# V2 Platform Input Prompt Icons

Phase 72.21.1.13 and input-system item 72.27.1.9 add automatic platform input
prompt icon routing for front-end and HUD prompts. The route policy maps the
active `EV2InputPlatform` and optional device tag to the existing
`Frontend.InputGlyphSwap.V2` glyph sets, so prompts show PlayStation glyphs for
DualSense, Xbox glyphs for Xbox controllers, and keyboard icons for
keyboard/mouse.

## Routes

`FV2PlatformInputPromptIconPolicy` covers:

- `PCKeyboardMouse` to `GlyphSet.KeyboardMouse.Frontend`.
- tagged `PCGamepad` DualSense devices to `GlyphSet.PS5.DualSense`.
- tagged `PCGamepad` Xbox/XInput devices to `GlyphSet.Xbox.Series`.
- untagged `PCGamepad` devices to `GlyphSet.Generic`.
- native `PS5DualSense` to `GlyphSet.PS5.DualSense`.
- native `XSXGamepad` to `GlyphSet.Xbox.Series`.
- `Switch2` to `GlyphSet.Switch2.Pro`.

## Behavior

`ResolvePlatformInputPromptIcon` accepts an active input platform, active device
tag, previous glyph platform, and action tag. It prefers device-tag routes, then
platform defaults, then keyboard/mouse fallback when no platform route can be
resolved. The resolved result carries `PromptIcons.DeviceTagResolved`,
`PromptIcons.PlatformDefaultResolved`, or
`PromptIcons.KeyboardMouseFallbackResolved` so UI view models can distinguish a
native platform switch from a fail-safe fallback.

Prompt icons hot-swap without changing the prompt layout. Screen readers use the
existing action labels from `FV2InputGlyphBindingSpec`, not controller-specific
button names alone.

## Verification

Run:

```bash
python3 V2/ue/Tools/check-v2-platform-input-prompt-icons.py
```

The checker validates the C++ API, default route table, contract, automation
spec, CI workflow, Horde gate, documentation, and TODO evidence for Sections
72.21.1.13 and 72.27.1.9.