New cell vs Duplicate cell

[Nomumbra]

I'm making a mod that makes changes to the interior of an existing cell.

 

What are the advantages of making it a brand new cell?

 

The disadvantages of making a duplicate of the existing cell?

[dubiousintent]

If you make changes to an existing cell, you are going to 1) have a conflict with any other mod that makes changes to that same cell, and 2) likely break anything vanilla that depends upon something you changed, which may not be obvious. Making direct changes to the vanilla game/DLC ESM files is a BIG "no-no, bad, slap-your-hand-with-a-ruler" mistake. Create your own ESP that then can "override" the vanilla cell records when installed. You run the same risks, but at least backing out your mod will restore things to normal.

 

Please see 'Copying interior or exterior cells between plugins' section of the wiki "Getting started creating mods using GECK" article.

 

-Dubious-

[madmongo]

I have done both. 99 percent of the time I will modify an existing cell. The only time I will completely replace a cell with a new one is when there is absolutely nothing that I want to keep in the original cell.

 

For example, I created a mod that completely replaces the interior of the H&H Tool Factory. To me, the entire interior of the tool factory was complete nonsense. The office parts look like offices, but the layout didn't match the exterior of the building. The so-called factory part was just a small flooded area with some random industrial parts from the GECK tossed in along with some catwalks that made no sense whatsoever. It looked nothing like a factory and there wasn't anything that looked even remotely like it could be used to make tools. They even screwed up one of the terminals. Anthony House's terminal has a note in it signed by Alexander House, so whoever created that cell couldn't even keep the name straight.

 

The factory part needed completely redone, and the office parts needed completely redone as well since they didn't match the building exterior. So, in this case, since I was completely scrapping everything inside the cell, I created a brand new cell to replace the old nonsense interior. Actually, I ended up creating three cells (first floor, second floor, and a flooded basement as kind of an homage to the original flooded area of the factory). The only edit to the vanilla game was therefore modifying the door so that it would take you to the new interior instead of the old interior.

 

As Dubious said, you have to be careful when you do something like this. I made this mod for my own personal use, and I knew it didn't screw up anything that I cared about in the main game. I did end up releasing the mod on the Nexus, and while I didn't break anything in the main game, I did break the Bison Steve mod, since it placed something inside the original tool factory. I ended up creating a compatibility patch for those who wanted to use both my mod and the Bison Steve mod. If anyone ever chooses to restore and finish the cut quest in the tool factory, my mod will break theirs.

 

One important note here is that my mod is an esp, and the Bison Steve mod has both an esp and an esm version available. Creating patches to esp mods doesn't work very well when you have multiple esp files. There are ways of doing it but it's clunky since you have to work around the fact that an esp can't depend on another esp without some fiddling. I was lucky that the Bison Steve mod had an esm version that I could just include as a master to my mod to create the compatibility patch. If your mod is an esm (or at least mostly an esm) that will make compatibility patches much easier.

[Mktavish]

The down side for not keeping the old cell - ID is that cell conections via their teleport doors and the navmesh finalize. Will not work correctly ... but a simple re-finalize navmesh for connectors will fix it. At least I think that will work without having to turn an esm into esp to do that.