title: Swift: define position of CIFilter CISourceOverCompositing inputImage
body: <p>i have a simple filter combining 2 CIImages. </p>
  
  <pre><code>let combinedFilter2 = CIFilter(name: "CISourceOverCompositing")!
          combinedFilter2.setValue(inputImage, forKey: "inputImage")
          combinedFilter2.setValue(combinedFilter.outputImage!, forKey: "inputBackgroundImage")
  </code></pre>
  
  <p>the inputImage is very small, so it looks like a view-in-view. 
  Is there any possibility to "change the position" of that smaller image? It is actually allways on the bottom-left
  I'm working with Swift 5</p>