How can I make a shader that makes the intersection of two 3D objects transparent?

Question

I need a shader that can make intersection of two 3D objects transparent. I know how can I make two sprites intersection area transparent. I use stencil buffer in shader. But I don't know how I can do this in 3d objects. Please help me , thank you!

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Answer 1

you can work with 3 objects, and use the stencil buffer to do the effect.

One of the objects will have

Stencil{
   Ref valueA
   Comp aways
   Pass replace
}

the second:

Stencil{
   Ref valueB
   Comp greater
   Pass replace
}

the third:

Stencil{
   Ref valueB
   Comp less
   Pass replace
}

the trick is to put the second and third object in the same position