Technically speaking, hard edges is just a special case of normal cluster
where the specific normals associated with the edges are not smoothed via
smoothing/discontinuity/etc... They are left in their original raw state
(perpendicular to surface). You do not need to create "hard edges" to have
the same end result of faceted edges on the mesh. You only need to know
which normals in the normal cluster should be interpolated vs. not.
Normals live on samples (or 'polygon nodes' for the specific case of polygon
meshes), which are the original unshared vertices of the mesh. If you want
to preserve hard edges coming from Maya, you'll need to keep track of the
sample indices and make sure they don't change during the transition. If
the samples change order, then your backup plan is to record the vertex
index and polygon index together in Maya and pass that along as metadata to
Softimage as that'll be needed to identify which sample on a vertex should
be flagged for hard edges (because each vertex in Softimage has multiple
samples).
If polygon indices change too, then the only brute force method available is
to unshared all the edges of the mesh in Maya to force the vertices to be
unique so when you get them over to Softimage it'll be easy to identify and
flag...but of course unsharing on it's own will force hard edges on all the
unshared edges so in some ways will defeat the purpose.
An alternate non brute force method (if all the indices keep shifting
around) is to apply a vertex color property or UVW texture projection and
record the edge flags there, then have a plugin in Softimage read that data
and apply the hard edges. A little clunky, but perfectly functional as I'm
pretty sure vertex colors and texture UVW coordinates are properly
converted.
Matt
Date: Sat, 11 Apr 2015 19:31:06 +0900
From: Martin Yara <furik...@gmail.com>
Subject: Hard edges from Maya to Softimage
To: "softimage@listproc.autodesk.com"
<softimage@listproc.autodesk.com>
Hi list,
Is there any way to export hard edges from Maya to Softimage as hard edges
(not normal clusters) ?
I though about getting a list of edges from Maya, but when I import the
data in Softimage the edge numbers change and differs from Maya. Vertex
indexes are the same though.
Or better, is there any way to convert those normal clusters to hard edges?
I have to convert character scene files from Maya to Softimage and right
now I'm redoing all the hard edges in Softimage and it is quite time
consuming.
Thanks
Martin