First issue:

Regarding your specific question with the four dots.

Simply set the renderer.enabled = false, that's all there is to it.

Note however that as I mention in a comment, you would never try to "cull yourself" in Unity (unless I have misunderstood your description).

Second issue:

Regarding the small spheres. I suspect you have very many in the scene. You simply can't do that. In video games (the most difficult of all 3D engineering), you just do this with billboarding. It's how say "grass" is done in a scene. You can achieve this nicely with the particle system in Unity, or other techniques. An implementation is beyond the scope of this answer, but you will have to fully investigate billboarding. Simply it's a small flat image which always faces the camera in the render pass.

Issue 2B:

Note however that sphere colliders are wonderful, and you can use as many as you want. I'm sure this is obvious from base mathematical reasons. Side tip: often folks try to "write their own" thinking it will be faster. It's impossible to outwrite the 100? person-years of spatial culling scientific research in PhysX, and moreover they use the metal, the gpu, so you can't beat it.

Issue three:

Is there a chance you're using a mesh collider somewhere in the project? Never use mesh colliders, at all. (It's extremely confusing they are mentioned or used in Unity; they only have one or two very specific limited uses.)

Issue four:

I'm confused about why you are turning things on and off. I have a guess.

I suspect you are not using more than one "stage"!

There's an amazing trick about video games when you have more than one camera. In fact you have "offscreen" scenes! So you may have players in a dungeon or the like. Off "to the side" you may have an entirely duplicate or triplicate setup of the whole thing running (you could "see it if the camera turned the wrong way") for the other cameras. (In the example you would have different qualities on the dopplegangers, coloring, map-style or whatever the case is.) Sometimes you make a whole double just to run physics calculations or address other problems.

Fascinating extreme example of that sort of thing.

In short in your situation,

对于每个摄影机视图，您可能都需要一个摄影机和大脑的整个“舞台” ！

同样，它可以是http://answers.unity3d.com/answers/299823/view.html，但这确实是日常工作。在您的整个场景中，您将看到八个并排坐着的快乐大脑，每个大脑都有自己的摄像头。在每个项目中，您将显示任何相关的项目/角度等。（显然，如果某些项目是“相同的，除了视角之外”，则可以使用“同一大脑并带有多个摄像头”：但是我不会这样做，最好为每个视图都配备一脑一摄像头）

我相信这可能是您遇到的基本问题！