是否可以通过line trace获得hit character 的 uv?

想通过line trace获得hit,然后通过FindCollisionUV获得 character skeletal mesh的材质UV
但是似乎skeletal mesh hitresult的faceindex 始终为-1 ,只有static mesh才有效?
已经设置了bReturnFaceIndex and bTraceComplex to “true” in FCollisionQueryParams .

does the mesh itself is configured for complex collision queries ? (e.g. not using “use simple as complex”)