Improve UX for MGE XE grass mods

[AnyOldName3]

MGE XE, the graphics mod for Morrowind which hooks into the engine and makes it do various pretty things, adds a system for grass and other groundcover, which is used by several mods. These mods come as .esp files plus meshes and textures. However, they absolutely shouldn't be loaded as plugin files by the game. They're only intended to be loaded by MGE XE's distant land generation tool, which then outputs some files which MGE XE uses at runtime. If you make the mistake of activating them as regular plugin files and then launching the game, you'll have terrible performance, and two copies of every blade of grass, one of which won't sway in the wind, and will likely have other issues, e.g. unwanted collision and rendering issues (as the distant land generator ignores/overrides certain Nif properties in grass files).

This basically means a modded Morrowind setup will likely have a bunch of ESP files which need to be in the VFS when the distant land generator is run, but shouldn't be in the enabled plugin list when the game runs.

There's basically nothing that clearly indicates whether an ESP is a grass file or a regular ESP, so we can't do anything completely automatically, but maybe we can do something which allows the user to mark an ESP as grass, and then change what enabling it means so that ends up in the [DLWizard Plugins] section of MGE.ini instead of the [Game Files] section of Morrowind.ini.

This would also be useful information to make available to plugins. The OpenMW export plugin could add grass files to OpenMW's groundcover list if it had some way of finding out that was the right thing to do.

[Holt59]

Maybe this can be done as a plugin? It should be possible to

• Add a UI to let user select which ESP are grass mods.
• Add callbacks to update the .ini file when necessary (or maybe just when closing the UI).

[AnyOldName3]

That could work, but wouldn't be great UX-wise, which is kind of the point. I'm thinking of something more like being able to right-click the ESP in the plugins tab (which I guess could be handled by a context menu plugin if we ever get those implemented) and then do something to visually indicate that it was now considered grass. That could just involve highlighting it green or adding a new icon to the flags column, which are also things not wildly inappropriate for plugins to be able to do, but they're not things they can do yet.

There's also a decent case for the plugin it gets added to (if it's not a core feature in the main executable, which would be messy anyway) to be the main Morrowind plugin itself. MGE XE is pretty core these days. It's a hard requirement of MWSE, and is already one of the executables we pre-populate the list with.