3D troubleshooting answers
Diagnose texture references, UV stretching, normal-map shading, face orientation, scale, density, rig deformation, collision, and print geometry. Start with the visible symptom, isolate the responsible stage, then retest the delivered asset. Each answer includes official sources, limits, and acceptance checks. Pro covers generation and static export; a plan upgrade is not a repair for broken mapping or import settings.
Why do faces disappear when you rotate a 3D model?
First orbit the model with an opaque material and identify whether the same surface is visible from the opposite side.
Read Inverted normals guideWhy does a texture stretch across a 3D model?
A UV map assigns positions on a two-dimensional image to faces of a three-dimensional mesh.
Read UV stretching guideWhy does a normal map make a 3D model look wrong?
Normal maps change the surface directions used for lighting; they do not rebuild the silhouette.
Read Normal-map shading guideWhy can a player walk through an imported 3D model?
First confirm that the intended object has a physics body and an enabled collision shape, not only a visible MeshInstance3D.
Read Collision mesh guideWhat is a PBR texture map?
Treat a material as a set of inputs rather than one painted image.
Read PBR maps guideWhy are textures missing after a 3D import?
First distinguish missing geometry from missing surface data.
Read Missing textures guideHow to check a non-manifold mesh before printing
Start with a copy of the source mesh.
Read Non-manifold mesh guideWhy does a 3D model import at the wrong scale?
Start with one known dimension and the receiving tool's unit settings.
Read Incorrect scale guideHow to reduce an oversized 3D asset
First identify whether the problem is a slow download, high geometry cost, texture memory, or scene complexity.
Read Oversized assets guideWhy does an imported character rig deform incorrectly?
Separate a geometry issue from a rig or import issue.
Read Rigging problems guide