This is Version 1.1 of a non-recursive algorithm to draw a dragon curve.

The way how the curve is drawn is described in paperfolding.pdf.

It uses tgi.h to plot the curve, so it only runs on platforms supporting
tgi and at least 320x200x2 resolution.
The short assembler routine should run on any 6502 compatible processor,
so if you want to get it run on some other platform, you have rewrite only
the draw functions.

To compile the program do not forget to link the machine code:

cl65 -t c64 -Ois drachen.c testbits.s
cl65 -t c128 -Ois drachen.c testbits.s
cl65 -t apple2enh -Ois --start-addr 0x4000 drachen.c testbits.s
cl65 -t atari -Ois -Wl -D__RESERVED_MEMORY__=0x2000 drachen.c testbits.s

Monte Carlos 

Apr 2006