SWI-Prolog has no built-in facilities for  graphics.  XPCE is a language
independant interface to X11 providing  a   high  level  of abstraction.
XPCE  runs  with  SWI-Prolog,  SICStus   Prolog,  Lucid  CommonLisp  and
LispWorks.  Documentation is avaliable  using   ftp  to  swi.psy.uva.nl,
directory pub/xpce.  There is a binary   of XPCE/SWI-Prolog for PC/Linux
in pub/xpce/linux.