24 Sep
1999
24 Sep
'99
2:24 p.m.
At 01:16 AM 9/25/99 +0100, Tony Duell wrote:
The VT55 is a VT52 with a 'waveform generator'
card. This is an option
for plotting graphs, roughly compatible with the VT105. Basically, you
can store 2 'heights' for each vertical dot-column on the screen, and
either display a point at that height (for plotting mathematical
functions) or all points below that height (for plotting barcharts). It
gave a reasonable resolution for this, with very little memory.
And thus began my entry into computer graphics, using BASIC.
It was 1979 or so, and my suburban high school had acquired an 11/03.
I tried valiantly to write subroutines on the three-person 11/03 under
what must've been MU-BASIC, to allow me to draw arbitrary VT-55 lines
and re-use dots as needed, and re-dither when more than two lines
happened in a column. I think I ran out of memory before I got
that far.
Eventually, I reworked the login system to better handle the need for
student accounts. The experience with BASIC led me to only spend
six weeks at college washing dishes and making pizzas before I landed
my first programming job, which miracle of miracles required
knowledge of MU-BASIC and other BASIC dialects.
- John