Hi,

all my (freebie) software rejects the .obj too. However I don't think that the age of the interpreting software has anything to do with it!

Obviously you can't have a negative index into an array of anything, or can you? According to my (ancient) obj reference, wellll, maybe! Have to say that a quick analysis of other .obj files on my HD shows this is the only file I have that actually does this, but;

f 33804/-1 33774/-2 33719/-3 33762/-4 means:

face at absolute index into array of vertices (33804,33774,33719,33762) maps to the texture vertices at - RELATIVE index, in terms of lines into the file of - (-1,-2,-3,-4)

In simpler terms: the "/-" parts of the (f)ace chunk reference the preceding 4 lines, in inverse order.

John