On PR #50 faces merging was removed, since it's impossible to work with each voxel using merged faces. The solution would be to generate two meshes: One merged and another "raw", this way we can swap between meshes when entering or leaving underground areas and only affected chunk will have full non-merged faces.
Note that this will heavily impact performance, since faces merging and voxel vertex generation will be done twice, also the cache data size will also increase, which may increase #49 priority.
On PR #50 faces merging was removed, since it's impossible to work with each voxel using merged faces. The solution would be to generate two meshes: One merged and another "raw", this way we can swap between meshes when entering or leaving underground areas and only affected chunk will have full non-merged faces.
Note that this will heavily impact performance, since faces merging and voxel vertex generation will be done twice, also the cache data size will also increase, which may increase #49 priority.