From: Mark Phillips <umphill5 AT cs DOT umanitoba DOT ca>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Flipping an image
Date: Tue, 13 Jul 1999 11:33:30 -0500
Organization: The University of Manitoba
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> Alan Wills wrote in message <7mf2qk$nlg$1 AT rockall DOT cc DOT strath DOT ac DOT uk>...
> >void flip_image(int array[], int rows, int cols)
> >{
> >int row_count, col_count, total_pixelsp;
> >
> >  for(row_count = 0; row_count < rows; row_count++)
> >   {
> >    for(col_count = 0; col_count < cols; col_count++)
> >     {
> 
> 
> // Something like this ? (note: this is untested)
> tmp = array[row_count * cols + col_count];
> array[row_count * cols + col_count] = array[(row_count + 1) * cols - 1 -
> col_count];
> array[(row_count + 1) * cols - 1 - col_count] = tmp;
> 
> >     }
> >   }
> >}

I'm pretty sure if you do it this way you'll only want the inside loop to
go up to cols/2 instead of cols since then you'd be flipping the image and
then re-flipping it back the way it was.

mark