Why Landscape materials sucks

After attempts to create multi-layered landscape material, I realized that landscape performance is really bad. I had material with 5 layers on one 500x500 meters landscape and the performance penalty was HUGE. I was sampling just a few textures. I am wondering why other engines I have seen (Crytech, etc.) don’t have such a big problem with multiple “layers”. Is someone working on it? I hope in UE5 nanite will be able to deal with it.

What is your opinion? Do you have any ideas about why it is so slow?

OK… It turned out that I am just a big idiot. Performance is OK when I play the standalone game, not just viewport There is still a performance hit, but not as big which is fine :smiley: