From: Kerry Anderson <kanderson@NOFC.FORESTRY.CA>
Subject:      a BASIC program to create HPGL hexes

On Mon, 16 Dec 1996, Roberts Paul wrote:

> Thanks, Kerry.
>
> BTW, the use of a HPGL hex grid would be useful, please.
>

I kind of hacked this together a couple of weeks ago.  There's lots of
room for improvement.

HPGL is Hewlett Packard graphics language.  Most sophisticated vector
drawing packages are capable of importing these files.

I do not nor have never owned a manual so the code is a copy-cat of data
exported in HPGL.  I simply mimicked commands...

----------------------------------------------------------------------
' Kerry Anderson excellent HPGL hex generation program
'

pi = 3.1415926#

hexsize = 5 / 8

'HPGL coordinate points per inch?
pts = 1000

'Calculate sin/cos/hyp relationship wrt HPGL coordinate points
c = hexsize * pts / 2
s = hexsize * pts / 2 / SQR(3)
h = hexsize * pts / 2 * 2 / SQR(3)

'Open output file and write some preliminary stuph
OPEN "O", #1, "b:hexes.plt"

PRINT #1, "IN;"
PRINT #1, "VS32,1;"
PRINT #1, "VS32,2;"
PRINT #1, "VS32,3;"
PRINT #1, "VS32,4;"
PRINT #1, "VS32,5;"
PRINT #1, "VS32,6;"
PRINT #1, "VS32,7;"
PRINT #1, "VS32,8;"
PRINT #1, "WU0;"
PRINT #1, "PW0.350,1;"
PRINT #1, "PW0.350,2;"
PRINT #1, "PW0.350,3;"
PRINT #1, "PW0.350,4;"
PRINT #1, "PW0.350,5;"
PRINT #1, "PW0.350,6;"
PRINT #1, "PW0.350,7;"
PRINT #1, "PW0.350,8;"
PRINT #1, "SP1;"

'First centre point for Tabloid

xstart = 8.5 * pts
ystart = 11 * pts

FOR i = 1 TO 19
        FOR j = 1 TO 26
                x = xstart - 2 * c * (j - 1)
                y = ystart - (h + s) * (i - 1)
                IF i \ 2 = i / 2 THEN x = x + c
                PRINT #1, "PU" + LTRIM$(STR$(CINT(x + c))) + STR$(CINT(y - s)) + ";"
                PRINT #1, "PD" + LTRIM$(STR$(CINT(x + c))) + STR$(CINT(y + s)) + ";"
                PRINT #1, "PD" + LTRIM$(STR$(CINT(x))) + STR$(CINT(y + h)) + ";"
                PRINT #1, "PD" + LTRIM$(STR$(CINT(x - c))) + STR$(CINT(y + s)) + ";"
                PRINT #1, "PD" + LTRIM$(STR$(CINT(x - c))) + STR$(CINT(y - s)) + ";"
                PRINT #1, "PD" + LTRIM$(STR$(CINT(x))) + STR$(CINT(y - h)) + ";"
                PRINT #1, "PD" + LTRIM$(STR$(CINT(x + c))) + STR$(CINT(y - s)) + ";"
        NEXT j
NEXT i

PRINT #1, "SP0;"

CLOSE #1