I'm called upon to create an animation whereby a picture is assembled one pixel at a time.
It seems to me that I would take the image and apply a mask consisting of small squares from a generator and see them build the image pixel by pixel, line by line like the raster of a TV image, but I can't seem to get the formula right.
I think that after you've got a row of boxes you're going to want to add the behavior titled "Sequence Replicator" which you can find under the Behaviors Icon then Replicator>Sequence Replicator.
Go to the behaviors tab, go to paramaters and add the parameter "opacity". You can set up that parameter to make the boxes disappear one at a time. Thus making the pixels below look like they are appearing one at a time.