Unfortunately, this shot isn't very clear, but what you see is the layout of the floor joist...in this case the joists are 2x4 trusses laid out on the wall in red ink, the dark rectangles are where the foam was removed and plywood screwed onto the form with a bolt in it so that the concrete would flow out to the surface of the foam and the bolt would be cast to the concrete. The use of the Simpson ICFLC is much quicker and simpler to use than bolts though.