16 hours ago, Synvastian said:
its adaptive top layering, whatever is below the block you place, it attempts to replicate it (same with blocks to the side of it, sometimes it copies topsoil near the edge of roads, or gravel)
It's not quite that, I think. The game simply paints any terrain block the player places with the top-layer terrain texture which was there on the original map, no matter what is next to it.
In this picture, all of the terrain blocks are "forest ground", but regardless of height or surrounding blocks, they take on the texture of whatever was there originally - not copying the cement blocks.
As an extreme example, here is a "forest ground" terrain block placed on bedrock, beneath the road:
Yep, it's textured as asphalt.