Devising a  visualiser for a sculptor friend I have written an application which displays two intersecting spiral planes, one clockwise and one anticlockwise. I have the planes displaying correctly, but the materials and colours are completely different.
In true Java fashion I have an interface which accepts the dimensional data for the two spirals and I build the geometry and  appearance in two instantations of the one class ( SpiralPlane ), passing the separate dimensions sets to each, via the constructor.  The geometry is different for each as dictated by the dimensions using GeometeryInfo class to construct a Triangle Strip Array each time the class is called. The Materials Node Component is the same for each call, but they display differently!
e.g. I get one gold spiral, which is correct for the values set, but the other spiral appears as black velvet. The selection of the colours and shininess is fixed in the class and not passed to it from elsewhere.
 
I have run many different options, such as cutting off one or the other spirals, with no effect I still get the same spiral displaying the same effect, but now alone on the screen.
 
The two shapes are children of children of separate TransformGroups, both children, in turn, of the a common BranchGroup. The lights ( 3 ) and the background are further up the scene tree.
 
I believe it is the lighting, but I cannot explain it further. Enabling the emissive colour of the  Material and  lights up the "black velvet". Without enabling the emissive colour there is a hint of reflected light, but the effect looks as though there is a very small shininess value.
 
By the way, I like the effect, but my sculptor friend will be  not impressed by my input into the "creative" end
 
Peter S.
 
 

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