' ==========================================================================
' RAY CASTER 3D sorta ENGINE thingymajig by Peter Cooper
' ==========================================================================
'----------------------------------------
'Translated and messed up by Erlend Rovik
'
'If Anyone Gets it to work I would appreciate
'if you mailed it to me, just so I could figure out
'where I went wrong :-)
'
'erlend@rovik.com
'e-rovik@online.no
'----------------------------------------
$TYPECHECK ON
declare sub key(key as byte)
DIM st%(0 TO 360) as integer
DIM ct%(0 TO 360) as integer
DIM a$(1 TO 10) as string
dim sa% as integer,tmp1% as integer,px% as integer,py% as integer,t% as integer
dim xb as integer,yb as integer,bx as integer,by as integer,l% as integer,k% as integer
dim x% as integer,dd% as integer
px% = 15: py% = 15: sa% = 0

a$(1) = "1919191919"
a$(2) = "9000000001"
a$(3) = "1000000409"
a$(4) = "9010005001"
a$(5) = "1020040009"
a$(6) = "9030000001"
a$(7) = "1000078009"
a$(8) = "9050087001"
a$(9) = "1060000009"
a$(10) = "9191919191"

' Peters boring _yawn_ table creation
FOR tmp1% = 0 TO 360
 st%(tmp1%) = SIN(tmp1% * .0174) * 100
' IF tmp1% MOD 100 = 0 THEN:PRINT ; ".";
NEXT tmp1%
FOR tmp1% = 0 TO 360
 ct%(tmp1%) = COS(tmp1% * .0174) * 100
'IF tmp1% MOD 100 = 0 THEN PRINT ; ".";
NEXT tmp1%

Create form as qform
 create can as qcanvas
  width=form.clientwidth:height=form.clientheight
 end create 
 onkeypress=key
 showmodal
end create

sub key(key as byte)
 IF chr$(key)="x" THEN:sa% = sa% + 3:end if
 IF chr$(key)="z" THEN:sa% = (sa% + 357) MOD 360:end if
 IF chr$(key)=" " THEN
  px% = px% + (st%(t% MOD 360) / 50)
  py% = py% + (ct%(t% MOD 360) / 50)
 END IF
 FOR t% = sa% TO sa% + 59 STEP 1
  xb=st%(t% MOD 360) / 100              'get inc
  yb=ct%(t% MOD 360) / 100              'get inc
  bx=px%                                'decimal copy
  by=py%                                'decimal copy
  l%=0                                  'reset length
  DO
   bx=bx+xb:by=by+yb:l%=l%+1
   k%=asc(MID$(a$(int(by/10)),int(bx/10),1))-48
  LOOP UNTIL k% <> 0
  x%=(t%-sa%)*5
  dd%=(1000/l%)
  can.fillrect x%,1,x%+5,99-dd%,15000
  can.fillrect x%,101+dd%,x%+5,200,2*10000
  can.fillrect x%,100-dd%,x%+5,100+dd%,k%*10000
  can.LINE x%,100-dd%,x%+5,100-dd%,0
  can.LINE x%,100+dd%,x%+5,100+dd%,0
  'problem lies here
 NEXT t%
end sub