There’s a ton of work that goes into 3D modelling, so when an AI generates one it should be easy to spot. For example, baked-in lighting, mushy meshes, and high polygon counts are all giveaways that generative AI has been used.

With 2D art, it’s easy to recognize if an image has been AI generated, simply “look at the fingers.” However, with 3D modelling, it’s a bit different.

Over at the social platform Bluesky, Liz Edwards made a thread explaining how to spot an AI generated 3D model.

Bad Textures and jumbled UVs

She was scrolling on Fab (which is a site/shop where you can purchase 3D assets), and she pointed out glaring issues such as “baked-in lighting”, and that the image is projected automatically from a 2D image, leaving artifacts.

She then accessed the model and looked at its wireframe, noting that the UVs will usually look like a “dense automesh” that “looks like a jumbled mess.”

She’s also pointed out that AI generated crate models (such as the ones sold in Fab) have around 50,000 triangular polygons, whereas the amount that you’ll need for a game would be about 500 triangular polygons (at the upper end).

3D Models generate with AI can create confusion

Edwards has warned that the traits above don’t automatically identify a model as being generated by AI assistance/tools. For example, 3D models captured with photogrammetry share these same traits. The difference being that those models have natural textures and are usually free of artifacts, they also have coherent and naturalistic details.

If you aren’t animating a given 3D model, or you’re unbothered by the high count of polygons you may shrug off models that were created with photogrammetry. However, Edwards warns that even these models can have coherent inconsistencies that can look unsettling or weird when viewed close up.

She also points out that the meshes created from AI are “rarely” symmetrical and are often melded together as “featureless blobs”, these “blobs” often feature the feet or arms of animals/humanoid models, which will make it impossible to pose or even animate them.

(Link to article: https://www.gamedeveloper.com/art/how-devs-can-spot-ai-generated-3d-models)