replace update() with tick() and turn()
tree5fb9a70ffa71d0a86c1c0b3e12a6eef0b7783151
-rw-r--r-- 80 .gitignore
-rw-r--r-- 1441 CREDITS.txt
-rw-r--r-- 1105 LICENSE.txt
-rw-r--r-- 262 Makefile
-rw-r--r-- 2100 README.txt
drwxr-xr-x - data
drwxr-xr-x - doc
drwxr-xr-x - scripts
drwxr-xr-x - src