Fighting Game · Guides & deep dives

V2 Camera Collision Avoidance

minimum camera distance, collision buffer, pull-forward and recovery speeds, transparency distances, minimum opacity, enable flags, aim behavior, and mode blend time.

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The camera collision avoidance layer resolves camera placement after a desired camera has been computed. It prevents clipping through blocking geometry by moving the camera in front of the nearest obstacle, and it emits transparent near-clip occluders for geometry close enough to the camera to need faded rendering.

Runtime Surface#

  • FV2CameraCollisionAvoidanceConfig configures probe radius, near-clip radius, minimum camera distance, collision buffer, pull-forward and recovery speeds, transparency distances, minimum opacity, enable flags, aim behavior, and mode blend time.
  • FV2CameraCollisionAvoidanceState carries the pivot, desired camera location, current camera location, camera rotation, base camera mode type, and FOV.
  • FV2CameraCollisionAvoidanceObstacle carries deterministic obstacle data: id, blocking flag, transparency support, closest point, distance from pivot, thickness, current opacity, and whether the camera starts inside the obstacle.
  • FV2CameraCollisionAvoidanceTransparentOccluder returns the resolved near-clip fade target for each transparent occluder.
  • FV2CameraCollisionAvoidanceEvaluation returns desired, target, and adjusted camera distances, adjusted pose, clipping and transparency flags, transparent occluders, mode spec, and validation issues.

Clipping Rules#

  1. Invalid config, state, delta time, or obstacle data is blocking.
  2. The desired camera vector defines the camera corridor from pivot to desired location.
  3. The nearest blocking obstacle inside the desired corridor shortens the target distance to DistanceFromPivot - CollisionBuffer, clamped by MinCameraDistance.
  4. When the camera starts inside geometry, the target distance resolves to the configured minimum distance.
  5. Pull-forward and recovery speeds move from the current distance toward the target distance deterministically.
  6. NoClearCameraSpace is reported when blocking geometry leaves no clear distance beyond the configured minimum.

Transparent Near-Clip Rendering#

When bEnableNearClipTransparency is enabled, transparent obstacles near the adjusted camera generate TransparentOccluders. The fade is strongest at or inside TransparencyFullDistance and blends back to each obstacle's current opacity by TransparencyStartDistance. Designers can feed TargetOpacity into material parameter collections, component custom depth rules, or actor fade systems without changing camera placement.

Camera Manager Export#

EvaluateCameraCollisionAvoidance fills ModeSpec using id camera.collision_avoidance. BuildCameraCollisionAvoidanceMode can export a custom id, priority, and active flag while preserving the state's base mode type.

Validation Commands#

Run these targeted checks when touching camera collision avoidance:

bash
python3 V2/ue/Tools/check-v2-camera-collision-avoidance.py
python3 V2/ue/Tools/check-v2-camera-spring-arm.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/CameraCollisionAvoidance_V2_Contract.json
python3 -m py_compile V2/ue/Tools/check-v2-camera-collision-avoidance.py