Path: chuka.playstation.co.uk!news
From: Developer Support <dev_support@interactive.sony.com>
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Re: CLUT troubles!
Date: Mon, 04 Aug 1997 17:52:08 +0100
Organization: PlayStation Net Yaroze (SCEE)
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References: <33E1AB7A.1DEE@dial.pipex.com> <33E1CBFC.42D@interactive.sony.com> <33E38861.2EC9@dial.pipex.com>
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Chris Chadwick wrote:
> 
> Hi Stuart
> 
> I've attached a zip file containing a simple example to demonstrate the
> problem (I hope you get it OK as I haven't sent an attached file before :)
> It uses ClearImage() instead of MoveImage() to simplify things but the
> problem is the same.
> 
> Curiously, now that I've extracted the relevant code from my project
> for the example, I now can't seem to change *any* of the CLUT entries;
> not even the first 16 as I could before!
> 
> I'm a bit worried that you say you have no problems changing all CLUT
> entries. Perhaps I've missed something, but i can't think what.
> 
> Your info that CLUTs have to be 16 pixel aligned has cleared-up the
> 'shifted colour' problem. Thanks, I did not realize this.
> 
> I'll post this to the newsgroups as well in case anyone else is
> interested. Thanks for your quick response ;)
> 
> Chris
> 
> PS I'm using GNU development in case you need to know.
> 

OK, it seems that your CLUT is getting cached, and hence the changes are
not taking effect. The only way I can think of fixing it is if you draw
at least two different sprites, (or the same sprite with a different
CLUT location). This will clear the CLUT and reload your altered one the
next time round.

There maybe a better fix, I'll look into it.

Stuart