the way bone weights in an fbx file are interpreted seems to be wrong #46020

New Issue

David O'Sullivan · 2015-09-05T03:21:40+02:00

David O'Sullivan commented

2015-09-05 03:21:40 +02:00

System Information
Win7 x64

Blender Version
Broken: 2.75
Worked: (optional)

Short description of error
When I download an fbx from Mixamo that has been 'auto rigged', if I import it directly into Unity, the bone weighting looks good/correct. If I import the file into 3DS MAX and export it again and then import it into Unity, the bone weighting looks good/correct but if I import the downloaded file into Blender and export that as fbx 7.4 and import that file in to Unity the bone weighting looks bad/incorrect.

Obviously I cannot see what the bone weights are in the actual downloaded file because I do not know how to read binary, but what I can see is that when the Mixamo fbx file comes into Blender the bone weights appear to be a) un-normalised and b) rudimentary. This may be accurate to how how Mixamo's auto rigger generates them.

BUT Unity interprets them in the same way they seem to appear if I import the file into MAX and export it and then import that file into Blender- i.e. Max seems to auto normalise the weights in the same way that Unity does.

However executing 'normalise all' on the weights on the original downloaded file in Blender does not provide the same result. So I am just wondering if there is some data in the original downloaded fbx that the Blender fbx import is missing somehow?

Exact steps for others to reproduce the error
Based on a (as simple as possible) attached .blend file with minimum amount of steps

**System Information** Win7 x64 **Blender Version** Broken: 2.75 Worked: (optional) **Short description of error** When I download an fbx from Mixamo that has been 'auto rigged', if I import it directly into Unity, the bone weighting looks good/correct. If I import the file into 3DS MAX and export it again and then import it into Unity, the bone weighting looks good/correct but if I import the downloaded file into Blender and export that as fbx 7.4 and import *that* file in to Unity the bone weighting looks bad/incorrect. Obviously I cannot see what the bone weights are in the actual downloaded file because I do not know how to read binary, but what I can see is that when the Mixamo fbx file comes into Blender the bone weights appear to be a) un-normalised and b) rudimentary. This may be accurate to how how Mixamo's auto rigger generates them. BUT Unity interprets them in the same way they seem to appear if I import the file into MAX and export it and then import *that* file into Blender- i.e. Max seems to auto normalise the weights in the same way that Unity does. However executing 'normalise all' on the weights on the original downloaded file in Blender does not provide the same result. So I am just wondering if there is some data in the original downloaded fbx that the Blender fbx import is missing somehow? **Exact steps for others to reproduce the error** Based on a (as simple as possible) attached .blend file with minimum amount of steps

David O'Sullivan commented

2015-09-05 03:21:40 +02:00

Changed status to: 'Open'