Path: chuka.playstation.co.uk!news
From: richard.cutting@virgin.net (Richard Cutting)
Newsgroups: scee.yaroze.programming.2d_graphics
Subject: Re: How do I manipulate Pixels?
Date: Sat, 08 Aug 1998 00:08:46 GMT
Organization: PlayStation Net Yaroze (SCEE)
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On Fri, 07 Aug 1998 21:18:18 +0100, James Russell
<James_Russell@scee.sony.co.uk> wrote:

>Chris Searle wrote:
>> 
>> As and example how would I rereate TV static, ie randomly setting each pixel
>> as black or white ( rand()%2 , on or off). Please, please give me source its
>> all I understand!
>
>
>You can use the LoadImage and StoreImage commands to access VRAM memory from main memory. It
>probably isn't the most efficient way to do this, but by duplicating areas you could get a quite
>nice static effect (colour cycling would be better).
>
>Cheers,
>
>James
>
>-- 
>== James_Russell@scee.sony.co.uk                +44 (171) 447-1626
>== Developer Support Engineer - Sony Computer Entertainment Europe
>
>Remember, Subaru spelled backwards is U-R-A-BUS.

I was playing with this sort of thing myself recently. The way I found
to muck about at the pixel level was something like the following (
and no it's not optimised .... ).  This is for a 320 * 256 screen and
doesn't take double buffering into account....

// Code starts

unsigned long screen[320*256];

RECT scr;

register int i;

scr.x = 0;
scr.y = 0;
scr.w = 320;
scr.h = 256;

for( i = 0; i < 320 * 256; i++ )
{
	screen[i] = rand()%2;
}

LoadImage( &scr, screen );

// Code ends

Obviously it can be a lot more efficient.........But you should get
the idea.......

Richard.
http://www.netyaroze-europe.com/~rcutting