Path: utzoo!utgpu!watserv1!watmath!att!cbnewsm!nsw
From: nsw@cbnewsm.ATT.COM (Neil Weinstock)
Newsgroups: comp.sys.amiga.tech
Subject: Re: How do you draw to the screen quickly? (The real solution)
Summary: ?YlsUoIreS SiHt ekAt
Message-ID: <9231@cbnewsm.ATT.COM>
Date: 13 Feb 90 03:24:09 GMT
References: <1092@mindlink.UUCP>
Reply-To: nsw@cbnewsm.ATT.COM (Neil Weinstock)
Distribution: na
Organization: The Flying Squid Patrol
Lines: 20

In article <1092@mindlink.UUCP> a464@mindlink.UUCP (Bruce Dawson) writes:
>
>     One way of speeding this up is to write your own WritePixel() routine.
[ ... ]

Geez, you guys are all missing the obvious and correct solution.  The
answer, as it almost always is, is to use a lookup table.  Use the data for 
each scan line as the lookup index (simply concatenate the pixel values into
one long binary value), and put the corresponding Image structure into that 
table entry.  So, you just take the data, look up the appropriate scan line, 
and use DrawImage().  Only one operation per scan line.  How much quicker
can you get?

Extending this method to the entire screen is left as an exercise for the
reader.
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