struct PathfindingExtraConstraint {
  enum EExtraConstraintType {
    ECT_MAXCOST,
    ECT_MINDISTFROMPOINT,
    ECT_AVOIDSPHERE,
    ECT_AVOIDCAPSULE
  };
  EExtraConstraintType type;
  union UConstraint {
    struct SConstraintMaxCost {
      float maxCost;
    };
    struct SConstraintMinDistFromPoint {
      float px, py, pz;
      float minDistSq;
    };
    struct SConstraintAvoidSphere {
      float px, py, pz;
      float minDistSq;
    };
    struct SConstraintAvoidCapsule {
      float px, py, pz;
      float qx, qy, qz;
      float minDistSq;
    };
    SConstraintMaxCost maxCost;
    SConstraintMinDistFromPoint minDistFromPoint;
    SConstraintAvoidSphere avoidSphere;
    SConstraintAvoidCapsule avoidCapsule;
  };
  UConstraint constraint;
};

IPathfinder.h