function SetUpServer() {
TopHeader = "Walk through a maze"
TopDoc = "\
Please choose one of the following actions:
\
"
TopFooter = ""
srand()
}
function HandleGET() {
if (MENU[2] == "AboutServer") {
Document = "If your browser has a VRML 2 plugin,\
this server shows you a simple VRML scene."
} else if (MENU[2] == "VRMLtest") {
XSIZE = YSIZE = 11 # initially, everything is wall
for (y = 0; y < YSIZE; y++)
for (x = 0; x < XSIZE; x++)
Maze[x, y] = "#"
delete Maze[0, 1] # entry is not wall
delete Maze[XSIZE-1, YSIZE-2] # exit is not wall
MakeMaze(1, 1)
Document = "\
#VRML V2.0 utf8\n\
Group {\n\
children [\n\
PointLight {\n\
ambientIntensity 0.2\n\
color 0.7 0.7 0.7\n\
location 0.0 8.0 10.0\n\
}\n\
DEF B1 Background {\n\
skyColor [0 0 0, 1.0 1.0 1.0 ]\n\
skyAngle 1.6\n\
groundColor [1 1 1, 0.8 0.8 0.8, 0.2 0.2 0.2 ]\n\
groundAngle [ 1.2 1.57 ]\n\
}\n\
DEF Wall Shape {\n\
geometry Box {size 1 1 1}\n\
appearance Appearance { material Material { diffuseColor 0 0 1 } }\n\
}\n\
DEF Entry Viewpoint {\n\
position 0.5 1.0 5.0\n\
orientation 0.0 0.0 -1.0 0.52\n\
}\n"
for (i in Maze) {
split(i, t, SUBSEP)
Document = Document " Transform { translation "
Document = Document t[1] " 0 -" t[2] " children USE Wall }\n"
}
Document = Document " ] # end of group for world\n}"
Reason = "OK" ORS "Content-type: model/vrml"
Header = Footer = ""
}
}
function MakeMaze(x, y) {
delete Maze[x, y] # here we are, we have no wall here
p = 0 # count unvisited fields in all directions
if (x-2 SUBSEP y in Maze) d[p++] = "-x"
if (x SUBSEP y-2 in Maze) d[p++] = "-y"
if (x+2 SUBSEP y in Maze) d[p++] = "+x"
if (x SUBSEP y+2 in Maze) d[p++] = "+y"
if (p>0) { # if there are unvisited fields, go there
p = int(p*rand()) # choose one unvisited field at random
if (d[p] == "-x") { delete Maze[x - 1, y]; MakeMaze(x - 2, y)
} else if (d[p] == "-y") { delete Maze[x, y - 1]; MakeMaze(x, y - 2)
} else if (d[p] == "+x") { delete Maze[x + 1, y]; MakeMaze(x + 2, y)
} else if (d[p] == "+y") { delete Maze[x, y + 1]; MakeMaze(x, y + 2)
} # we are back from recursion
MakeMaze(x, y); # try again while there are unvisited fields
}
}