# ADR-0007: Locomotion and input layers

- **Status:** Accepted
- **Date:** TBD

## Context

The prototype is first-person: WASD walks, mouse looks, `Esc` toggles capture. Action keys were then bound on the same letters. `W` is walk-forward in the input map and wand screening in `GameManager._handle_key`. `A` / `D` strafe and also allow or deny during inspection. `Q` is polite direction and is also bound as `cancel`.

A player who walks toward a guest on a wand venue therefore fires the wand. A player who strafes during an inspection can admit or refuse by accident. The mouse cannot click UI while it is captured, and `Esc` cannot mean both "release the mouse" and "I changed my mind."

## Decision

Treat input as layers, only one of which owns a key at a time.

1. **Locomotion** (default): WASD walk relative to body yaw, mouse look on the captured cursor, pitch clamped. Short acceleration and deceleration. Gravity only when airborne; snap to the floor so the steps work. Walk speed stays around 3.2 m/s. No sprint or crouch in this pass.
2. **Modal UI** (radial, inspect, wand, radio, shift review): freeze walk and look. Recapture the mouse when the modal closes. `A` / `D` and arrows belong to the modal while it is open.
3. **Equipment and global keys** stay off the person-verb set: `G` flashlight, `L` door lock, `Tab` cycle nearby people, `R` emergency radio, `F` debug, `V` venue (debug). Wand leaves `W`; the optional shortcut is `C`.

`Esc` closes the top modal first and does nothing else. With no modal open it keeps the capture/release toggle.

## Consequences

### Positive

- Walking cannot fire wand, inspect, or admission.
- The mouse can click the action menu because capture is released while it is open.
- Cancel has one meaning when a menu is up.
- Locomotion stays first-person, which matches the body-camera framing.

### Negative

- Freeze-while-modal means the player cannot sidestep during an inspect. That is accepted for this pass.
- Power users lose `W` as wand. The wheel and `C` replace it.
- The input map and `_unhandled_input` must agree, or the conflict returns.

## Alternatives considered

- **Keep letter-key verbs on WASD:** Rejected because walk and wand already collide in the prototype.
- **Third-person or click-to-move:** Rejected; the body-camera overlay and the "you are the guard" framing depend on first person.
- **Hold-right-mouse-to-look, free cursor otherwise:** Rejected for this pass. Constant look is the default security-sim stance; the menu is the exception.
- **Never freeze walk:** Rejected because `A` / `D` cannot both strafe and step a menu highlight.