The color/3D Atari vector games used the Analog Vector Generator, which used op-amps to trace smooth lines of arbitrary length and angle on the screen. It also seems to fall out of calibration as the years go on, which is why you see a lot of Star Wars and Tempest machines with jittery images.
If you really want to get esoteric and hackish, the Cinematronics vector games of the era had NO microprocessors in them at all. It's all bit-sliced TTL gates and EPROMs to hold the object code. Wrap your noggin around that one.
About the same time I was playing too much Atari Star Wars I was also using HLH Orions on my CS course - the early models had bitslice based CPUs and had user programmable microcode:
More information on the Atari vector hardware, written by one of the original engineers, is here: http://www.jmargolin.com/vgens/vgens.htm