F/CFUTURE CITYA letter from the world you leave behindPlay the game
TRIPOTHON S1 · GAME

Build a city.
Leave a letter.

Who would you build a future for?

Give this small island a name to live up to: your child, your best friend, your future self. Over eight years, restore its streets and coastline. In 2058, your choices become a letter addressed to that person.

About 3 minutesBrowser-based 3DSix districts · eight years
ONE POSSIBLE LETTER FROM 2058

“There are trees on your walk home now. We hope you stop sometimes, just to listen to the birds.”

“This city is our gift to you. Make it yours. Leave it kinder.”

The gift is personal

Future City is a city builder about inheritance. The recipient is someone you choose. The gift is a place shaped around their possible life: a walk home in the shade, lights to read by, neighbours who notice, a coast that holds.

The letter changes with your city. It can speak of care and shelter, or acknowledge the work left unfinished. A legacy score gives you a challenge; the letter gives your decisions a human meaning.

Small island. Real choices.

Choose between urban forests, solar commons, living neighbourhoods and coastal wetlands. Funding is limited, and placement matters. A forest beside homes improves wellbeing. Wetlands do more at the coast. Foundry Hill can turn its industrial past into clean energy.

A storm arrives in 2053 and a heatwave in 2056. The city responds to the protection you built before those events. A thriving ending requires six restored districts, a legacy score of 70, and every city vital at 50 or higher.

A place for what they love

After the dedication, choose books, music, sport, the stars or the sea. A Library Tower, Bandstand, Little Stadium, Observatory or Lighthouse Garden rises in the central plaza. It becomes a personal line in the letter, glows at night, and gives the replay and recipient tour their final destination.

Watch a world change

Explore the island by orbiting the camera. Walkways, rooftop gardens, solar arrays and wetlands replace abandoned industry. A boat circles the harbour; wind turbines turn; the lighthouse and windows glow in the night view. Before / after reveals the world you inherited beside the one you made.

Switch on sound to hear wind, harbour waves and birdsong created in the browser. Birdsong grows more frequent as districts are restored. Look for a child under the trees, a reader by a lit window and neighbours on the wetland boardwalk. Sound starts off, and resident motion respects reduced-motion settings.

Send this city

The gift can arrive. At the end, choose “Send this city” or copy its gift link. The link carries your name, the dedication and the island you built. Your recipient opens their city, takes a short camera tour, and reads the letter you made possible. They can explore it, then choose “Build one for” the original sender. The new city arrives with that person’s dedication prefilled.

No account or server is required. The city is carried in the link itself. Anyone holding the link can see its names and contents. The recipient’s score and letter are reconstructed from the original sequence of choices.

The years become a letter

At 2058, watch a short replay of the island changing in the order you restored its districts. The camera orbits, night falls, and your letter appears. Skip straight to the complete letter at any time. Reduced-motion settings show it immediately. Optional read-aloud narration is available on browsers that support speech synthesis.

Save a postcard of the island and the complete letter as keepsakes.

A 55-second tour

  1. 0–10 seconds · The dedicationDedicate the city to someone you love. Choose what they love and watch their landmark rise.
  2. 10–30 seconds · The choicesBuild homes, earn funding and prepare the coast. In 2053, the storm reveals what your early decisions protected.
  3. 30–45 seconds · The world you madeComplete all six districts. See how shade protects residents during the heatwave. See the completed city at night, with its gift landmark at the centre.
  4. 45–55 seconds · The arrivalRead a personal line from 2058. See the recipient open the reconstructed gift, then discover the invitation to build one for the sender.

The game's “Record 55-second demo” control captures a complete example run from its live 3D canvas, with captions, a demonstration of gift decoding, and no audio. It restores your game afterwards. “Download asset board” exports four rendered environment views including your chosen landmark.

Made for Tripothon

The theme asks for a world as a gift. Future City turns that gift into a personal act: build for someone, then put what you chose into words they can keep.

Potential uses include short museum exhibits, classroom discussions and workshops about shared places. These are future applications of the prototype.

Tool Track = Tripo

Landmarks generated with Tripo AI

All five gift landmarks—Library Tower, Bandstand, Little Stadium, Observatory and Lighthouse Garden—were generated in Tripo using text-to-3D, H2.5. Their textures are optimised to 1024px JPEGs and their geometry is preserved. Everything else in the world is procedural.

The game loads the five locally exported Tripo models through this workflow: prompt, generate, export GLB, optimise, then load into the central plaza. Models are fitted by their bounding boxes and lit by the game’s existing scene. If a file cannot load, the corresponding procedural model keeps the gift complete.

Read the Tripo prompts and generation pipeline · Asset provenance and checksums

Submission media

Use “Download submission images” in the game to save a cover and four separate scene images. “Record 90-second submission” captures a complete guided walkthrough with captions. Both exports are generated locally in your browser.

How it is made

Original procedural 3D geometry, JavaScript, Three.js and WebGL, developed with assistance from OpenAI Codex. All five gift landmarks are generated with Tripo AI using text-to-3D, model H2.5. Everything else in the island is original procedural geometry. Three.js is used under its MIT license, included with the source. Game values are fictional rather than climate predictions. Progress stays in the current session. Choosing to share creates a link containing the dedication, sender name and city history. No account is required, and anyone holding that link can open the gift.

Created by Dhilipkumar Pandiarajan · Tripothon S1