00001
00002 c
00003 c Copyright (c) 1986,1987,1988,1989,1990,1991,1992,1993,
00004 c by Steve McMillan, Drexel University, Philadelphia, PA.
00005 c
00006 c All rights reserved.
00007 c
00008 c Redistribution and use in source and binary forms are permitted
00009 c provided that the above copyright notice and this paragraph are
00010 c duplicated in all such forms and that any documentation,
00011 c advertising materials, and other materials related to such
00012 c distribution and use acknowledge that the software was developed
00013 c by the author named above.
00014 c
00015 c THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
00016 c IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
00017 c WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
00018 c
00019
00020 subroutine outp(x,y,ier)
00021 save
00022 c
00023 c Decide on the visibility of point (x,y), and maintain the
00024 c "horizon" array. This routine is used by nxtvu.
00025 c
00026 parameter (nn = 2000, eps = 0.001)
00027 common /nxtv1/ xx(nn),yy(nn),kk,ll
00028 c
00029 if (kk.eq.0) go to 10
00030 if (kk.eq.ll-1) go to 20
00031 if (abs(xx(kk)-x)+abs(yy(kk)-y).lt.eps) return
00032 c
00033 10 kk = kk+1
00034 xx(kk) = x
00035 yy(kk) = y
00036 return
00037 c
00038 20 ier = 1
00039 end
