# V2 Camera Debug Visualization

The camera debug visualization layer emits data-driven debug primitives for
camera systems. Runtime drawing code can bind these primitives to Unreal debug
draw calls without making the validation path depend on editor-only rendering.

## Runtime Surface

- `FV2CameraDebugVisualizationConfig` configures draw toggles, frustum depth,
  aspect ratio, primitive duration, line thickness, and debug colors.
- `FV2CameraDebugVisualizationState` carries the camera mode and spring arm
  endpoints.
- `FV2CameraDebugCollisionTrace` carries trace start, end, optional impact
  point, and hit marker radius.
- `FV2CameraDebugLookAtTarget` carries target id, location, radius, and selected
  state.
- `FV2CameraDebugPrimitive` represents frustum, line, or sphere draw commands.
- `FV2CameraDebugVisualizationEvaluation` returns emitted primitives and
  validation issues.

## Debug Rules

1. Invalid config, state, traces, or targets are blocking.
2. Frustum output emits one `Frustum` primitive carrying camera pose, FOV,
   aspect ratio, and depth.
3. Spring arm output emits a line from origin to target.
4. Collision traces emit trace lines and hit spheres when a trace hit is
   present.
5. Look-at targets emit target spheres and camera-to-target lines.
6. Selected look-at targets use doubled line thickness.
7. Draw toggles suppress their corresponding primitive groups.

## Validation Commands

Run these targeted checks when touching camera debug visualization:

```bash
python3 V2/ue/Tools/check-v2-camera-debug-visualization.py
python3 V2/ue/Tools/check-v2-camera-manager.py
python3 V2/ue/Tools/check-v2-ci-workflow.py
python3 -m json.tool V2/ue/Content/V2/Gameplay/Camera/CameraDebugVisualization_V2_Contract.json
python3 -m py_compile V2/ue/Tools/check-v2-camera-debug-visualization.py
```