Edit collision shape for static mesh in UE4

Is there a way to edit collision shape within editor?

I’m importing stair meshes, and default collision shape is off, regardless of the settings. Basically, I’d like to move individual vertices on collision shape.

As far as I know, I can remove collision, create collision, but I haven’t found a way to modify it.

Am I missing anything?

You can scale, rotate and move entire collision hulls in the Static Mesh editor. However you can not move individual vertices like you wanted to. The only way to effect individual vertices is to create the collision in a modeling program like Max, Maya or Blender and then import that into UE4 along with your static mesh.

Hmm, alright then.

I found this reference: FBX Static Mesh Pipeline in Unreal Engine | Unreal Engine 5.3 Documentation

I guess the question is solved.

Hi there- in case it’s of use, you’ll be able to do this with our “ProBuilder” tool in the near future. Hope this helps!
https://forums.unrealengine.com/showthread.php?87411-ProBuilder-for-Unreal-Official-Development-Thread

I’m aware of probuilder (after reading this bsp thread anyway) and I’ve been eyeing ue4 probuilder thread too, however I would really like to have some time estimates. For example, how “near” is that “near future”.

Also, AFAIK probuilder would be more suitable for brush-based level building, not for collision. I doubt that you’ll be able to edit collision (with probuilder) for single static mesh so all the other instances of this mesh will be using the same collision shape.

Thanks, I see we need to be more clear with our time estimates. I’ll go in and edit the main post to make that obvious. At this point, estimating 1 month till we have a useable, basic version, 3 months till complete product.

About brush-based, perhaps I need to make that more obvious as well- assuming too much :slight_smile: PB is very different from brush-based geo modelling, it’s much more akin to 3DS Max/etc, but heavily simplified, of course. So, editing a collision mesh would be very simple, and if you edit as an instance, would certainly propagate to all other instances of the mesh. So yes, you could edit once, and be done.

Although, maybe this is overkill- been looking into bringing our “QuickEdit” tool into Unreal, maybe we should push that forward?
procore3d.com/quickedit

Imo, there’s not much point in that, IIRC unreal already has static mesh editor.

There’s a need for quick level prototyping tool, not in-engine editor.

It is 2015, so I expect to be able to create unfurnished textured 16 story building in 3 minutes, then go through every room and every wall and assign materials where I need them, sims house-building style, then move walls where needed. And when “industry standard” engine can’t do something like that out of the box, it is very disappointing.

Hmm, I’m afraid I don’t understand entirely- but it sounds like we have different workflows anyway! :slight_smile: Thanks for the interest, whether or not it ends up useful to you! :slight_smile:

It means that I would love to have a tool where I could create a cube, assing tileable material to each side, then drag sides to turn it into floor-sized shape, then punch in the windows/interiors then duplicate it x times to make a building. It is sketchup-like or sauerbraten-like workflow (sauerbraten is a videogame).

The main issue here is that this kind of workflow requires automatic generation of tileable texture coordinates - you can’t really place a box and scale it, you need a brush or geometry that regenerates tex coords. Judging by the videos I saw probuilder can handle that.

Static-mesh based workflow could also be streamlined to allow user to create rooms, drag their walls and make engine build the walls from static meshes, but that’s different story.

Oh, I begin to see- though it does sound like what you want, is exactly what ProBuilder does, and does with standard static meshes. (or dynamic, should you want them to be so)

In PB, you are always building just a standard, regular, mesh. No BSP/brushes/etc.
You can, as mentioned simply create a cube (or other shape, including procedural like stairs/arch/etc), assign materials per-face (“side”), then drag the sides into any shape. You can continue to make windows, doors, extrude, duplicate, etc. All this, and more, no problem in PB.

At the same time, yes, the UVs are being auto-generated to tile cleanly. You can also edit that auto-tiling (ie, offset, rotation, scale, flip, etc), similar to the brush-based methods.
Additionally, you can dig in and do a full UV Unwrap with PB, if you like. You can also swap between manual UVs (unwrap) and auto UVs (brush-style, auto generated), on the fly, per-face.

Correct me if wrong, but I think PB does exactly what you are asking for, and then some? :slight_smile:

Texture generation seems to be behaving in the way I need it and I can do what I have in mind with PB.

However, as far as I know, pro builder doesn’t do CSG (constructive solid geometry). Having CSG would’ve been perfect, but that would be a tall request, because that requires realtime boolean operations in 3d. That kind of thing can be done on axis-aligned cubes scenes, but when you throw rotations and random shapes into mix, it becomes much more difficult. The CSG would be a good thing because in case of CSG you can duplicate and copy-paste subtractive shape to carve out large repeated patterns in other shapes, like carving out rooms in a single “building” primitive.

You might want to investigate that as possible feature in the future.

Actually, yep, ProBuilder does have CSG (we call it Boolean in 3DSMax/etc land). It’s in the “Expirimental” menu (Tools > PB > Exp > Boolean). It generally works fine, but we want to really finesse it before we call it complete.

No problem to do this in real-time, unless you have a really high poly count object (which wouldn’t be PB stuff anyway).