THE PRODUCTION NOTEBOOK

People, materials
& source notes.

We made Leather Jacket Odyssey — Director’s Cut for the 2026 Epic AI MegaJam. These are our development notes and the sources behind them. We have kept the dated test results separate from final-release acceptance.

The two creators

We’re Chai Yuntian and Tian Sang. Here is how we shared the work: Chai contributed native gameplay, recorded playback, art and animation pipelines, lighting, chapter integration, menus and validation tools. Tian Sang contributed the concept, initial project, browser editor, prototype levels, tutorials, editing interactions, typography and sound. We both worked on the chapters.

We worked across Canada and China. Our production clocks were Eastern Time (UTC−5 during the jam) and Beijing time (UTC+8). This thirteen-hour difference does not describe every Canadian time zone. Dates on day headings use Eastern Time; the timestamp control can show China’s date and time.

How the chronology was assembled

We assembled this journal from our repository history, design notes, asset records and dated validation reports at commit c9fdde21eede268e3502f39b2a4a3b015c49496b. Timestamps identify milestones or approximate work periods, not the moment every underlying task was performed. Entries marked ≈ group work around a recorded period.

The initial Unreal project and design-document commit is November 12 at 11:13 in Beijing, which is November 11 at 22:13 EST. It remains in the preparation chapter. The journal does not make a separate determination of contest eligibility. Later work is organized into the four November 12–15 production days.

• Public development narrative
• Contribution evidence and production credits
• Recorded validation and unresolved checks
• The current ten-scene route
• The structured timeline used on this website

Repository links may require repository access. The readable journal, credits and image captions are hosted here and need no login.

Images on this website

We reused images from our game and production folders for this website. The toolbox, leather title, loading portrait and spider concept were made with OpenAI image generation. They are identified as artwork or concepts, separately from native game and asset-review captures.

Development images show the game at different stages. The November 15 forest and railway images come from historical package captures; they do not validate the newest build. Web copies are resized and encoded as WebP, with no new scene content added. Image types, dimensions and original file hashes are retained.

AI-assisted production

Codex assisted code, debugging, authoring scripts and checks. OpenAI image generation supplied selected visual material; Tripo supplied meshes, textures and humanoid rigging. Blender and Unreal supported preparation, rigging, animation and integration. Two Kling videos through fal were motion references only, not skeletal animation or gameplay footage. Human direction, selection, revision and inspection determined what entered the game.

Six outdoor themes were generated with Stability AI Stable Audio 2.5 through fal.ai without reference audio, then edited into fixed loops. They are distinct from the licensed stage recording and synthesized homecoming music box. AI services are used in production; the packaged game does not require runtime generation.

Game audio acknowledgements

This website does not play or distribute the game’s audio. The game’s sourced recordings are acknowledged here for a complete account of the production.

The synthetic “Hey!” uses offline Microsoft Zira Desktop. Interaction cues, stage Foley and the homecoming music-box phrase include project-authored procedural work.

Fonts and technology

This website reuses Barlow and Barlow Condensed by The Barlow Project Authors, under the SIL Open Font License 1.1. The unmodified notices are included: Barlow OFL and Barlow Condensed OFL.

The game uses Unreal Engine 5.9 MegaJam Preview and Box2D 2.4.1. The browser authoring tool uses TypeScript, Vite, Matter.js and poly-decomp. Existing MIT-licensed skydancer and three-windline work informed cloth-cyclone and wind-ribbon presentation; native Unreal geometry implements the game effects.

Read the complete project asset and production acknowledgements ↗

What we still had to do ourselves

We spent a lot of the jam checking the results in the game: whether an asset fitted the scene, whether a collision happened where it looked like it should, and whether a player could understand the controls. Generating an image or getting a successful build did not finish that work for us.