Dunno, but you may want to look at xom.xith3d.test.Xith3DTexCoordGenerationTest.
Yes, with Xith3d environment mapping is very easy to use. Compared to a normal texture mapped Shape3d you just have to add two
further lines. Like in the above mentioned Test:
Texture2D textur = ...
TexCoordGeneration envmap = new TexCoordGeneration(TexCoordGeneration.OBJECT_LINEAR, TexCoordGeneration.TEXTURE_COORDINATE_2);
Geometry geo = ...
Appearance ape = new Appearance();
Shape3D korpus = new Shape3D(geo, ape);
Many commercial games use Environment-Mapping to fake a kind of reflective surfaces, like Jeff said. And indeed it looks pretty good (for example Startrek Voyager Eliteforce II uses it all the time).