Re: A82: Greyscale Mentioned?

To: assembly-82@lists.ticalc.org
Subject: Re: A82: Greyscale Mentioned?
From: Jkhum98@aol.com
Date: Wed, 28 Jul 1999 13:28:22 EDT
Delivered-To: assembly-82-outgoing@towerguard.unix.edu.sollentuna.se
Delivered-To: assembly-82@lists.ticalc.org
Reply-To: assembly-82@lists.ticalc.org


In a message dated 7/28/99 11:54:09 AM Central Daylight Time, 
ADAMMAN106@aol.com writes:

> In a message dated 7/28/99 1:34:19 AM Eastern Daylight Time,  
> Jkhum98@aol.com writes:
>  
>  > Ive read that ADAMMAN is using Greyscale for Defiance, and Jeremy is 
using 
>  >  it for AgentX... Would y'all mind posting any source code you have on 
that?  
>  
>  Jeremy posted his source on his website.  Though I haven't really looked 
at 
>  the source, I tried out his test programs and it seems to be better 
quality 
>  grayscale than mine.  Sometime I will probably analyze it and see what the 
>  differences are, but I'm pretty sure we both use interrupt speed to vary 
the 
>  quality of the grayscale.
>
>  > I would assume the greyscale interrupt technique is very similar to what 
>  > the 83 can do, and I have been experimenting alot with greyscale for the
>  > past week, and a month ago before this, yet I cant get it to be of any 
good 
>  > quality... I got perfect greyscale on VTI, but that means nothing since 
it 
>  > doesnt Emulate the hardware in any similar way... Please inform me about
>  > any new techniques there are... :)
>  >  
>  >  Jason_K
>  
>  I basically ported the interrupt stuff from the 85, and used a routine 
given 
>  to me by Dines to put the images on the LCD.  It's not the fastest 
routine, 
>  but it seemed to give better results than faster routines.  Then so the 
>  grayscale doesn't look like crap, you need to use port 4 to change the 
>  interrupt speeds...unfortunately the quality that different speeds give 
> seems 
>  to vary greatly on each calc, and of course battery power is a major 
factor. 
>  
>  Grayscale on the 82 is extremely sensitive to any changes that are made.
>  I haven't even attempted to implement it into Defiance yet, and I hope and 
>  pray that it will work well.
>  
>  ~Adamman
>  

May I have the URL to Jeremy's Website...?  

With the interrupt speed, do you alter that within the interrupt, or before 
you enable it? And do you change the interrupt speed to vary the shades of 
grey, or do you just use a ratio of altering the bit planes in the 
interrupt...?

You say you have a routine to put Images to the LCD? I thought the method was 
to use two 768 byte Bit-Planes, and copy those to the LCD... I understand how 
that would be slower than Direct LCD Communication, but I dont know how to 
keep track of the images and stuff... =P

Jason_K

Follow-Ups:

Re: A82: Greyscale Mentioned?

From: Jeremy Wazny <j.wazny@ugrad.unimelb.edu.au>