Specular artifact when I use MatLayerBlend_Standard?

[mandaxyz]

Hi! Please help, I believe that this problem is well known because it's very easy to occur the problem with MatLayerBlend_Standard.
I don't know how to solve this problem on Specular Artifact, I tried to increase the hardness of the texture mask but I still see the artifact because it's thin and bright.


Here is the material, and the grass layer is the standard grass in the Starter Content but it's inside the function MF_Grass01.

[mandaxyz]

BAD SOLUTION:
I found a bad solution by myself but this problem is almost impossible to solve, because the grass roughness is 1.0, and the path roughness is 0.5 and the specular becomes visible between the grass and the path, because the roughness at that point is 0.75, it's too complicate to explain.

Weird solution: I force match the roughness of the path to the roughness of the grass (1.0).
Problem: I cannot use a different roughness for the path.

Does anyone has an idea?

Edit:
In a partucular case like these, without tessellation. Don't use a gradient of alpha for the mask, but either use alpha = 0.0, or alpha = 1.0.

if (oldAlpha > 0.5)
    newAlpha = 1.0;
else
    newAlpha = 0.0;

[NilsonLima]

How was set Specular inside MF_Grass01 ? That value is being blended aswel. I usually don't touch values for Specular unless there is glass and water materials involved, anything else just does not work right in PBR (while working with metallic and roughness).

[rosegoldslugs]

Also you have a metallic parameter for what seems to be only non-metal surfaces. Did you adjust that value as well? It can cause similar artifacts since it's controlling specular too, especially when going from a metal to a non-metal surface.

[mandaxyz]

Thank you all for the help. NilsonLima asked what is the Specular of the grass inside MF_Grass01, and the answer is it's using the default Specular, because no connected node, I think it's 0.5.

Anyway, I give up my method because the path doesn't look realistic, and I don't know how to make it looks better, maybe I must give up this method.
I think I'm going to go more wild to solve the problem, I mean use a tessellated path and spread some plants on the path. That's the only solution I think. Does anyone have an idea?

Park From Lucid Dream
Let me talk about my art, I'm going to make a little animation. I use Unreal Engine for Hobby, that's why I can make a better work. It took 20 days to prepare the trees and plants because the materials weren't directly ready, the Object Space Normal Maps for the rocks were so complicate for example. And it took only one day to make this scene by using the assets with foliage painting, you saw me posted this thread yesterday without anything on the scene. It's a hobby, that's why I could be patient for 20 + 1 days.

[NilsonLima]

I would propose to change the path material completely for another one, maybe cobblestone, bricks, even make the path wet using Clear Coat would help to get rid of the specular issue, since specular would be used for the wetness anyway and would introduce some darker area at the scene which would help contrast with the vegetation and since eyes like to shift attention to colorful areas would automatically move from the darker path to the grass and trees.

[mandaxyz]

Thanks, I use a tessellated cobblestone and it looks better, there are some grass above it and it's not bad.
Note that the grass on the path is not good yet, I will improve it by putting some plants, and smaller grass.

I have a problem, the resolution of tessellation cannot be changed into higher resolution, I spent some time but not solved yet. If I will never able to solve it then I have to start a new thread.

BAD SOLUTION: Delete the whole landscape, then create a new whole landscape with smaller scale, for example 25% compared to the previous. But with this solution, I have to repaint all the foliage from beginning.

[NilsonLima]

You can place a spline for the path and it will not use the same resolution as the landscape I guess. Another possible solution is to lower the landscape where the path goes, and place a mesh for the path where you can control the resolution and get a smooth tessellation there.

[mandaxyz]

Placing a higher quality tessellated separated spline to replace the path is a good solution. It's good for performance too.

Thank you so much. I don't know how to thank you because I tried to delete the whole landscape and tried to create a landscape with smaller scale with higher quality. But thanks to you I don't have to do it.

This is my other thread, it's not important anymore but I tried to delete the whole landscape: https://forums.unrealengine.com/deve...lation-quality

[NilsonLima]

You can intersect the splines, but you will need to improve the materials to have vertex and displacement blending. I remember a good tutorial, but couldn't find them, there are these you could check out thou:

[mandaxyz]

Thank you so much, the intersection is probably a challenge.