Wrong vertex normal in a custom UV stage (on landscape only)?

[c4tnt]

I tried to make better texture mapping on steep walls of landscape and got a surprise - when my test material is applied to a landscape it looks like VertexNormal node always return (1, 0, 0) vector while node is used to compute a custom UV mapping. More surprising that the same node works fine in the same material while computing something else - color for example.

I made a test material:

and applied this on a cube and on a landscape:

On a cube it works as excepted, but on a landscape normal never changes.

[anonymous_user_3221808d]

Would pixel normal maybe return a different result or must this be in the vertex shader?

[c4tnt]

In pixel shader it works fine, but on mobile devices it dramatically decreases texture quality Without custom UV Unreal Engine generates a dependant texture sampler that returns heavily blurred color. Actually it surprising that material works fine on anything except landscape.

[anonymous_user_83fd587c]

Makes sense. I did my own tests and this is the same for me as well. One funny thing is if you rotate the entire landscape then the normals do update. It’s just that they are always all facing the same direction.

[anonymous_user_03287fa5]

Hello, do you find any solution to this finally ?

[c4tnt]

No, problem is still existing on UE 4.15.2
There is only one solution - not to use a precomputed UV’s on landscapes