Thanks, seghier, that sounds interesting, going "under the hood".
Here's a comparison again, between OBJ and STL output. That's not good at all, can't be just "photoshopped out". Trouble is that Studio is sold with OBJ import capability for software for which there is no plug-in. Like shown here, it is not usable.
Imported - no material assigned. Nothing strange to be seen
Shiny real scale material assigned - mesh not smooth, jaggy triangles, coordinate jumps.
Closeup of STL and OBJ - each shows (different) issues
Alias OBJ anatomy:
v 0.02699572 -4.605813e-014 0.02136904
v 0.0170726 4.784725e-013 0.02309592
v 0.007113768 -1.875122e-013 0.02449689
v ...
vn 0.1874676 3.185799e-006 0.9822708
vn 0.1553852 1.455842e-006 0.9878539
vn 0.1231873 5.030049e-007 0.9923834
vn ...
vt 0.06722516 0
vt 0.4232833 0
vt 0.7793415 0
s 1
f 20/20/20 8/8/8 9/9/9
f 6/6/6 8/8/8 20/20/20
f 19/19/19 20/20/20 10/10/10
f ...
s off
Rhino OBJ anatomy:
v 7.113768577575684 17.32191848754883 17.32191848754883
v 7.126458168029785 17.51559066772461 17.12377166748047
v 7.164247035980225 17.70268249511719 16.92346382141113
v...
vt 0 0
vt 0 0.125
vt 0 0.25
vt ...
vn 0.1874676048755646 0.6945680975914002 0.6945725679397583
vn 0.1794598549604416 0.6956261992454529 0.6956280469894409
vn 0.1714430749416351 0.6966375708580017 0.6966372132301331
vn ...
f 60/11/11 59/3/3 86/2/2 87/10/10
f 51/12/12 50/4/4 59/3/3 60/11/11
f 41/13/13 40/5/5 50/4/4 51/12/12
f ...
However, despite the differences, both don't render properly in Studio; both show the same errors.
From
Wikipedia (where it also says "Vertices are stored in a counter-clockwise order by default, making explicit declaration of face normals unnecessary.")
# List of geometric vertices, with (x,y,z[,w]) coordinates, w is optional and defaults to 1.0.
v 0.123 0.234 0.345 1.0
v ...
# List of texture coordinates, in (u, v [,w]) coordinates, these will vary between 0 and 1, w is optional and defaults to 0.
vt 0.500 1 [0]
vt ...
# List of vertex normals in (x,y,z) form; normals might not be unit vectors.
vn 0.707 0.000 0.707
vn ...
# Parameter space vertices in ( u [,v] [,w] ) form; free form geometry statement ( see below )
vp 0.310000 3.210000 2.100000
vp ...
# Polygonal face element (see below)
f 1 2 3
f 3/1 4/2 5/3
f 6/4/1 3/5/3 7/6/5
f 7//1 8//2 9//3
f ...