[x3d-public] shows in Cobweb, BS Contact, FreeWRL. Does not show in X3DOM, Octaga, Instant Reality

[Vincent Marchetti]

The file 'gears.x3d':

1. Has one IndexedFaceSet. The coordIndex has 14544 integer items, and every 4th item is -1 -- indicating the face set is 3636 triangles (for a converted STL, it should be all triangles; so far so good)
2. The normalPerVertex field is false
3. The normalIndex field has 7272 entries, and every second entry is -1. However, according to the 3.3 specification, section 13.3.6; for the normalPervertex = false case there should be one
index for each face. The -1 end-of-face entries in the normalIndex field should not be there.

I have found that if I just delete the -1 values in the normalIndex field, the resulting x3d model renders ok in InstantReality 2.8 and in Xj3D.

While the original gears.x3d file passes the X3D Validators, if you open gears.x3d in X3D-Edit and try to edit the IndexedFaceSet node, you get error messages indicating that the -1 end-of-face entries
in the normalIndex field are incorrect.

Vince Marchetti
> On Apr 30, 2017, at 4:59 PM, yottzumm at gmail.com wrote:
> 
> Derived from an online free STL file, attached.
>  
>  
>  
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