Why did i spawn brush can't see in the viewport?

Could you possibly explain what you are expecting to see or any other details of your problem? Have you tried running the level? (I don’t think this code creates something you can see in the editor, though it depends where it is )

when i run game and execute this coda ,game view port can’t see anything , but in the editor i can see create a box brush ,and just find eight point can’t see other surface.