> The problem is when exporting from Moi, the mesher produces a lot of edges. Some
> of them don't need to be creased as they are part of a gently varying surface, some
> do ( IE, the edges formed by 2 intersecting surfaces which do not have G2/G3
> continuity? ).
Hi Crusoe, sorry, I'm still not quite understanding what you're saying....
Information about shared smooth edges (as opposed to sharp) is being written to the OBJ file currently, actually in 2 different ways.
Each polygon face in an OBJ file has a set of vertex normals on it that are used for shading - each face on either side of a sharp edge uses different vertex normals to make a sharp crease there (a break in the shading). But when there is a shared surface normal along that edge (surfaces connected in a smooth-tangent way for example fillets), each face along those edges will refer to the same shared vertex normal, unless you have unchecked welding.
So by examining the vertex normals of adjacent faces, an application can know whether that edge is sharp (different normals), or smooth (same normals).
In addition to this there is smoothing group data which clusters together all the faces that belong to one connected smooth set, this is additional data that an application can use to know about where sharp edges are in the model - there is no sharp edge between 2 faces within the same smoothing group, but there are sharp edges between faces that are in different smoothing groups.
So I don't understand why you think this is a limitation of the OBJ format... This information is included in the OBJ file that MoI writes.
If a target application doesn't process this information it isn't a fault of the OBJ format itself, it means the application needs to look at the data to harvest this information.
> But this high poly count makes hand selection of edges somewhat tedious.
It seems like that's why they should include a feature that puts creases along all sharp edges in the polygon data, but not along smooth edges.
- Michael
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