更新说明

AGENTS.md

@@ -170,6 +170,25 @@ SfxSystem manages: throttle (`ThrottleCount`), min interval (`MinInterval`), pri
 - `HapticSystem.Instance.Stop(uint? hapticId = null)` — stops current haptic playback
 - Supports four `HapticType`s: `Preset`, `Emphasis`, `Constant`, `Advance` (`.haptic` file)
 
+#### Device capability & fallback
+
+`HapticController.Play()` (`Lofelt/.../HapticController.cs:350`) uses a three-tier decision chain:
+
+1. **Advanced device** (`DeviceCapabilities.meetsAdvancedRequirements`) → full `.haptic` playback via `LofeltHaptics`
+2. **Gamepad** (`GamepadRumbler.CanPlay()`) → gamepad rumble
+3. **Basic OS support** (`DeviceCapabilities.isVersionSupported`) → **always falls back to a Preset**
+4. None of above → silent no-op
+
+**Advance (`.haptic` file) fallback is Preset-only** — it never degrades to Emphasis or Constant. The fallback Preset is configured via `HapticObject.FallbackPreset` in the data table.
+
+| HapticType | Advanced | Android basic | iOS basic |
+|------------|----------|---------------|-----------|
+| **Advance** | Full `.haptic` | → Preset | → Preset |
+| **Emphasis** | JSON clip | 50ms max-amplitude pulse | → amplitude-mapped Preset |
+| **Constant** | JSON clip with modulation | max-amplitude for `duration` | → hardcoded `HeavyImpact` |
+
+Emphasis and Constant have their own internal fallback chains (template-based JSON clips on advanced, raw motor patterns or Presets on basic), but these are independent direct-invoke paths — they are never used as fallback targets for Advance.
+
 ---
 
 ## Interactive Music System