UE4 - Vertex painting and material layering

Necrodark

So i've been setting up my material layers in UE4 for my scene and I want to use vertex painting to paint on moss instead of masking it so i can have more control and make adjustments on the fly. The problem is i cant get vertex painting to work, right now i have it in a blend layer because doing it from the material layers didnt work like i wanted it to. Whats the right way of doing this?

I've got 2 material layers, stone and moss, and i want to blend the moss ontop of the stone.
here are some screenshots

Benjammin

I'm a little confused by your post. Is it working now, with blend layers, and how was it not working before, exactly? Generally speaking, you'll want to use the vertex color channels separately, as they're just being used as a mask. Also, make sure you can actually paint colors before you start troubleshooting shader networks.

Necrodark

@Benjammin
Its not working right now, I did get it sort of working with some other method (i forgot exactly what it was) but the base material turned like red and purple. About being able to paint, when i switch to RGB channels the surface with the Master material on it is invisible.

Also when i did it through the stone material layer it painted weirdly, like by chunks (geometric, as if its painting in tris or something)

I can give you more info tomorrow when i have time to fiddle around with it some more, sorry for the lack of context.

mashonoid

In your height lerp Material Function, plug the Vertex Paint's RGBA (only one of these channel) to Transition Phase. Transition Phase decides which Vertex Paint's RGBA channel will TRANSIT to the next texture. So in your A(V3) and B(V3) will contain your 2 textures. A will have the base texture and B will contain the 2nd texture which will be controlled by your vertex paint.
 Hope this helps