golden-camera

byManish Rohan James

A mobile app, Time Travel, MVP TECH DOC — TimeLens --- Goal AR camera. Overlay past life. Fast. Stable. Shareable. --- Platforms Android first Later iOS --- Stack Client Unity ARCore C# Assets Low-poly 3D models 1–5 MB each Backend None (MVP) --- Modules 1. Camera + AR Session Initialize ARCore Plane detection (horizontal) 2. Placement Engine Tap → place anchor Auto-scale by distance 3. Era Engine Enum: Jurassic Ice Age Early Humans Map → asset bundle 4. Creature Controller Idle animation Loop animation Simple movement (optional) 5. Overlay Engine Sky tint Fog Ground texture decal 6. Capture Module Screenshot Video recording (basic) --- Data (local JSON) { "eras": [ { "name": "Jurassic", "creatures": ["brachiosaurus", "trex"], "skyColor": "#87CEEB", "fog": 0.2 } ] } --- Performance targets FPS: 30+ Load time: <3s APK size: <150MB --- --- PRD — PRODUCT REQUIREMENTS --- Problem Learning history boring. No immersion. --- Solution AR time travel camera. See past world instantly. --- Target users Kids (10–16) Curious adults Content creators --- Core features Must-have AR camera Era switch Creature placement Capture + share Nice-to-have Info popups Sound effects --- User flow Open app → Camera opens → Select era → Tap ground → Creature appears → Capture → Share --- Success metrics Day 1 retention >30% Avg session >2 min Shares per user >1 --- Non-goals Scientific accuracy Multiplayer Backend sync --- --- SYSTEM DESIGN --- High level User device only. No server. --- Flow Camera feed → ARCore tracking → Plane detection → Anchor placement → Load 3D asset → Render scene --- Key components AR Engine Motion tracking Environment understanding Renderer Unity scene Lighting + shaders Asset Loader Local bundle load Lazy load per era --- Storage Local: Assets Config JSON --- Risks Device compatibility FPS drops Bad plane detection --- --- ARCHITECTURE --- Layers 1. Presentation UI (era select, buttons) 2. AR Layer Session manager Plane detection Anchor system 3. Domain Era manager Creature manager 4. Data Local config Asset bundles --- Diagram (simple) UI Layer ↓ AR Session Manager ↓ Placement Engine ↓ Creature Controller ↓ Renderer (Unity) --- State management States: INIT SCANNING PLACED CAPTURE --- Scaling later Add: Remote asset CDN User accounts Analytics --- Hard constraints Keep it light Avoid backend early Focus on smooth AR --- Brutal focus 1 creature 1 era working demo Ship fast.