Why did Apple include shapes in Applesoft BASIC?
Because they were introduced with the 'Programmers Aid #1 ROM' for Integer BASIC, so it was rather natural for Applesoft to support it as well.
Shapes lack some useful features like fill and xor,
To start with, there was a XOR mode. In addition, they provided features only vector graphic could add: ...
Following a simple approach just place your code
on a C64 somewhere between $C000 and $CFFF, this RAM area is unused by BASIC and always visible to the CPU
on a C128 somewhere between $1300 and $17FF, this RAM area is unused by BASIC and visible to the CPU in Banks 0 and 15 (but not 1)
If you want to go under ROM, on both systems, C64 and C128 you would ...
There's actually two layers of activity going on here.
First, for each scanline the machine can choose both which row of pixels to scan out, and where on the row to begin. This is the basis for drawing the scenery backdrop and the track. I believe the SNES has specific facilities for doing this which are much more convenient than on the 6845-family CRTC or ...