Copies part of the image and stores it in memory (or the clipboard, if BITINDEX is 0).
Anytime later, you can use BITPASTE to "paste" it into the image.
FMSLogo copies a rectangle starting at the turtle's position with a width of
width pixels and a height of
The rectangle that is copied is always taken horizontally and vertically, regardless of the turtle's heading.
SETPENSIZE [2 2] REPEAT 72 [CIRCLE2 100 SETPENCOLOR (LIST REPCOUNT*3 0 0) RIGHT 5] PENUP SETXY -50 -50 BITCOPY 100 100 CLEARSCREEN PENUP REPEAT 36 [FORWARD 150 BITPASTE BACK 150 RIGHT 10]