Landscape material error

[taking9]

Landscape material error.
Partly the material disappears.

[MOTHERJAVA]

I've also encountered this exact problem. The only thing I can seem to find that helps this is to make sure that you paint your landscape layers in relation to the order they appear in the material editor, though I'm not 100% sure if this its what causes the problem.

I hope this helps, and I'd love to know if there is a better solution to this issue.