Mesh.polygon_normals.value reports incorrect normal #109745
Operating system: Windows-10-10.0.19045-SP0 64 Bits
Graphics card: NVIDIA GeForce RTX 2080/PCIe/SSE2 NVIDIA Corporation 4.5.0 NVIDIA 531.79
Broken: version: 3.6.1 Release Candidate, branch: blender-v3.6-release, commit date: 2023-07-04 11:55, hash:
Broken: version: 3.6.0, branch: blender-v3.6-release, commit date: 2023-06-27 08:08, hash:
Worked: 3.1.2, 3.3.8, 3.5.1
Short description of error
C.object.data.polygon_normals.value reports an incorrect normal.
Exact steps for others to reproduce the error
- Open the attached blendfile
- Press enter in the Python terminal to evaluate
- It shows
Vector((-0.5773503184318542, -0.5773503184318542, -0.5773503184318542)), i.e. a vector that is diagonal towards negative x/y/z.
- Go to edit mode, in which the face with index 0 is selected.
- See that its normal should actually be
(-1, 0, 0), which is consistent with how the face normal is drawn.
The object in question has unity transform (zero loc, zero rot, unit scale), so the mesh data aligns with the world axes. It's just a cube, so all normals should either point in X, Y, or Z direction. Investigating the rest of the
polygon_normals array shows that there are many diagonals in there as well.
The blendfile has been created with Blender 3.1, the version that introduced the
No due date set.
No dependencies set.
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