Hey guys! This has been suggested quite a few times so I'll write about what I'm currently working on here.
Right now I'm finishing up the new terrain tessellation code. It used to create a nearly ideal tessellation that resulted in very few polygons but lots of draw calls and lots of data sent from system memory to graphics memory. This is what the old tessellation looked like:
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Now, I think this is a beautiful tessellation. It focuses detail closer to the camera and on bumpy areas and also has no T-junctions. It's a lot of the reason why MXS could do big maps with no draw distance limits on ancient graphics cards. But it's slow today.
The new way does the same basic thing, except instead of tessellating down to 8 triangle fans, it works on 16x16 grids of those fans. So it's much less accurate and makes way more polygons, but everything now resides in graphics memory and is more uniform so the GPU can spend less time waiting for memory and also work in larger batches. Here's what the new way looks like:
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Kind of sad to lose the more detailed tessellation but this is unquestionably better on modern hardware. Testing on a GT 1030 it went from 68 FPS to 127 FPS on the 4k thousandacres terrain.