Optimising AI Generated 3D Models

Description

AI generated models/game meshes are woefully inappropriate for use in games or real-time environments without some heavy optimisation, they are typically far too dense and mesh heavy regardless as to what they represent or how seemingly complex the model is. With that said, it is possible to employ some simple techniques, primarily using the Decimate modifier, to correct the wastefulness of AI generated objects.

Duration: total c. 5 mins hr (00:05:00).
Info: 1080p.
Suitability: Beginner+.
Source: n/a.
Product ID: n/a.

Design note: additional considerations for optimising AI generated meshes;

Remesh/Retopo

Ideally, when working with AI generated meshes, they should be re-meshed or retopologised if they’re to be used as game-assets because they’re often significantly unoptimised for real-time rendering. If normal maps or other ‘surface detailing’ is required, a version of the object can be sculpted. Obviously this defeats the purpose of using AI generated 3D objects, however, the broader point still stands that wherever possible, versions more appropriate for use in games should be made using the AI generated 3D object as a source reference.

The difference between AI generated meshes (upper row) and remeshes objects (lower row), especially those used for games or assets that need, or use, physically based materials, i.e. normal maps, roughness, specular etc.

UV Map

Because of the way AI generates 3D objects UV maps are going to be equally as dense as the mesh, and typically unwrapped using ‘box’, ‘lightmap unpack’, or some form or combination of UV mapping styles relative to how the mesh was made, not how it should be optimally unwrapped. As a consequence of this, once the Decimate Modifier is used, UVs will be degraded to the same extent as the degree of mesh reduction. In this context ‘re-mapping’ the UVs won’t fix the problem because their placement or mapping is relative to the initial state of the object and how textures were generated for it. In other words, moving, editing or adjusting UVs will result in a mismatch between UV, mesh and texture mapping, so they can’t typically be remapped.

After using Decimate, UVs will be equally reduced but unlike mesh structure, don’t have the flexibility to adjust to the reduction causing them to break or display gaps

Timestamps

Times are approximate;
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