From: "Michael Stewart" <mike AT reggin DOT freeserve DOT co DOT uk>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Flipping an image
Date: Wed, 14 Jul 1999 09:15:11 +0100
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To: djgpp AT delorie DOT com
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Mark Phillips wrote in message ...
>> 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, tmp;

   for (row_count = 0; row_count < rows; row_count++) {
      for(col_count = 0; col_count < cols / 2; 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.


Doh! The above code has been changed to use cols/2. Sorry about that.