GIANT SPIDERS
from Home Computing Weekly, 23rd August 1983

Have you got what it takes to face the giant spiders?

If you can't stand spiders you'll hate the man-eaters in this Spectrum
program by Clyde Bish. Why not grit your teeth and type it in?


You are on an island inhabited by large man-eating spiders who can sense your
location and close in on you. Fortunately for you, their sense of sight is
poor so if you can make them blunder into the ponds which dot the landscape
you can reduce the opposition, hopefully to nil.

This is a real-time game so if you don't make a move (use the cursor keys)
the spiders will anyway. Difficulty level 1 is quite easy. You can go above
level 3 but you won't stand a chance!

NOTE: The capital letters within quotes in lines 70, 180, 210, 1110, 1170 and
1190 are user-defined graphics. Enter these in the graphics mode.


Variables
p,q   position of man
x,y   positions of spiders
s     score (how many moves you manage)
m     spider death counter
d     difficulty level


How it works
   1-8     set graphics, reset counter and score, set difficulty level
  20-70    input and move man
  80-190   move spiders relative to man's new position, check if spiders
           reach man or fall into ponds
210-250    end of game routine
1000-1040  print field of play
1050-1090  dimension arrays, set man's start position to centre screen
1100-1120  print ponds
1130-1180  set up spider positions clear of man
1190       prints man in start position


Hints on conversion
ZX81 users could replace the user-defined graphics with available symbols;
eg. graphic A for the ponds, etc., and use the DF_CC systems variable to
detect the code of the chosen symbols in place of ATTR.
To help users of other BASICs the INK/PAPER colours are 0 black, 1 blue,
4 green, 5 cyan.
ATTR detects screen attributes at PRINT position (down, across):
32 green paper/black ink (man), 37 green paper/cyan ink (pond).
The key to the spider's tracking ability is contained in the logic in
lines 110-140.
