Path: utzoo!attcan!uunet!zaphod.mps.ohio-state.edu!van-bc!ubc-cs!alberta!edson!news
From: jpenne@ee.ualberta.ca (Jerry Penner)
Newsgroups: comp.graphics
Subject: Re: Hexagonal bit maps
Message-ID: <1991Jan14.073308.10370@ee.ualberta.ca>
Date: 14 Jan 91 07:33:08 GMT
References: <26275@uflorida.cis.ufl.EDU> <1942@umriscc.isc.umr.edu>
Sender: news@ee.ualberta.ca
Organization: University of Alberta Electrical Engineering
Lines: 27

In article <26275@uflorida.cis.ufl.EDU> jdb@reef.cis.ufl.edu (Brian K. W. Hook) writes:
>
>       0011111100
>       0111111110
>       1111111111
>       0111111110
>       0011111100

[ How to draw hexagonal bitmaps? ]

Well, What you do is make a bitmap that has 1 bits everywhere you
want your hexagonal pattern to show through (ie. just like your
example hexagon.)  This I will call MASK.  Your image I will call
IMAGE.  The data already on the screen I will call SCREEN.

    for each screen byte to modify
	get SCREEN
	xor IMAGE
	and MASK
	xor SCREEN	now the screen data is put where mask == 0 and
			image data goes where mask == 1
	put SCREEN

Have fun.
-- 
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    Jerry Penner	alberta!bode!jpenne	Edmonton, Alberta, Canada