From: "Jarkko Kähkönen" <Jarkko DOT Kahkonen AT mbnet DOT fi>
Newsgroups: comp.os.msdos.djgpp
References: <h9Lg4.2696$eq DOT 31448 AT uutiset DOT nic DOT fi> <3883C036 DOT E279E731 AT home DOT comNOSPAM>
Subject: Re: Calculating transparent pixels in Allegro
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Date: Tue, 18 Jan 2000 21:26:20 +0200
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

>> I use Allegro.
>> And I have a program, which calc transparency of about 16 000 pixels in
one
>> frame.:)
>> If I use getpixel, getr16, getg16 and getb16 and some other functions to
get
>> transparent color between two colors, it is too slow. I use 640x480/16bit
>> mode.


>
>Have you considered blitting the entire screen or image to a memory buffer,
and
>comparing from that directly?

How I can do it?


Jarkko Kähkönen
Jarkko DOT Kahkonen AT mbnet DOT REMOVETHIS DOT fi