You can export 3D layers in Photoshop as files in several supported formats. This blog post touches upon considerations for exporting 3D layers as U3D files.
To begin with, ensure that any 3D layers that you’re exporting as U3D have only triangular object geometry. Additionally, keep the following export-related limitations in mind:
- Export of higher-level primitives, such as NURBS, splines, and curves, is not supported.
- Texture mapping is limited to only one diffuse map per material. Export of ambient, specular, luminous, or opacity texture maps is not supported.
- Export of material animation is not supported.
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