Kasoroth wrote: ↑03 Oct 2018, 09:26Perhaps if the openmw-cs had a quick tool for taking a snapshot of a selected area of the terrain mesh and auto-generating a static mesh from it, you could build a mountain with the terrain editor in the construction set (or select an existing mountain in the game world), snapshot it to make the "mountain surface" static mesh (with holes in it anywhere that wasn't selected when you created the snapshot). Then you could lower the real terrain mesh down below it to create the hollowed out space as you suggested, but leaving the static mesh copy of the original mountain in place above it.
I'm not sure if adding this "terrain snapshot" capability to the CS would be easier or harder than adding "hole boring" capability to the terrain layer, but it would confine the changes to the CS (since the game engine itself would just see a static mesh and regular non-holey terrain below it), so it seems less likely to require a change in the actual file formats.
There IS a 3rd party utility called cell to nif which was created by Yacoby, and this does exactly what you are suggesting (create a snapshot of a cell which is converted to a NIF file to make changes in a NIF editor, such as Blender w/ NIF extension). A quick search revealed the sourcecode as well:
Perhaps we can petition Yacoby to allow us to add the source to openCS? In theory its available for grabs but Yacoby has done many such projects and we would do well to keep him on our side.