Export OBJ mesh issue

Hello !

Little help needed

I have an issue with exporting mesh in OBJ format from Rhino 7. Before exporting the mesh I hit preview to check the settings and mesh looks OK, but when I import exported OBJ mesh back to Rhino, it looks really bad, and strange artifacts shows up, like quad remesh… I´m posting screenshot:

I also checked the NURBS model, and it looks OK, no naked edges or any errors. I tried even export it to FBX and it works OK, STL too, only problems are with OBJ format…

Thanks
Tom

fragments:

Hi Tom,

pls. provide _SystemInfo and an example file that shows this behavior, thanks. If it is confidential you can upload it here with a note to this thread.

Hi !

I send the data, to the link you provided.

I find the mistake… :slight_smile: I used batch export script that exports each layer as OBJ object, and it change the default export settings. The script changed significant digits to “4” and this cause all the issues…
I reverted the value back to “17” and it works like before…ufff

Do you know what this settings means “significant digits” ? because it dramatically change the quality of the mesh, even when davanced settings like distance from edge to surface, maximum edge lenght, is set to make high poly mesh, it ignores this settings.

That is how many digits are written for each number. The center of your object is about 3500 units from the origin, and, when using 4 significant digits, anything behind the decimal separator will be dropped.

OBJ files are plain text and you can open it in Notepad to see how the values are written:

Rhino

g Default
v -270.5 -2856 1729
v -270.5 -2857 1727
v -270.5 -2859 1727
v -270.5 -2860 1726
v -270.5 -2861 1726
v -270.5 -2863 1726
[…]

-wim

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