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i import one irr file generated by irrEdit into irrlicht,and set mode scale to be (20,20,1),i found sometimes x-scale doesn't work,sometimes it works then i reset the project(close-open),badly it won't work again.
I'd say that this is highly unlikely, maybe something else happens with your mesh?! The setScale function is completely ignoring mesh types etc and is working with a least basic functionality from the driver. Can you show the full code to reproduce this problem?