Yet another thread inquiring as to why a .mtl isn’t loading with an imported OBJ file. How do you fix this?
Hello - one thing we’ve encountered is that some mtl files include RGBA colors - Rhino is looking for RGB colors and bails when it sees four numbers. These are now supported in V7 but in V6 you’ll have to modify the mtl file in a text editor to remove the last number if colors are given as RGBA:
Kd 1 1 1 0.75
should be
Kd 1 1 1
If that is not it, please post an example here or to tech@mcneel.com, with a link back here in your comments.
-Pascal
@ethanj.fx … aka tech@mcneel.com 
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