5,4,3 instead of 6,5,4 

according to NIMBLE save_textured_nimble function in 
https://github.com/reyuwei/NIMBLE_model/blob/7d01621b30359e8d7e225cb6f2ee2148c9aef0a2/utils.py#L347

the normal map is the 3, 4, 5 channels not 4, 5, 6 and the spec is the 6, 7, 8. Is this a mistake? 
https://github.com/korrawe/harp/blame/ea9d46505aa6d0b4a30066f55ddbe2c61e7e23b0/utils/visualize.py#L79