Oh man, the first graphics code I ever wrote used Tektronix vector commands for drawing. It used ASCII escape sequences to specify diagonal lines on the screen, but, as I recall you could also tell it that instead of drawing a diagonal line, you could have it draw a rectangle with what would have been the endpoints of the diagonal line being opposite corners of the rectangle. These codes were supported by some VT-series graphics terminals as well as at least one dial-up terminal program on the PC back in the 80s so that’s what I targeted on my code (which was a DVI previewer for TeX running under VM/CMS).
The original Tektronix terminals (I only ever saw one once) did all screen drawing with these vector commands (think the look of the classic Asteroids game which I think may have used a similar hardware interface to the CRT display), which naturally was not especially fast for ordinary text which is why hybrids like the abovementioned VT-series terminal (I think it was the 240/340/440 that had this) ended up supplanting the Tektronix displays.
The original Tektronix terminals (I only ever saw one once) did all screen drawing with these vector commands (think the look of the classic Asteroids game which I think may have used a similar hardware interface to the CRT display), which naturally was not especially fast for ordinary text which is why hybrids like the abovementioned VT-series terminal (I think it was the 240/340/440 that had this) ended up supplanting the Tektronix displays.