Nice, to it seems to be quite a popular request here, which I'd think is quite expectable
About your suggestion, what do you mean? Something like:
1. Downsample volume.
2. Create mesh (apply scale matrix to vertex buffer)
3. IF region intersects different LOD of higher resolution:
* - Create the geometry for the intersecting border using the higher resolution LoD and add the border geometry to the vertex buffer (unscaled of course)
Is that your idea?
Edit: I think I will experiment with this idea for now (correct me for any mistakes or anything you might want to add) though considering it's a returning request here I am confident that TransVoxel will find its way into PolyVox in the near future and then I will be ready to use it in MLE
P.S. I managed to optimize the engine somewhat, rendering a map of the size of 1280 x 64 x 1280 with graphics settings on highest, no LoD or downsampling still, but will be needed for sure as complexity increases.
I also found that the decimator can worked instantly if I half the size of a chunk to 32x64x32 instead of 64x64x64, problem is draw calls increase by about 4 for achieving the same size of terrain. Problem.
Which gives me another reason to look into downsampling/lod/different extraction methods for lower resolution, reduced draw calls.
I am aiming for a terrain with the size of 4k x 128 x 4k at a point. With a size of 32x64x32 that is way too many draw calls (unless more efficient culling/batching can be added to the terrain) and way too much geometry. Yet this is a goal for the engine to be capable of, our game we hope to have in a size of 4km (although we might need to expand it anywhere to 6k or a maximum of 8k but 4km is our goal for now).