It would be nice if loaders automatically rotated models so they were in the right orientation, if the modelling program uses different axes.
How would the loader know? It's generally the choice of the modeler how they set up their axes.
for example, 3ds uses a Z-up axis. I don't know if you can change this, but if you could, why are all methods on the wiki with rotation?
I think that exportes should give the possibility to change orientation not importers.
For example Blender export scripts are lacking from this point of view, considering that Blender is a rare case of Z-up axis oriented, while most of the 3D engines uses Y-up axis.
Maya, Cinema 4D, Wings3D, Soya3D and many other engines are all Y-up, I am not sure about Lightwave, Softimage, Houdini, but if I remember well they are Y-up. Most of the 3D game engines are Y-up.
So Z-up seams to be a rare case, just used by Blender, 3D Studio Max and some other.
I personally managed to change blender2cal3d so that it can export with the right orientation for jME. But other coders seems to not care this argument. While I think it should be one of the mandatory features of a good exporter.
In jME you are completely free to setup your camera to be Z up, Y up, or even some random ray up. It would make no sense to enforce arbitrary rotations on the models for different importers. Instead, as was said, the exporters or your code should rotate your assets to be in the correct position for your game.
ok ://