Why is smoothterrain so choppy? i swear it was not this choppy before

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The terrain hills look real weird now and im not sure why? they have these weird lines all over them that i pointed out and you can clearly see to the left and im not sure how to fix this?

It might be LOD, the further you go from the terrain the less detailed it gets for better performance. No idea how it randomly happened though.

It never was like this before. and even up close its lke this? i mean its SMOOTH terrain for gods sake. what did they do???