Rendering a solid surface on a Primitive Mesh clipped by a plane

[10dimensions]

I have several primitive objects enclosed by one another in my scene. Mostly, BoxGeometry and Cylinders.
And I have clipping planes in multiple axes (xy, xz, yz), which are dynamically moved by the user.
When a clipping plane intersects an outer mesh, the vertices outside the normal plane are removed automatically.
But at the same time, since the outer geometry is hollow, this in turn shows other meshes which are contained inside to be visible.

I tried using a fragment shader technique which has been discussed in the following threads, but without any success.

How to render clipped objects as solid objects with predefined color?

Hi, I am reffering to this method stackoverflow to easily let clipped objects appear capped by changing the fragmentShader before it compiles. (I changed to this method rather than making stencils because I have multiple Objects with different capping-Colors, where I have got lost with all the stencilBuffers and renderOrders.) It works well with: material.onBeforeCompile = function( shader ) { shader.fragmentShader = shader.fragmentShader.replace( '#include <output_fragment>', …

Capping clipped planes using stencil on a BufferGeometry()

Hi. I am a bit of a novice when it comes to coding on three.js so I wanted some help on this: I am working on a project that requires clipping planes on a geometry and then capping up the cut portion. I saw many examples and questions and found this to be the closest to what I need: https://threejs.org/examples/?q=stenc#webgl_clipping_stencil . However I tried repeating the same for my project using the code below (but it does not create the cap) . Am I missing something ? this.partGroup = n…

Have attached a jsFiddle to better understand the problem as well.

Edit fiddle - JSFiddle - Code Playground

Any help would be greatly appreciated. Thanks in advance.

[drcmda]

this is quite hard, there is a way using clipping planes and stencils but imo in the end the code was more complex than just using csg. clipping caps - CodeSandbox

i had a small demo using clipping + stencil, but don’t seem to find it no longer. :-S