Auto-Lightmap Density Optimizer | UE5 Python Tool

The Goal:
To eliminate the guesswork for Environment Artists, optimize memory, and speed up light-baking times. This Python tool automatically assigns the mathematically perfect Lightmap Resolution to thousands of assets in seconds, adjusting dynamically for their scale in the level.

Performance Metrics:
Successfully battle-tested in a heavy production environment: Processed over 17,000 level actors and 350 unique assets in under 40 seconds.

How it works (Technical Breakdown):

Geometry Scripting: The script reads the LOD0 geometry, extracts the triangles, and calculates the exact mathematical area to assign the most accurate texel density.

Smart Caching: To avoid redundant calculations on Instanced meshes, the tool uses a dictionary to cache the ideal resolution of an asset the first time it is processed.

Memory & Garbage Collection: Designed to be scalable for massive AAA scenes. A custom batch process flushes the RAM every 50 assets to prevent out-of-memory engine crashes during heavy load_asset() operations.

UX / UI: Fully integrated into Unreal via an Editor Utility Widget, featuring safety caps to prevent artists from inputting values that could break the VRAM budget.

Pipeline Dependencies:
As with any automated tool, "Garbage In, Garbage Out" applies. This script calculates the ideal texel density, but it does not fix poor UV unwrapping. The goal of this tool is to handle the math automatically, freeing up the artists to focus entirely on creating flawless Lightmap UVs!