Path: chuka.playstation.co.uk!news
From: "John \( QuietBloke \)" <quietbloke@btinternet.com>
Newsgroups: scee.yaroze.freetalk.english
Subject: Re: weird pixel vanishing in sprite
Date: Fri, 20 Jul 2001 00:03:19 +0100
Organization: PlayStation Net Yaroze (SCEE)
Lines: 47
Message-ID: <9j7p07$qcd3@www.netyaroze-europe.com>
References: <01c1107c$c9da4a80$4f1be4d5@pal-s-omnibook>
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Hi Pal,

OK.. dunno if this is any help.. or if Im even right.. but here goes.

You say a few pixels were missing.. they wernt by any chance missing a whole
column from either the left or the right side of the sprite ?
Again.. Im digging something out from way back in the depths of my memory
here but I seem to recall that a TIM should be created
so it fits in a whole 16 bit boudry... ie.. if you are defining a tim as 8
bit it must be a multiple of 2 pixels wide.. and 4 bit a multiple of 4.
I presume this is because the GPU works in 16bit chunks so if your TIM
doesnt fit exactly then the GPU loses the plot somewhat.

Once again.. if anyone knows Im spouting rubbish could you let me know so I
dont keep making a fool of myself :)

Hope this helps

Cheers
John ( QuietBloke )

"pal" <pal_news@hotmail.com> wrote in message
news:01c1107c$c9da4a80$4f1be4d5@pal-s-omnibook...
> I was happily coding when I noticed that a few pixels from some of my
> sprites were just missing. After a lot of checking, I still can't find out
> why. It happens always with the same bitmap data, and the same pixels.
> Whatever the coordinates of the sprite on the screen, and of the bitmap in
> vram, the missing pixels remain the same in every instance of the sprite
> drawn.
>
> The most intriguing fact is that if I scale up the sprite (say, 2*4096),
> all the pixels are here! That means that the bitmap and clut in vram are
> not damaged.
>
> I ran my proggy on two different TV sets just to check, no difference.
>
> I changed the background color (from black to dark and light grey) to
> ensure it is not an illusion...
>
> Has anyone ever met this? This is pretty weird... Any comment welcome!
> (btw, if my description is unclear, please tell me so I can try and fix it
> ;) )
>
> pal
>