Optimization - Room Bounds and Portals - No PreVis and PreCombines for Interior Cells

–Bethesda Tutorial Optimization

Preface

Optimized Room Bounds & Portals or just ORBP alters/removes PreVis and Combined references from interior cells and thus force the game to use Room Bounds and Portals. Room Bounds and Portals are much more optimized tools to increase performance on user end. Since, it allows to cut off a lot of rendering, due to not rendering sections of the interior that are beyond the current Defined Room, only rendering the space beyond fully, when player goes through the Room Portal. This technique was probably dropped during development of FO4 at some point since its time consuming to setup.

Some Fallout 4 interios have Room Bounds and Portals available but almost all interiors cells use PreVis and Combination, which probably override Portals and Room Bounds. Since its far less time consuming to generate Combined and PreVis meshes, Room Bounds and Portals can be seen as a leftover in the game files, references.

During development on this mod, i noticed many (leftover) Room Bounds were inproper setup and did not cover the entire area or had misplaced Portal(s). This was fixed. Furthermore, i figured that Room Bounds net into an even more compact cluster increase FPS so much, i could not believe. This was done on an iGPU to instantly notice slight changes on FPS. My observation proofed to outclass the PreVis and Combination logic for interiors totally. Since then, the idea of this mod was born.

The foundation was led to purge the Cell Header and make room for Room Bounds and Portals ... By removing the PreVis and PreCombine references the game directly unflags the former Combined statics to be true Placed Objects. Just like any other object class. This would make the mod best suitable for modders since it allows to alter the entire cell, all objects!

Overview

In short this mod ...

- Affects Interior Cells

- Alters PreVis

⠀- Adds the "No PreVis" flag to ALL interior cells

⠀- Blanks PreVis Files Timestamp (VISI)

⠀- Blanks PreVis Reference Index (XPRI)

- Alters PreCombination

⠀- Blanks PreCombined Files Timestamp (PCMB)

⠀- Blanks Combined Reference Index (XCRI)

- Unflags static objects: "" to "Placed Object"

- Increases performance due to Room Bounds and Portal

⠀- Optimizes Room Bounds and Portals (WIP)

⠀- Adds missing Room Bounds and Portals (WIP