[A86] Re: vertical scrolling

To: assembly-86@lists.ticalc.org
Subject: [A86] Re: vertical scrolling
From: ComAsYuAre@aol.com
Date: Fri, 4 May 2001 22:11:46 EDT
Reply-To: assembly-86@lists.ticalc.org


The easiest method is just to move video memory to, say, $f000, and then 
display the text on the old screen (where it's invisible) and copy it to 
$f400.  Then just scroll up the entire "screen", which includes all the text 
that's in memory below the visible video memory.  Slowly the text will come 
into view, and this also means that if you have other things to add below it 
you can display them using _vputs as soon as they're needed and then copy 
them to $f400 so they can continue scrolling.  I did something very similar 
to this for a Dim-TI challenge way back when, except instead of conventional 
scrolling I was doing Star Wars-style scrolling :-)



In a message dated 5/4/2001 9:32:32 PM Eastern Daylight Time, 
Cybeross@aol.com writes:

<< This may sound stupid, but how do you scroll the text from the bottom of 
the 
 screen to the top?
 What I mean is, how do you get the text to rise from the very bottom of the 
 screen to the top (like movie credits) starting from the absolute 
bottom-most 
 pixel.  I know how to scroll the entire screen up one pixel, but how do I 
 copy the text to "below the actual screen."  And then scroll it up to the 
 visible screen.  I can't accomplish this with _vputs because it will not 
 display the text at the bottom of the screen.  Hope this makes sense.  
Please 
 help me. >>