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Backface lighting


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I'm trying to get lighting to work on the backface of a mesh, but it doesn't work. After reading through the lighting tutorial, it seems like it's not possible due to the normals. I was wondering if there was any trick I could use in order to get light to reflect off the opposite sides of a mesh. 

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im no fully understand what you are trying to achieve. 
if i lean back for a secound and think about back and front faces,
backfaces are normaly (unseen, skipped) in graphic engines to get more resourceses for stuff that matters - what is visibel for the user, the frontfaces. 

If you want to do in the hard coding way you have to duplicate and flip the faces (from my logic point of view)
this can be done by babylon - easy, its made for this.

here is a link, i found using a popular search enige, for blender
unity code

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In the the old days of fixed function OpenGL you could enable two sided lighting ( glLightModelfv(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE) ).
If you want to have two sided lighting now, you have to duplicate your faces and change the face-winding and normal of the duplicates.

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You can do the tips that Nobroski linked, but i don't like this, due to overlapping faces. it's much more simple if you just model faces that you want.

If you want to set a thickness to a plane, in blender apply a solidify modifier, in 3dsmax apply a shell modifier.

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Thank you all for the help. It's greatly appreciated! :).


Edit:  One more question. I've attempted to apply the method of duplication then flipping the faces. I used the mesh.clone method to do so, but it seems as though the vertex data is shared and therefore when mesh.flipFaces is called, it flips the faces of the source mesh as well. Is there a way to do a deep copy of a mesh?

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