Training Stream - Procedural Mesh Slicing - Sept 13 - Live at Epic HQ


and I are back again to help sharpen your development skills with a new feature from the 4.13 release, Procedural Mesh Slicing! Using this new ability of procedural meshes, we’re able to create tons of action-packed gameplay mechanics and visually compelling entertainment. Make sure to bring along some bandages for this cutting-edge stream.

Tuesday, September 13th @ 2:00PM Countdown]



  • Sr Training Content Creator
  • Community Manager

Feel free to ask any questions on the topic in the thread below, and remember, while we try to give attention to all inquiries, it’s not always possible to answer’s questions as they come up. This is especially true for off-topic requests, as it’s rather likely that we don’t have the appropriate person around to answer. Thanks for understanding!



1 Like

Teach us the ways.

Hoping to see that gif’s actual demo with motion controller setup.


Is there a way to “carve” around the inside of an object? Such as the ability to let’s say…use a blow torch to cut out a circle from a door?

Not with this tool, but you could do that with a destructible mesh that has “Support” pieces. There is an example of that in the destructibles content examples. This “Slice” does a clean cut across the mesh.

Not gonna use motion controllers for this one since we’re going to be showing a use of it. The technique we’ll use will be applicable to most situations and will give you the basics on how to set it up for what you need.

If you really want to you can go into the source and modify it to do that, there shouldnt be any reason this isnt possible. Id even go so far as to way im sure that it will be added at some point, this just seems like a basic first step towards that and id be disappointed if they never went further then this with it.

Can this cut through skeletal meshes?

If so, could they then go into rag doll right after?

What options/tools can we use for texturing the inside of the mesh (the “fill” faces)?

Do the pieces all handle the BP in the same way, because if you want the mesh on let’s say a button press to set to a target location, how would that work. Do the resulting pieces become different components, and if so and you would still like to place the whole components somewhere, how would you do that. Like a pizza(child/s) that is sliced, but you can still carry it all on a plate (parent), Is it possible without using the plate(parent)? Also I really hope, that in future, there will be a way to make slicing very precise, like skulpting at runtime (including the Landscape).

Thanks :slight_smile:

You use Materials to fill in the caps. Either new ones, or use the existing meshes.

There’s a way to modify or adjust the “cap” mesh in tube pieces like this?

[video]Katana - Procedural Mesh Slice in Unreal Engine 4 - YouTube

omgomgomg cutting organs and bones in half, why yes please

Edit Questions:

**Does the mesh have to be a procedural mesh, or can you use standard imported static meshes, or is there a possibility to convert static mesh into procedural mesh?

Can you use this with skeletal meshes?**

Questions regarding both this procedural slice tools and general object creation and editing in UE.

  1. Will this procedural slice tool support BSP?
  2. Is procedural slice tool only for runtime/gameplay experience or can it be used for level editing with perhaps “edit in vr” mode?
  3. Is this procedural slice tool a part of, or related to, geometry 2.0 tools?
  4. Please update us with geometry 2.0 tools, its current state and the current features plan & roadmap. Perhaps a comment or message from Ray or ?

Would it be possible to extend this to skinned meshes by operating against the pre-skinned vertices (i.e., cut in “pose-space”, then animate afterward)?

Here’s an example of using the pre-skinned vertex position in a shader in order to do masks

yes - fruit ninja!

Cool, this should be a fun stream xD

Question for the stream:

Are there any plans to add more advanced dynamic slicing/fracturing features?
For example, an option to add some noise to the sliced edges to get something like a fractured wooden piece.