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A newbie question about texture making using Normal+Roughness maps.

Hello community! I just started following the “Unreal Engine 4 - Materials” lessons on YouTube (from Epic Games), and attempted to make my own steps in creating some. But then I stumbled into a problem where the tutor guy got some pretty neat result: tut_mat_sshot2.jpg

While though I was doing everything the same of what he was doing and explaining, yet I ended up with this in result: tut_mat_q2.jpg

As you can see there is a big difference in the normal and roughness maps affecting the result scene (actually the difference is also clearly noticeable in the texture node editor’s 3DViewport). I used the scene lights and the shadow settings by default as it was recommended in the beginning of the tutorial. Later on though I made an attempt to play with the different illumination and shadow settings (like making the MeshActor movable and turning on the dynamic shadows, ILCQ volume on, adjusting and placing additional light sources, e.t.c.), but unfortunately with no better result.

Here are the texture nodes set, mine is exactly as his: tut_mat_qp.jpg

In fact, either of maps in my setup are working and affecting the rendering scene. But the result a so much different to the tutorial example, so it makes me feel like there is something horribly wrong in my approach. I would very appreciate if you would suggest or explain me the issues of the problem and how it could be possible to fix that!

Just a guess, but I think your lerp node is backwards. Switch the Const A and Const B numbers. You might be unintentionally reversing the roughness texture, causing it to become a lot more matte than the tutorial.

Thanks for the input, Daniel! I thought it so in first, but i believe this is not the root of the problem, as “A” is actually a black channel input, and the floor crevices are initially painted -> black. So the higher roughness is would be that what is needed for “A”. Today i made an attempt and completely redrew the normal map from scratch with a lot of adjustments in my way on. Here is what it made the material look like: b3ee8fcb7fd30114f6ba640c81ec73e2de2bb87d.jpeg

While it’s looking cool to me, it is actually not. Because of the way i made this new normal map it is exceeding the image information load over the common samples of mapping. I would say it is loaded to the edge of the normal mapping limits. Also, the preview in 3Dport in the texture editor is not good at all. It is not as it should be with the proper mapping really.

Oh and btw, i have another question, so i would ask it on the opportunity! Is there an easy way to put my own adjusted roughness map into the texture editor? And what would be the best way for preserving it - store the map data into the main texture Alpha, or loading it as a separate node? Wondering if there an actual way to have the roughness map loaded separately into the tex.editor and then having it connected to the Lerp’s Alpha input.

Honestly, just keep your roughness texture as its own separate map. Here’s how I normally do it if vram is really a concern:

Diffuse/Albedo texture in RGB, no alpha
Normal texture in RGB, no alpha, at half or quarter resolution, whatever I can get away with (normal maps take up more vram)
Detail normal in RGB, no alpha, at very low resolution (64x64, 128x128, 256x256)
Roughness, Alpha, and Metallic (or AO if no metallic or alpha map in its place) all in one RGB texture with no alpha channel, one channel each which then gets separated out in the material editor.

Generally, you want to avoid putting things in the alpha channel unless you’re trying to squeeze out extra information in a single texture sample, since the way textures are compressed means alpha takes as much vram as a full second texture anyway. It’s just more difficult on your end at that point to work with your own assets.

Usually though, it’s not worth the effort when just working out what you want a material to look like. It’s faster to work with textures when they’re still their own separate things. You can just load up the roughness map by itself as a third texture and plug it in directly to the roughness channel on the material

And yeah, you can just ignore the 3d preview in the material editor 90% of the time. It’s only good for seeing if everything’s connected up right, it doesn’t represent what things look like at all.

Cool, thanks for the tips!