combined image a b is determined by where the foregrounds 2 3 and backgrounds of the two images a and b are located on the fabric 1 and where they overlap when the two images a and b are woven together the unique phenomena of this weave structure is created the corrugated ridged effect described earlier is created by weaving alternating pairs of weft yarns located in a foreground upper plane 18 that is parallel to the face of the fabric and pairs of weft yarns located in a background lower plane 16 that is also parallel to the face of the fabric 1 each of these pairs is made up of a weft yarn 11 14 representing each image a and b the upper and lower pairs of weft yarns are woven in a different repeating pattern within each area i ii iii iv of the fabric 1 as set forth in detail below such that the ridges 20 and valleys 22 display one image a from a first angle x and the other image b from a second angle y the viewing angle x or y typically forms an angle relative to the plane defined by the fabric 1 of preferably from 20 to 70 degrees more preferably 40 to 60 degrees or most preferably 50 degrees weave structure that is common to each area i ii ii iv the.