Unofficial Oblivion Patch excessive draw calls fix

As of November 2021, this fix has been incorporated into the Unofficial Patches! This means there should be no reason any more to install this mod, as this problem only existed in earlier versions of the patches, but not in the vanilla game. However, the QTP3 patch has not been updated, yet.

What is this and why should I care?

Short version:

This mod fixes an issue present in some of the meshes from the Unofficial Patches for Oblivion, Shivering Isles, and the DLC, which can decrease performance in certain places due to excessive draw calls caused by NiTriStrips with more than 1 strip. Draw calls are commands from the CPU to the GPU to draw a 3D shape, and therefore increase CPU load. As Oblivion can only effectively use a single CPU core, additional draw calls almost certainly affect performance negatively. The meshes were fixed by optimizing them with Pyffi. As I don't know if the UOP will get updated at some point to fix these meshes, and not everybody can be expected to use Pyffi themselves, I decided to upload this patch for the Unofficial Patches.

Sniff can be used to detect problematic meshes (Find several strips), however, sometimes only the collision meshes are affected, which is fine, since they are not drawn and therefore don't cause draw calls. I might add patches for other mods in the future or provide a list of mods with problematic meshes, if I don't have permission to upload a fix. I have decided against uploading fixes for specific mods, at least for now. It would be impossible to make sure that the Pyffi optimized meshes all work correctly, especially for larger mods.

Update: The fastest, easiest and potentially safest way to fix the issue is with Sniff itself, as it can convert NiTriStrips into NiTriShapes. This also works with things Pyffi cannot optimize, like Hair. Still, always backup your files!

So far, I found:

[]Balanced Magic

[]Mesh Improvement Project (two meshes are affected)

[]Harvest Containers

[]Jungle for Everyone (Palm Trees Update10 only)

[]Weather: All Natural (BSA, Mostly collision geometry, which should be fine, but there is a single, very simple mesh that is used in a few places to cover up windows. Can probably be neglected, as just a few interior cells are affected)

[]Bomret's Texture Pack for Shivering Isles v1 with meshes from USIP (two meshes, but one of them is not used by the game, and the other appears to be identical to the one from the Unofficial Shivering Isles Patch, so you can just use that one, it is "SEWallPost01.nif)

[]Maskar's Oblivion Overhaul (BSA)

[]Coms Argonian Headstyles v2dot1 (Pyffi will skip these automatically because they are hairs, can be triangulated with NifSKope)

[]Slofs Oblivion Better Beasts OMOD

[]Argonian Beautification