The Show Computer & Network

The brain of the house and the two ways it reaches everything else.

The show computer is a Raspberry Pi (a small Linux computer) with a monitor, keyboard, and mouse at a control spot. Three things hang off it:

• An ESP32 wired to the Pi — this is the Pi's radio. The Pi hands it a message ("blackout the lab") and it speaks that out to the wireless devices in the show.
• An Art-Net → DMX link for the theatrical lights (see Lighting).
• The venue Wi-Fi (once it's set up) so the control page can be opened from a phone or laptop anywhere on site.

            ┌─────────────────────────────┐
            │   Raspberry Pi (show brain) │  monitor · keyboard · mouse
            └───┬───────────┬─────────────┘
                │           │
     Art-Net →  │           │  USB / serial
     DMX lights │           ▼
                ▼      ┌──────────┐   ESP-NOW (wireless)   games & effects
         theatrical    │  ESP32   │ ─────────────────────▶ (each also fully
          fixtures     │ gateway  │   …or RS-485 (wired) ─▶  autonomous)
                       └──────────┘

Per the platform spec, the Pi is used for "central show control, custom UI, richer video, databases/logging, deployment tooling, or network services" (spec §2, §11).

A web page on the Pi that anyone on site can use to run the show.

The Pi serves a local web page. On the venue Wi-Fi, someone with the right URL — standing at the location — opens it on a phone or laptop and can:

• Make scene changes (set a room's mood, trigger a cue, blackout, reset).
• Fire manual effects when running the show by hand.
• Have new buttons and controls added as the show grows (Orson builds/maintains the software on the Pi and wires new controls in).

Because it's plain HTML served locally, there's nothing to install and it works on any device's browser. Orson authors and manages that page and the show software on the Pi.

Fewer than ten fixtures, simple settings — just room mood plus the ability to react.

The Pi drives the theatrical lights over Art-Net (lighting control carried over the network cable) into a DMX node that talks to the fixtures. There are under 10 fixtures and we use only basic settings — this is about:

• Setting the tone in each room (a warm parlor, a cold cellar, a sickly lab).
• Centralized reaction — when one effect happens, the lights can flicker, change color, or black out in response, in that room or another.

We name moods as semantic scenes — LAB_NORMAL, LAB_GHOST, HOUSE_ON, BLACKOUT — and each maps to the DMX values behind the scenes (spec §13). We deliberately do not build a full lighting-console for this modest fixture count — lighting is a subsystem, not the organizing idea (spec §2, §13).

Devices talk in meaning, not wiring. Any device can join wirelessly or by wire.

Every device on the show speaks in meaning — messages like GAME_COMPLETE, GHOST_START, BLACKOUT — not in low-level wiring commands. That message can travel two ways, and the device doesn't care which (spec §7):

Because the meaning is separated from the delivery, any device can be wired in or run wireless — whichever suits its spot — and we can add other transports later without rewriting any game. The lighting's Art-Net/DMX is its own dedicated path; these two "languages" are for the show-message layer that coordinates games and effects.

A "scene" is a named button that does several coordinated things at once.

A scene is a named set of actions across rooms and devices — press one thing, and a coordinated set of effects fire together. That's how "one effect triggers another." Scenes are written in plain, human-readable configuration (spec §10):

scenes:
  ghost_manifestation:
    actions:
      - {target: laboratory,        command: GHOST_START}
      - {target: ghost_projector,   command: PLAY_GHOST}
      - {target: laboratory,        command: LAB_GHOST}   # lights react

The same model describes rooms, devices, capabilities, scenes, and cues — one shared picture that the operators, the running show, diagnostics, and authorized agents all read from.

A few rules keep the fancy coordination from ever becoming a single point of failure.

• Local operation first. Every game/effect works on its own. Losing the network, this computer, the internet, or any agent must never break normal gameplay (spec §1).
• Networking is additive. It adds coordination, central control, and telemetry — it does not turn independent games into a fragile connected app (spec §1).
• Deterministic at runtime. The finished show runs on plain, predictable logic with no AI in the live loop. Agents help design, configure, and service it — they don't run it (spec §1, §16).
• Safety boundary. Nothing safety-critical (e-stops, pyro, egress, dangerous machinery) rides on this general wireless/agent system — that needs dedicated safety engineering (spec §17).

• Wi-Fi at the venue — needs to be set up before the phone/laptop control page is reachable on site. (The show itself does not need it.)
• RF commissioning walk-test — before trusting ESP-NOW, walk the whole attraction measuring signal, packet loss, and latency under real interference, then choose ESP-NOW / better antennas / RS-485 per area (spec §9).
• Final fixture list — the under-10 DMX fixtures and their room assignments, to build the scene table.
• Controller build — Pi + ESP32 gateway + Art-Net node assembled; operator control page authored.