UE Basics Thread, Talking, Learning, and Maybe More

Lots of great questions, Fantam_Mayfly, I’ll do my best:

  1. Diffuse, Albedo, Color - you’ll hear these terms and they can mean the same thing. It’s become a bit messy with terminology as techniques and technology advanced. Diffuse refers to a color map which has the AO and localized lighting (edge and cavity) incorporated into it - it is an older term for the legacy model of material systems (blinn, phong, etc.). Albedo or Color is more common now that PBR is the common application of material models. Albedo or Color would be the pure color of the material, it explains just color and no lighting (so AO and such is not integrated into it). They get used interchangeably, and tend to mean the same thing, but historically there is a recognized difference.

As we get into more interchangeable terms, remember that there is a certain point where it’s an experimental artform, using texture maps have a a standard expected use, but there are plenty of games out there that do it different than convention - something to keep in mind.

  1. Cavity and Roughness are not really interchangeable, in concept at least. Though can work well in a pinch. The material parameter “roughness” uses greyscale information to define shiny and rough interactions of light. A cavity map and roughness map are both grayscale, so the information can be accepted by the parameter. Black means smooth, White means rough, so whatever greyscale map is plugged in, will drive the roughness parameter.

This gets complicated with the addition of Specular, which is typically left as a scalar (not texture driven).

  1. Yes. Height and Displacement, so long as both are greyscale (there are vector displacement maps which cannot be used the same) are essentially the same, but there are reasons for why they are termed differently. Height is describes elevation where black is the lowest and white is highest - they can be used as a blending mask like you say, also for parallax mapping or bump offset, and some other special uses, which comes down to something I’ll explain below. Displacement maps are meant for displacement shaders, that would be tessellating a target model to then offset the vertices which can be understood as what the landscape does (it can also be seen as height).

  2. This is a common use for height information, yes. Blending textures in landscape tends to use height maps, but it can be used for more reasons.

When it comes to blending, and if we take a step back, to placement control of texture information, we think in masks. Roughness, cavity, height, displacement, AO, metallic - they are all black and white and they specify where information should occur and should not occur. So… metallic may look nice plugged into roughness; they are both just greyscale masks. Studios would prefer to use the map that is named “metallic” in the metallic slot and that’s it, don’t want to be confused.

The sky’s the limit when it comes to this area though. Some other greyscale maps, used for specific cases, involves masking for emissive control, patterns or multiple material control, thickness, sharpness, projections and light functions, voxel generation, opacity, layering, and stepped visibility control.


Question 5: Import Mesh Issue
I’ve imported a 2 static meshes into UE from Blender in fbx format. They were created together and exported at the same time. In UE, one of the meshes appears with the standard gray checked pattern on it, and it seems to function normally, I can add materials to it.

But the second one on the right in the image below, only appears as an outline. Materials can’t be applied to it as is. I can select brush wireframe and that will appear. I;ve looked at both of these texture editors and they both look the same to me.

Any idea what might be going on with it?

My guess, check the underside of it, you’ll probably see the texture there. On this guess, it would like fine in blender yet not here. Normals are reversed.

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Excellent Guess, thanks! The answer is to go back into Blender and look at the scale of the item being imported. One of the coordinates was -1.000. Changing it to 1.0 fixed the issue. :slight_smile:

That will do it. Negative scale values can affect normals.

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The proper fix is to enter edit mode, Select all, and flip normals.

For both you and ConradG, the issue continues. I fixed it for a single road piece I exported in from Blender. But I bent a piece of the road for a curve in Blender, I checked the coordiantes of the item all 1.0. it looks fine in Blender, but when i bring it in, the sides of the road appear, but the road center is flipped.

Now when you say, go into edit more, select all, and flip normals, is that in UE?
Here are some images. I can also ask in a Blender forum.

In Blender

In UE.

Question 6: I’ve got a material that produces blocky vertex painting. Is there a common reason for this? I could swear it was mentioned in one of the many tutorials I have watched, but I can’t remember what they were talking about.

I’ve been experimenting with materials and I created one by trying to morph one into another based on examples I’ve seen. I added a a third texture into a vertex blend material, and it has UV, Spectral, and Roughness elements, World Displacement, in addition to Albeto and Normal maps. Something tells me you are going to want to see the material, it’s kind of a mess, but here it is, and I realize you can’t make out much of it at this scale:

Blocky Painting, with RGB turned on you can really see the blocky nature of the painting.

The Culprit Material

No. Blender.

The mesh itself? Vertex paint.
If there’s not many vertices it will be blocky.

Landscapes only have by default 1 vert every meter.

Thanks for replying. The thing is I have a case where on the same mesh, one material looks blocky and another does not just when I start to paint. The base material looks fine until Imstart painting with another texture. These meshes have a lot of vertices. So I’m thinking there is something I did while playing with the material.

Doesn’t seem likely at a glance.

Try an engine sphere. See how that paints.

In all cases, you can reduce the effect by using an heightmap to blend between 2 layers.

This produces broken up results that aren’t linear despite the distance between verts.

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In a UE Forest scene demo I watched a talented artist piant some road meshes and after they were painted, he then tiled them end to end. He mentioned making sure they “tiled well” before painting them. I looked at that the meshes pieces I made fit together seamlessly.

He made this look easy. When I tried painting a single mesh, with the intent of tiling, I found out or it at least seemed to me that if the textures were not identical on both ends, when tiled, the differences in the textures between one end and the other really showed off that these were different mesh pieces butted end to end.

At my experience level painting a mesh with the variety of texturesto make it look like a road, and then butting identical peices together, won’t that just show off the edges if the textures were not identical at the edges?

And when I paint 6 road pieces that are butted together, it’s not as if the paint brush smoothly transitions from one mesh to the next, beause you have a mesh selected in edit mode. It seems like it would be easier to turn the 6 road pieces into one mesh for painting.
Is there something I’m missing?
I can produce an image if you think that might illustrate what I’m talking about.

Fitting togeter is one part of 4.

  1. geometry
  2. normals
  3. uv map
  4. texturing.

Painting different pieces of the same mesh requires you to select the piece of the mesh.

There’s proably no reason to.
Place the objects in engine, and use Actor Merge to join them into a single mesh so you can paint on it.

Keep in mind, this workflow illustrated by the video you shared has nothing to do with making games.

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I’m not trying to make a game at this point, just create an interactive scene.

Regarding this tutorial which is more like a tech demo, I watched him paint up a single piece of road, and then tile it out and amazingly on the opposite end of the single piece he started with, the textures all seemed to mesh as if they were identical on each end so you could see not see the seam between each piece. I ended up tiling the pieces of road, merging them, and then painting the single mesh. The other way seemed to hard, unless there is some setting with UE that will make the textures blend from one piece to the next?

Question 8: Downloading assets from Quixel, where are the static meshes? Please read and let me know if there is some obvious mistake I am making. Thanks!

This is my situation. After spending a lot of time with materials, I am ready to throw rocks and stumps into my learning project. I found what I thought was good stuff Using Quixel Bridge. So I’ve downloaded a bunch of rocks, stumps, grasses, etc. Now when it comes time to use it, I’ve picked for example a Mossy Embankment (Ti0qeiuda) and I’ve got all sorts of textures, textures allocated to LODs, but there is no static mesh associated with this.

In comparison, in the Unreal Engine Intro tutorial regarding LODs there are some static meshes with LOD in the label but they are still static meshes. I’m trying to figure out why this Mossy Embankment has no static meshes.

  • Might this have something to do with this being labeled as an assembly?
  • Even so if this assembly represents multiple static meshes, shouldn’t they be in the package?
  • The second example is a stump , it is just an asset, it does not seem to have static meshes with it either.

Now I have looked at my Quixel download setting and it might be there, it is set to the default download and I’m not seeing any place to choose to download static meshes.

I’ve included screenshots of my download settings from Quixel Bridge.

For the mossy embankment I downloaded this:

The stump:

You may have to import those assets in Unreal, then convert them to static mesh independently from Bridge. The term in Unreal is “static mesh”, whereas the term in a different application could be “mesh” or “model” or something else. Those assets are more like a brush, or a prefab…they’re still a 3D object / actor you place in the scene. However, they’re not defined as a static mesh in Bridge. Unreal puts the emphasis and technical meanings of the assets as static meshes, so try exporting or downloading from Bridge and importing to Unreal to a specified folder in the project. Then convert to static mesh.

In the dialog for it, select “Import Normals and Tangents” to maintain those used in the original asset, or select “Compute Normals” to let Unreal Engine compute new normals for them. I can’t say which is better or correct, though I would attempt to import the existing normals and tangents first. Enable “Convert Scene” too, on import, and enable Unreal’s coordinate system for the imported assets, and select Unreal’s scale units. If it’s too small, disable Unreal scale units or disable “Convert Scene”. It’s a trial/error process.

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Of course there is.
Use WPO > mask RG instead of UV.
Divided by something. Probably 1024. There’s precise math to get the texture to be mapped correctly based on the size it is.

It’s not cheap, but it will tile the texture based on position in the world, instead of using the local mesh UVs.

It’s a bit expensive, so again, something to be aware of.

No idea. Most I ever imported was a grass mesh to test it out. Using whatever plug in it comes with directly into the project.
It makes a mess of everything, but it works.

BTW, if you are trying to learn, making your own assets with your own proper texturing would probably be much more beneficial…

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Have a pleasant TDay! :slightly_smiling_face:

Apparently dragging the asset folder into UE did not bring in the .fbx files or it’s just another case of newb error. :thinking:

Ok, now I have picked them specifically, imported them and see the static meshes. When I double clicked on them I expected to see an associated material, They have no materials or textures assigned to them. There is an empty material slot and under a texture label, there are two textures listed, T_Default_Materil Grid_N and T_Default_Materil Grid_M, but if I select either of these, nothing happens.

Now I remember from another landscape tutorial that the author actually built materials (which I have) for his rocks and plants. I’ll have to revisit this.

I’d like to clarify in UE for an asset like a rock downloaded from quixel there will be textures but, no material included?

In my brief experience, I have been working with materials where I plug in textures into it at the appropriate slots, and then assign that material to an asset (static mesh), but mostly I have been working with applying materials to landscapes, versus objects like rocks/trees so this is new territory for me.

For UE I’m seeing all the textures sitting in the asset folder, but no material. From a landscape tutorial I do have 2 materials designed for rocks and plants. I can try those and until I try it, I assume I can assign the textures to the material, and then assign the material to the “material” slot in this mesh and see what happens.

As I just completed the Intro to Unreal Engine tutorial, LOD section, I’m going to let UE create the LODs so I’ll just keep the LOD0 and work from that.

Sound good, any advice (from anyone)? :slight_smile:

Update, I found what I was missing, on the LOD0 Static Mesh, double clicking on the Material Slot, pulled up the material node structure I was looking for. There is a material there. I just have to figure out which textures go where.
In this asset pack there are the following textures:

  • Albedo
  • Cavity
  • Displacement
  • Normal
  • Roughness

In the material structure there are places for texture samples to go in

  • Noise- which texture map would this be, displacement, cavity or roughness?

A texture that feeds both (Albedo?)

  • Create Base Color
  • Roughness

The one I’ve not seem before is a texture located in a grouping called “Checkerboard Divisions”, which texture would this be?

UE can be complicated, and sorry for the flailing online. Now I’m wondering if the material node structure I pulled up above was part of the downloading of this asset or if it is different part of the project that I just happened to choose. And if I am expected to use a material I made or if one is included with the download.

Maybe I’ll go eat some turkey and think about it. :wink:

You opened the material graph of the World Grid Material (shows the name of the material up in the tab’s header, after the tab for the mesh LOD0). UE is complicated sometimes, even for beginners like us when we’re trying to learn basics. Pace yourself though, if you can. It’s easy to overlook important things when jumping ahead further than you’re ready to go (i.e., you need to understand how a few things work before understanding how something a bit more advanced works).

The textures downloaded from Quixel with the 3D asset should come with it, unless you didn’t need to check boxes of texture maps, in which case I would think there might not be textures downloading with an asset. It varies as to whether you need to build the material using those textures, or if the material is pre-assembled (best to apply it to the static mesh assets you downloaded and see what it looks like to start). Even if it is pre-assembled, it may not be complete, or it may require a change in settings inside the material editor for specific purposes or whatever you’re doing with it.

Happy Thanksgiving

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Thanks for the reply, hope you had a good TDay too!

I think I have it sorted out. I’m almost certain I dragged in a folder for several assets (rocks and stumps) from megascans, after downloading them, but there was no meshes, then there were all these textures with LOD labels on them I started thinking these were somehow supposed to be meshes.

So it turns out there were .fbx files associated with these assets in those folders that had not been transferred into the project, and that there are no materials that come with them. So I used the material I made following along with a landscape tutorial which works well.

So a material must be assigned to this asset and megascans does not provide one. This makes sense in hind sight since each DCC program would have it’s own methodology to handle textures. At a minimum you could always just make a simple material and attach the associated textures to the appropriate nodes,

I’ve assumed up till now that a material simply applies textures to an entire mesh, spreading this textures or qualities over the entire object, and that any variation in the color if a rock is because those textures have the variations painted into them.

Yesterday I looked at some rock assemblies that seem to include say moss, or a log and wondered would there be separate meshes that require separate materials? Yet, the mesh seemed to be one piece. Maybe I need to look at it again. Here is an example: