Message-Id: <m0wulJl-0003EjC@fwd03.btx.dtag.de>
Date: Sat, 2 Aug 97 23:02 MET DST
To: djgpp AT delorie DOT com
References: <5rpu2i$40p$1 AT grissom DOT powerup DOT com DOT au>	
	 <33E245D5 DOT 36B8 AT stud DOT warande DOT ruu DOT nl> <33E245D5 DOT 36B8 AT stud DOT warande DOT ruu DOT nl>
Subject: Re:  URGENT! repost: palette problems, please help.
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 8BIT
From: Georg DOT Kolling AT t-online DOT de (Georg Kolling)
Precedence: bulk

Elliott Oti schrieb:
> David Orme wrote:
> > 
> > I'm displaying PCX files to the screen in VESA mode 0x101 (640x480x256, all
> > calls being VESA 1.2 for convenience). The problem is that the palette
> > either:
> > a) isn't being loaded correctly, or
> > b) isn't being set correctly.
> > 
> > This is what I'm doing:
> > 
> > byte pal[768];
> > FILE f;
> > 
> >   /* open the file and load the palette */
> >   f=fopen("file.pcx","rb");
> >   fseek(f,-768,SEEK_END);
> >   fread(pal,1,768,f);
> >   fclose(f);
>
>  
> >   /* set the vga palette */
> >   outportb(0x3c8,0);
>                    ^_______ THIS IS WHERE YOUR MISTAKE IS  ***** !!!!!
> *****
>
> >   for(i=0;i<768;i++)
> >     outportb(0x3c9,pal[i]);
>
>
> Your problem is, you're only setting the *first* colour in your palette.
> For EACH entry, from 0 to 255, you have to outportb(0x3c8, i) where 0 <
> i < 255.

That's just NOT CORRECT! The guys at IBM weren't as stupid as that when they
invented the VGA! Every VGA compatible graphics card increases the pel write 
adress automatically after receiving 3 bytes from the pel data port. This was
done for providing fast & simple palette programming