City And/Or Photo As CPU

It's a cliche that PCB and microprocessors look like aerial views of cities, so this has that issue, but I hope I've done something new with it.

Design a city with enormously wide power cables clearly visible from the air along with junctions to those power cables which work as relays or storage capacitors, the former wired together in such a way as to implement logic gates. The top surface of everything in the city is painted with contrasting paint and a literal outline of a component which if realised in conductor plus insulator form would work as the component it actually contains.

The components are buildings with continuous stripes of contrasting colour down their walls which glow in the dark or not according to whether they are insulators or conductors. These join directly into an underslung monorail transit system which is similarly painted on top accordingly.

The entire city works as a CPU which happens to implement a program which controls various aspects of the city such as transport, utilities, stock control and logistics.

At night, the city lights up in strips rather than the usual street lighting. This enables it to be photographed aerially using old-fashioned silver compound emulsion type techniques. If the photograph is then processed in the right way, it will become a functional network of silver wires on a plate which will itself function as an identical CPU to the city itself.

There are a number of problems with this:

* I've been vague about the nature of the contrasting colours. I've mentioned glowing, street lighting and so forth, and I don't like that I've done that because it's made it too vague.

* I'm not sure whether a method really exists whereby a photographic emulsion can be completely converted to metal plus insulating gaps. I do, however, think the surface of the emulsion should be glassy rather than crystalline.

* Only one layer of circuitry is possible, unlike a conventional microprocessor.

* I'm not at all sure if silver in particular or any single layer of metal can be used to realise electronic components. I'm more or less confident it can be used to make capacitors but the rest seems a bit implausible. In particular relays, valves and transistors are all ruled out because there are no moving parts, no evacuation, no ferromagnetism and no semiconductors. Having said that, I wonder if a photography technique could be developed that deposits semiconductors, or whether that actually exists in the form of however they make chips.