Hi there

I want to convert an obj file into an ase file without using 3dsmax. The obj file only contains vertices and triangulated faces. The ase file should contain vertices, faces AND smoothing groups. The smoothing groups should be applied in the same manner as 3dsmax when using the auto smooth function on an object with treshold = 30 degrees.

At first I thought it was straight forward. I
1) load the obj file
2) calculates normalized normals on all faces.
3) if two faces share normals that has an angle below 30 degress, they go into the same smoothing group, else seperate ones.
4) save ase file

After doing this, I found out that I get a lot of smoothing groups (more than the 32 available). Furthermore some edges are still smoothed even though the faces on both sides of the edge are contained in different smoothing groups (e.g. smoothing group 2 and 3). That makes me wonder if I have understood the smoothing group term correctly?

What would be the correct way to calculate the smoothing groups similar to the ones calculated in 3dsmax?

Thanks a lot in advance.