An unimproved display tends to be confusing, the screen being composed of a large number of automata functioning in parallel. Some slight preparation will create the illusion of successive generations of evolution.
First, a single line has to be copied throughout the screen, perhaps by loading an evolutionary rule which will create the copy. Simply loading one single line throughout the bitplane, which can be done by svuline(c,p), would probably be faster.
Next, use a sweeping curtain to age successive lines, leaving the remainder untouched. Once the full screen has been swept out, uniform evolution will produce a moving display in which successive lines are a single generation apart.
One-dimensional 
automata result from using von Neumann
neighborhoods in CAM-A
, but 
or even 
automata would be
the result of introducing rules which ignored some of the states.
Whereas only 
automata can be based on Moore neighborhoods,
the possibility of taking neighbors from an adjacent line allows a
static display with a moving line of evolution, rather than the display
moving away from a static line which is the only possibility with von
Neumann neighborhoods.