Section Planes

Has anyone had success implementing real time sectioning of models - eg a clipping plane that can slice a model (or better still only some actors to give control) to create an architectural section or 3D plan?

Wondering what the best approach would be for this. Any ideas?

(Have also posted in BP section as may be dev specific than Enterprise - Section Planes - Blueprint - Unreal Engine Forums)

https://forums.unrealengine.com/development-discussion/rendering/121257-how-to-create-a-section-plane

Basically it is a specific material that will react to the cutting plane (position and orientation). You apply variants / instances of this material to all objects you want to react to the cut plane.
The plane position and orientation can be read from a Material parameter collection Using Material Parameter Collections in Unreal Engine | Unreal Engine 5.1 Documentation
You need to update the material parameters with your plane live position and orientation.

The material method described above is pretty quick and easy, but doesn’t fill in the solid interior. You can sometimes fake the cap with an unlit backface color, which will give the illusion of a solid plane. Or you can also use Slice Procedural Mesh to get the cap. It’s can be computationally intensive, and doesn’t always give a nice clean result depending on the geometry, but we’ve found it useful. In my work I set it up so that when the plane is in motion I only use the material method which can run at high frame rate, and then once the plane stops moving I slice the meshes to create the cap. It’s a nice compromise.

Thanks. Will check these out. The slice procedural mesh looks heavy but the material approach looks like a good one. The blackface unlit material is a great cheat as well.

Any pointers to examples where its implemented would be amazing.

Here’s a sample material. The origin and ‘up’ parameters come from a material parameter collection that is updated via blueprints based on an actor in the scene

Awesome - thank you