My uncle had a Commodore Plus/4. A really lousy computer, even for those days. It had very little RAM and there were hardly any games for it. But my uncle also had a manual for it and in it there were some programming examples in BASIC. The chapter with graphics programming interested me the most.
I can't remember the details, but you had to program geometric shapes and put them together somehow. Shapes like circles, squares, triangles and so on. You had to enter start and end coordinates, radius of the circles, frame and fill colors, etc. Basically like an ancestor of today's SVGs, but without the portability of it. So I see this as my first steps in graphics programming.