imgMackay

 Create a MacKay chart spatial pattern. 

   img  = imgMackay(radialFrequency,imSize)

 The Mackay chart has lines at many angles and increases in spatial
 frequency from periphery to center.  This routine is called in creating
 the Mackay scene (sceneWindw).
  
 Examples
  img =  imgMackay;  imagesc(img); colormap(gray); axis image
  img  = imgMackay(12,256);  imagesc(img); colormap(gray); axis image

 Copyright ImagEval Consultants, LLC, 2005.