From: Flenser <flenser AT cs DOT iastate DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: ANDing bitmaps under allegro
Date: Wed, 03 Nov 1999 10:19:31 -0600
Organization: Iowa State University, Ames, Iowa, USA
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To: djgpp AT Delorie DOT com
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Reply-To: djgpp AT delorie DOT com

I am running at 8bpp. Basically, I have a bitmap containing an image,
and then another with a silhouette of that image in white on black. If I
were to AND them together, it would only draw the parts of the first
image that correspond to the white parts of the mask. I've tried this in
Paint Shop Pro 5, and it works nicely. I guess this would mean
performing a binary AND on the color of each pixel in the images.

gradha AT iname DOT com wrote:

> Flenser <flenser AT cs DOT iastate DOT edu> wrote:
> > I need to AND two bitmaps together, and assign the result to a new
> > bitmap. Does anyone know how to do this?
>
> But what do you mean by ANDing? Do you mean merging to colors at
> 50% each, taking the bits of one colors and anding them bit to bit,
> add the colors, or the bits of the colors?
>
> And then, what color depth are you talking about? Because bit-anding
> on 8 bpp is different than on other resolutions, since the "color"
> is in fact an index to a palette containing the color...
>
> Grzegorz Adam Hankiewicz - gradha AT iname DOT com
> Gogosoftware - http://welcome.to/gogosoftware/
>
> "I gotta be me; I'm too good to be anyone else." - Garfield.