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############################################################################
#
# File: koch.icn
#
# Subject: Program to demonstrate Koch curves
#
# Author: Stephen B. Wampler
#
# Date: October 14, 1992
#
############################################################################
#
# This file is in the public domain.
#
############################################################################
#
# Version: 1.0
#
############################################################################
#
#
# Comments: This program shows how Koch curves work.
#
# See the procedure 'helpmsg' for command line options
#
# Waits for a window event before closing window
#
############################################################################
#
# Links: glib, wopen
#
############################################################################
#
# Requires: Version 9 graphics and co-expressions (for glib.icn)
#
############################################################################
link glib
link wopen
global win, mono, h, w
global Window, XMAX, YMAX
procedure main (args)
local arg, nextarg
XMAX := YMAX := 700 # physical screen size
w := h := 1.0
nextarg := create !args
while arg := @nextarg do {
if arg == ("-help"|"-h") then stop(helpmsg())
}
win := WOpen("label=Koch Snowflake", "width="||XMAX, "height="||YMAX)
mono := WAttrib (win, "depth") == "1"
Window := set_window(win, point(0,0), point(w,h),
viewport(point(0,0), point(XMAX, YMAX), win))
EraseArea(win)
Fg(win, "black")
# koch_line(Window, point(0.25,0.25), point(0.75,0.25), 5)
# koch_line(Window, point(0.75,0.25), point(0.50,0.67), 5)
# koch_line(Window, point(0.50,0.67), point(0.25,0.25), 5)
koch_line(Window, point(0.00,0.67), point(0.50,0.67), 5)
koch_line(Window, point(0.50,0.67), point(0.25,0.25), 5)
koch_line(Window, point(0.25,0.25), point(0.00,0.67), 5)
koch_line(Window, point(0.25,0.25), point(0.50,0.67), 5)
koch_line(Window, point(0.50,0.67), point(0.75,0.25), 5)
koch_line(Window, point(0.75,0.25), point(0.25,0.25), 5)
koch_line(Window, point(0.50,0.67), point(1.00,0.67), 5)
koch_line(Window, point(1.00,0.67), point(0.75,0.25), 5)
koch_line(Window, point(0.75,0.25), point(0.50,0.67), 5)
Event(win)
close(win)
end
procedure helpmsg()
write("Usage: Koch")
return
end
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