboration with Waterman was most intensive around there, with work in Qhull and so on, lots of insights from Gerald de Jong who did some work in Pascal. Getting some cool renderings was a breakthrough.