title: Python function to mirror an image vertically from R to L
body: <p>I am trying to write a python function to mirror the right half of a picture to the left half.  So far I have this code but it works in the opposite way (it mirrors from L to R)  I know it must be a few simple changes, but I just seem to have a block now.  Any help appreciated.</p>
  
  <pre><code>def mirrorVertical(source):
    mirrorPoint = getWidth(source) / 2
    width = getWidth(source)
    for y in range(0,getHeight(source)):
      for x in range(0,mirrorPoint):
        leftPixel = getPixel(source,x,y)
        rightPixel = getPixel(source,width - x - 1,y)
        color = getColor(leftPixel)
        setColor(rightPixel,color)
  </code></pre>