Stone Skip Go

Stone Skip is a precision physics simulation built on a Spatial 3D lake environment. PHYSICS ENGINE - Dual-input control: independent power and angle sliders - Sweet-spot mechanics: ~15-degree angle bonus coefficient for peak performance - Per-stone skip coefficients: 5 stone types with distinct trajectory characteristics - Random variance system: adds natural feel to each throw VISUAL SYSTEM - 2.5D Spatial 3D rendering: sky-to-water dual gradient with atmospheric depth - Dynamic ripple animation: Circle stroke scale-expand with 1.2s fade simulation - Moon glow and distant shore silhouettes for environmental depth - StoneShape 3D pseudo-perspective: side face, top face, specular highlight PROGRESSION - 5 collectible stone types: Pebble, Slate, Granite, Jade, Obsidian - Unlock thresholds: 4, 7, 10, 14 skips for each progressive unlock - Historical data: last 30 throws stored as JSON via UserDefaults - Real-time HUD: skip counter and power metrics during flight PLATFORM - iOS 17+ / iPhone only / portrait - 100% offline: zero network, zero account, zero permissions - Bilingual: English and Simplified Chinese - Haptic: 3-tier feedback (light per skip, success, error)