The 1:1 world: Cesium and the digital twin Project 1 launch

10:00 · Brief The map the size of the empire

This course is about spatial computing, which means it is about the relationship between a model and the thing it models. That relationship has a literature, and it is older than the technology.

Borges, and the problem with perfect maps

In On Exactitude in Science, Borges describes cartographers who refine their craft until they produce a map of the empire at 1:1 — the same size as the empire, coinciding with it point for point. The next generation finds it useless and abandons it to the weather. Tattered fragments survive in the desert, inhabited by animals and beggars.

It is a one-paragraph joke about the limits of representation, and we now build that map for real, every day, and it is not useless at all. Google, Cesium, Niantic and half a dozen national mapping agencies maintain 1:1 models of the earth. Your first project is a piece of one.

So the question Borges asks becomes a live one for you: when a model reaches 1:1, what is it for? What does it let you do that the territory does not? That question is the difference between a flyover that means something and a technically competent camera move over some polygons.

Simulation and hyperreality

Once the model is good enough, people start preferring it. Baudrillard's word for the condition where the copy displaces the original is hyperreality — and you have already lived it, if you have ever recognized a city from a game before visiting it. Watch the two films below before next week; they are artists thinking about exactly this, using the same tools you are about to install.

10:45 · Guided lab Stand somewhere real

Install party, then the whole planet. We do this together because the account and key steps are where everyone gets stuck, and it is much faster to get stuck simultaneously.

1. Epic account and Unreal Engine 5.8

   Create an Epic Games account if you do not have one, install the launcher, then install UE 5.8. This is the long download — start it first and keep working while it runs.

   Exact steps

   1. Go to unrealengine.com/download, download the launcher for your OS, run the installer, and open the Epic Games Launcher.
   2. Sign in (top right). No account yet → Sign up, and verify the email before you continue.
   3. Left sidebar → Unreal Engine → Library tab → click + next to Engine versions → pick 5.8 → Install.
   4. Keep the default install options — platforms can be added later. Let the download run in the background and move to the next step now.

   Done when the 5.8 tile in Library says Launch. Start this download before anything else and keep working through the next steps while it runs.

2. Make a Cesium ion account

   Free, at cesium.com. This gives you a token that authorises the terrain and imagery you are about to stream. Keep the token valid through finals week — a dead token means a dead exhibition piece in December.

   Exact steps

   1. Sign up at ion.cesium.com/signup (email, or sign in with Epic) and verify the email.
   2. In the ion dashboard, open Access Tokens once and confirm a Default Token exists — the editor uses it automatically when you connect; you never paste it by hand.
   3. The account is free. The token dying later kills the piece — do not delete it, in December or ever this term.

   Done when the ion dashboard’s Access Tokens page shows a default token.

3. Add the Cesium for Unreal plugin

   Install from the Marketplace/Fab, enable it in Edit > Plugins, restart the editor. Follow the Cesium for Unreal quickstart — it is genuinely good and worth reading rather than skimming.

   Exact steps

   1. Epic Games Launcher → Fab (the Marketplace) → search Cesium for Unreal (free) → Install to Engine on 5.8.
   2. Open your project → Edit > Plugins → search Cesium → tick Enabled → Restart Now.
   3. After the restart a Cesium panel appears; if it doesn’t, open it from Window > Cesium. If any menu has moved in 5.8, the quickstart linked below is authoritative.

   Done when the Cesium panel is open in the editor.

4. Drop in world terrain, and look at it

   Add Cesium World Terrain plus imagery from the Cesium ion asset panel. You now have the earth. Fly around it once before doing anything useful — the sense of scale is the point of the exercise.

   Exact steps

   1. Cesium panel → Connect to Cesium ion → your browser opens → Allow.
   2. In the panel’s Quick Add list, click + on Cesium World Terrain + Bing Maps Aerial imagery, and + on CesiumSunSky so the planet is lit.
   3. Fly: hold the right mouse button + WASD; the scroll wheel changes speed, and at planet scale you will want a lot of it.

   Done when terrain and imagery stream in as you fly.

5. Georeference to a real place

   Set the CesiumGeoreference origin to actual latitude and longitude. Type real numbers, in decimal degrees. Watch what happens when latitude and longitude are the wrong way round — do it deliberately once, so you recognize it later.

   Exact steps

   1. In the Outliner select CesiumGeoreference → Details → set Origin Latitude and Origin Longitude in decimal degrees, and Origin Height around 100–300 m so you start above the ground. Campus is 27.9465, -82.4637.
   2. West longitudes are negative. Now do the swap on purpose — put longitude in the latitude box once, look at the ocean it drops you in, and swap back. That is the mistake you’ll now recognize at midnight.

   Done when the viewport opens on a place you chose, not the default.

6. Add photogrammetric buildings

   Google Photorealistic 3D Tiles give you real buildings with real geometry. This needs an API key of your own. Note that word key: this dataset is licensed, metered, and carries attribution requirements. It is not free scenery.

   Exact steps

   1. At console.cloud.google.com create a project, then APIs & Services > Library → enable Map Tiles API. This needs billing or the free trial on the account — today’s class path is on the board.
   2. APIs & Services > Credentials → Create credentials > API key; copy it.
   3. Cesium panel → + Blank 3D Tiles Tileset → select the new tileset in the Outliner → Details → Source From Url → paste https://tile.googleapis.com/v1/3dtiles/root.json?key=YOUR_KEY.
   4. Leave attribution on, and treat the key like a password — it is metered to you; it never goes in your project folder or anywhere shared.

   Done when real buildings stream in over your terrain at your coordinates.

7. Write down where you are

   Record your coordinates in your project folder, with the date and the sources you streamed. That file is the beginning of your data documentation and it will be graded.

   Exact steps

   1. In your project folder, next to the .uproject, create DATA.md: the site, its decimal-degree coordinates, today’s date, and every source you streamed — Cesium World Terrain, Bing Maps Aerial imagery, Google Photorealistic 3D Tiles — each with its licence/attribution line.
   2. It travels with the project — so it lands in your backup with everything else.

   Done when DATA.md sits next to the .uproject with coordinates, date and sources.

12:00 · Workbench Practice, unhurried

No new material. You work on your own file while I circulate — this is the hour where the technique from the guided lab stops being something you watched and becomes something you can do.

1. Find your site

   Somewhere you can defend at crit. A place you know, a place you have never been, a place that will not survive the decade. Not "somewhere with nice mountains."

2. If you fell behind, catch up here

   Installs and API keys are exactly the kind of thing that goes wrong quietly. Say so and I will come to you.

3. If you are ahead, go deeper

   Get familiar with the editor — navigation, the outliner, the content browser. Next week is camera work, and it goes better if the viewport is not fighting you.

4. Ask the AI TA anything

   The tutor on the course site is open all term for questions about how and why. It explains; you build. No agents in the work until Week 9.

1:15 · Crit / share Declare your site

Everyone puts their location on the projector and takes thirty seconds: where is it, and why that place? The answer "it looked good" is a fine starting point and a bad finishing one — we will push on it now rather than at the Week 3 crit.

Project 1 launches — Digital Twin Flyover

A ninety-second cinematic flyover of a real landscape, built on streamed terrain and photogrammetry at true coordinates. Due at the Week 3 crit. Next week is the camera; this week is the world. Full brief on the syllabus.

Homework — due before Week 2

Resources

• Cesium for Unreal quickstart — the authoritative setup path.
• Understanding the basics of Unreal Engine — work through this if the editor is new to you.
• As the Google Earth Turns (2006) · First There is a Mountain (2013).
• Borges, On Exactitude in Science, in Collected Fictions, tr. Andrew Hurley — one paragraph, posted in SpartanLearn.