Dissapearing Land, a fix

[Alasdair]

A while back I posted a semi-guide on the skyrim outer-core boards, due to problems whereby when an esm (specifically the SkyrimResourceMaster.esm plugin) is loaded other than oblivion.esm some of the land in tamriel vanishes (especially in cities). however it has become clear that other beyond cyrodiil landmass mods have been having this problem and I was asked to post what I wrote here.

If you can't be bothered to read it, the rough gist of it is: keep your esm's clean of refrences to oblivion.esm, and any reference to the tamriel worldspace in the master will cause dissapearing land problems. simple!

Originally posted by Alasdair
Basically as you know, when you load the current Skyrim resource master you get something like what is shown below:



Now the problem lies in oblivions use of formID's, basically every object is assigned a formID in the format YYXXXXXX, where YY is the plugin number and XXXXXX is the object number. each esp plugin is given a hexadecimal number from 01 to FF in the YY part of the formID, the XXXXXX object number is pretty self explanatory.

the number 00 is reserved for the oblivion.esm master file, it is always 00 and this allows mods to access it, all the other YY parts of the formIDs are not static and will change depending on the number of mods installed (this is why it immposible for mods to contact one another). When you make a new .esm it also uses 00 for it's YY part of the formID. Problems seemingly occur when one .esm attempts to modify something in the original .esm. take a look at the screen shot below:



Oh dear, looks like our Skyrim resource master is changing Tamriel itself...

The game seems to be smart enough to look for the exterior in oblivion.esm, but when it comes to child world spaces (i.e. cities) it's quite a different story. the game seems to look for Tamriel's land data in Skyrim's resource master first, before it looks in oblivion.esm. unfortunately in our case the game engine finds the (rather flat and non-existent) Tamriel landmass data in SkyrimResourceMaster.esm and proceeds to use it in the cities.

So to fix this rather awkward predicament we just get rid of the Tamriel reference as shown:



And since this is a Resource master we don't need no cells either, so lets get rid of them...



there is also plenty of other garbage in the file that needs removed, but that won't cause too many problems (not serious ones anyway )

And now to see the results of our handiwork!



Voila! now NPC's can be safe in the knowledge that they won't fall 200 feet into water when exiting their own homes!

[Razorwing]

Thanks for the information, Alasdair!

What do you think about the theory that if the player plays with a mod (in esm format) that affects Oblivion.esm *but* does not alter anything with the landmass, that that can cause problems in another mod he's playing with (also in esm format) that does affect landmass but is in itself clean? Because I've thought that explains the bug some people experience while playing Reich Parkeep. I've never experienced the bug myself, ever - which puzzles me - but it seems every other player encounters it.

[sandor]

Thanks Alasdair for sharing your findings.
I think you explained it very well!

[Alasdair]

In order to avoid errors, an esm should ideally be completely clean of any references to anything in oblivion.esm.

I would think however that having two .esms loaded (not including oblivion.esm) at once is practically an invitation to errors, doesn't matter what they contain. For example one esm may use the formID 00000CE9 to reference a plant pot, while another might use that same formID for a NPC. the game most likely can't tell the difference between the two.

[sandor]

Originally posted by Alasdair
In order to avoid errors, an esm should ideally be completely clean of any references to anything in oblivion.esm.

I fully agree.

Originally posted by Alasdair
I would think however that having two .esms loaded (not including oblivion.esm) at once is practically an invitation to errors, doesn't matter what they contain. For example one esm may use the formID 00000CE9 to reference a plant pot, while another might use that same formID for a NPC. the game most likely can't tell the difference between the two.

This is not true, FormID's starting with 00 are related to the Oblivion esm.
If you see this, it means your (second and/or third esm) esm altered the Oblivion.esm. New content withnin the second and third esm will have a mod index of 01 and 02.

[Isildur_Diren]

I have a problem with disappearing land as well. Only its in the Silgrad, Steadholm areas. When I go to Cheydinhal and go threw the portal I end up on a sea bed with big holes in the landmasses. It doesn't seem to effect cyrodiil and the funny thing is that in the construction kit silgrad is perfectly fine. (having no landmass probs) Its only when I play the mod that problems occur. Does anyone know what's wrong?

[The Old Ye Bard]

Originally posted by Isildur_Diren
I have a problem with disappearing land as well. Only its in the Silgrad, Steadholm areas. When I go to Cheydinhal and go threw the portal I end up on a sea bed with big holes in the landmasses. It doesn't seem to effect cyrodiil and the funny thing is that in the construction kit silgrad is perfectly fine. (having no landmass probs) Its only when I play the mod that problems occur. Does anyone know what's wrong?

It's your load order.

(P.S. Check your PM box)

[Isildur_Diren]

Yeah that would make since. I'm having trouble changing the order in which they load, do I need the mod manager?

[sandor]

The Silgrad_Tower.esm has to be loaded second after the Oblivion.esm.

To change the load order use OBBM.
You can find it here.

[Isildur_Diren]

Ah sweet. Thanks I really appreciate it.