Layer Blend Options

hi. i have some questions. i wanna use layer blend for my landscape. i have original textures and normal textures too, but there is some problems. i use materials from kite demo, i wanna use grass, 2 different kinds of rock, forest path, leaf path and stone path. and here are my questions:

  1. which one of them must be “LB Weight Blend” , which one “LB Alpha Blend”, and “LB Height Blend” and why?
  2. what is the work of preview weight? it just gets 0-1 numbers, which one must be 0 or 1 and why?
  3. i already used texture with their normal, but after painting, my materials are like diffuse, not diffuse with normal.
  4. i used “LandscaperCoords” for changing the size of them, but it won’t work. is there any way to do that and be realistic?



i just add textures as weight or height or alpha in random.
in the last picture there are 3 different materials, grass, leaf path, forest path. i think they are not very realistic.
if there is any documentation for my answers, please post it for me. thanks a lot.

You need to use a texture variation macro. Look in the grass material in the Starter content. You will see one there. For my landscape i have 2 diffrant grass textures to make it not like like you are tiling it.
For the landscape blend maps. you sould get splat maps for that saves a lot of work realy i does. if you use world machine it has a macro for that if you google it a bit more you will fine some great tutorials. the preview weight is used for showing witch texture you want to see, in the preview window ontop of the details. increase the mapping scale. And a other tip you can use upto 128 textures of you set in the texture sample node(I forgot witch one exactly) the second setting to sheard:warp.

thanks for your reply. your english is a little hard to understand, but i get the point. i’ll do whatever you said, hope i find my answer.

There’s a great tutorial/write-up here: WorldMachine + UE4: Full Workflow

In short:
**1) Weight Blend **ensures you have some value (0-1) for each material. As you paint more value of one material, it reduces the underlying materials. This is usually the most common blend mode.
**2) Height Blend **utilizes a height mask (sometimes stored in the Alpha channel of your baseColor map) to blend materials. This ensures that details defined by the white portions of your height mask show through other layers. For example, think something like rocks or dirt mounds popping through say a grass or sand layer.
**3) Alpha Blend **TBH, isn’t used all that often on multiple layers. Typically though, it’s used for your base layer. In your layer setup, set your base layer to “LB Alpha Blend” and it’s preview weight set to 1.0. This ensures that any black spots are removed when other layers are set to Height Blend.

From the UE4 Documentation, The image on the left is what happens when you use only Height Blend. Notice the black spots. Setting your base layer to Alpha Blend and preview weight of 1.0 makes sure those spots aren’t visible.

Instead of creating Layer Blend nodes for each channel (baseColor, Roughness, Normals, etc) use a “MakeMaterialAttributes” node for each of your layers, connect their outputs to a singe Layer Blend node, and finally connect it’s output to your main material. Note: in the material output node, you’ll need to change it to “Use Material Attributes”.

And finally, to tile your materials on the landscape, just setup something similar to this and you’ll get all the control you need. Note: in my example, I’m using the exact same textures for the near and far baseColor as well as the near and far Normals. There’s no need for two separate textures; it’s a waste of resources. Note: The “Alpha” node of the Lerps is connect to the output of the distance blend Clamp node as shown in image 2.

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I’m using the setup in that tutorial as well. Thanks to your input here I see some things that I could do better.