Pass-through shader (like transparent mask)

Can we get a shader in Cycles that will remove (more like hide/transparent) some parts of another mesh(object)? I mean some kind of mask. Imagine a forest that we want to render cutted in the middle. The simplest method that not require cutting all trees will be box with shader working as a mask. Do you have any ideas how to achieve that kind of effect?

Use an object on a Mask Layer in the render layers panel

I mean “section/profile effect”, not empty/transparent area. Object should hide everything inside but be able to show rest of (uncovered) another object - eg. half cutted orange - you see inside of orange.

there are some ways to do something like that, like using the camera’s clipping plane, or boolean modifiers, or even mixing your materials with a transparent shader, with a help of geometry:position.

Thanks for ideas but:
1st method: heh you’re right it’s probably the simplest and fastest method but with clipping we achieve also vertex clipping which means jagged edges of mesh
2nd: boolen modifiers yes it works but rather for simple objects, i have very complex objects about 0.5-2 mln triangles each (slow and jagged also)
3th: can you explain more details? if you are talking about another material (transparent) on some parts of object - its not the solution but…? :slight_smile:

Secrop thanks for that link it helps me to go in right direction! Instead of using mapping + normal I use gradient texture. Also set another math node to setup outline. Now its easy to control multiple objects by single material! :slight_smile: Nodes with description:



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