Algorythm needed for fading out windows

[William T. Dedula]

Hello All;
I am currently working on a "C" program which uses video 
windows (of various sizes) which seem to fade in and out. 
I need help in finding the right algorythm to do the job. 
Basically, I need to access a matrix of pixels within a 
video window at random BUT I only want to access each pixel 
ONE time and I want the program to exit when all pixels within
the window have been addressed. A true random number generator 
won't work since there's an excellent chance many pixels will be
accessed more than one time and I'll have no idea how long 
it would take to assure that all have been accessed. 

Although I have seen ways of doing this using tables in memory 
or similar concepts ... I figure there must be a mathematical 
function which can spit out the numbers quickly, and easily. 
Does anyone know if such a function exists and could you provide
me with as much information as you can on it ???

Keep in mind that this routine must be able to handle any size of
video window. 

video window. 


W. Tim Dedula                        Internet: 
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