Re: A82: Contrast

To: assembly-82@lists.ticalc.org
Subject: Re: A82: Contrast
From: Lars Ahlzen <lars.ahlzen@swipnet.se>
Date: Fri, 23 Aug 1996 16:04:05 +0200
Reply-To: assembly-82@lists.ticalc.org

At 10:18 1997-08-20 -0700, you wrote:
>At 06:11 PM 8/20/97 +0200, you wrote:
>>Hi!
>>I want to add a flashing effect to my game, and I figure that using the
>>contrast would be the most effective way. Does anyone have any routine for
>>this (I have ROM version 18)?
>>
>>
>>Erik 
>
>Check 82-ports.txt for the cool way to do it, there is also a mem address
>that holds the contrast, I've never messed much with this though. A nice
>flashing effect can be added by going through GRAPH_MEM and xor'ing each
>byte with $ff, which will reverse (black pixels->white, white->black) the
>screen, then do that again to restore it to it's previous state.
>
>	-Andrew

Tell me if I'm wrong, but the contrast could also be used for very smooth
and nice fade-in and fade-outs, right? I haven't seen it or tried it, but
it sounds possible to me!

Lars Ahlzen
lars.ahlzen@swipnet.se

Follow-Ups:

A82: OS-82: No APD??

From: Rob Bonstein <bonstein@mindspring.com>

Re: A82: Contrast

From: Dines Christy Justesen <c958362@student.dtu.dk>

Re: A82: Contrast

From: "Thomas J. Hruska" <thruska@tir.com>