raytracing - how to make object hidden, but still available for rendering?


I was testing the archviz raytracing scene and I come to a problem I was not able to solve, I would like to look inside of the room from top, keeping the light coming in only through windows. But when I hide the ceiling mesh, light is going through ceiling as if there was no mesh anymore (but it is just hidden). What I would like to achieve is that when I hide mesh, it is hidden for the camera, but the light solver still works with the ceiling mesh and therefore it wont let any particles through ceiling. Works when baking lights, I can hide the mesh, but when baking the lightmass bakes the hidden mesh included. Is there any solution, like near clipping plane, to be able to see from top, but to hide mesh on camera. Is there a way how to make clipping plane into an actor? (plane would be not locked on the camera, but rather on actor) and therefore I would be able to make sections?


you’re after “hidden shadow” in the lighting tab of the object, then when you set the object visibility to off, the shadow remains
Edit: not sure if this works with RTX although i assume it does. still waiting on my 2080ti in the mail >>