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Using bump map on a little area

Hello, I’ve imported in Unreal Engine a 3D model that I made in Blender some time ago, but I’m facing a little problem with materials.

The following is the material set-up for Blender Cycles:


In the top right you can see the UVs: I unwrapped the faces that I needed to fit the texture, then I used the UV to apply the bump map only to those faces.
This is the texture that I’m using as a bump map. I found the logo on Google Images and I’ve adjusted it using photoshop:
JWL.jpg
(I’ve filled the background with black just to let you see the image, it should be transparent).
My problem is to do something like this in Unreal material editor. I read the documentation about bump maps and I’m quite confused on how to use them. I’ve tried everything possible but it doesn’t work. I also tried to convert the texture to a normal map using a free converter online, but nothing changed.
This is the material that I have to use (from the free automotive pack by Epic):

Can someone give me some advices? thank you in advance.

Unreal engine uses Y- Normal Maps rather than bump maps, there are two main ways to achieve this result, the first would be to unwrap the rim and place the alpha in the correct position on the unwrapped texture

The second choice you have is to map a plane the same with the alpha on and place it in the correct position

for both the above you will need to convert your bump map(alpha) to a normal map through a program like Xnormal photoshop plugin or ndo

They can then replace the vertexnormalWS node

Bare in mine as as unreal uses y- you might need to flip your green channel either in unreal or through your chosen converter as it stands the white area will stick out the black area will not

If I didn’t misanderstood it, I’ve taken the second choice. I created a mask in photoshop for my normal map and then I’ve imported both in Unreal.

The result is not that great, it doesn’t even seem to be engraved. I don’t get if my node set up is wrong or my normal map is of very bad quality.

Maybe try using BumpOffset

Insane bump-plug in for gimp will give you an outrageous normal, and height map. It’s easy to install. Also using bump offset along with the generated maps. Normal map though you would need to create a png of only your logo, or it would stamp the black as being inside the wheel, and extrude the white.

I’ve tried out the Photoshop filters “Generate Normal Map” and “Generate Bump Map” and these are the results:

JWL_bump.jpg
I’d say they look quite good, so from now it’s no longer about the textures’ bad quality.

I’ve tried to use bump offset node, but I the only texture that I have in this material is the new normal map (it must be plugged-in the UV input of a texture sample node)
So I tried this, but the result is that error:


Then I found something about using a mask on a normal map: I had to create a blank normal map using photoshop (just a 64x64 square colored with 128, 128, 255) and mix it with a lerp node. I don’t think that could be different from plugging my normal map directly into the normal pin of the material, but whatever, it’s just a try:

The normal map is ok, but the general look is so weird:


I really don’t know what’s happening :confused:

Honestly, I’d just make a small plane for where the embossed logo is, and assign its own unique dbuffer decal shader. That way you can have a separate material for the wheel body, with its own normals and such.

That seems to be the easiest solution, I guess… I’ll give it a try, thanks