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From: a447@mindlink.UUCP (Colin Fox)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Inverting Image data?
Message-ID: <4216@mindlink.UUCP>
Date: 22 Dec 90 09:49:54 GMT
Organization: MIND LINK! - British Columbia, Canada
Lines: 23

> taran@Neon.Stanford.EDU writes:
> 
> Msg-ID: <1990Dec19.184510.23035@Neon.Stanford.EDU>
> Posted: 19 Dec 90 18:45:10 GMT
> 
> Org.  : Computer Science Department, Stanford University
> Person: Lee Taran
> 
> Question about Image structs in Intuition gadgets:
> 
> If you have a one bit plane image data, and you are displaying it in
> a one bit-plane screen, there seems to be no way to get the image to
> appear reversed, ie, to use color 0 where image is 1 and color 1 where
> image is zero without inverting the image or swapping the colors.
> Is that correct or am I missing something?
> 
> ---Lee
> (taran@neon.stanford.edu)

All you have to do is 1) SetDrMd(rastport,RP_COMPLEMENT) (XOR), and then
RectFill() over your image. That will invert it (0<->1).

   --- Colin ---