Backface lighting

[CodingMadeEasy]

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. 

[Nabroski]

Hey i saw your previous Question on the Clone Light
maybe this will help you, i also use backface culling

Video:
https://a4acc9b70392159f933adb66ef2d77dccf170c21.googledrive.com/host/0BwTQLXGKzDbZYVR5RHc5NGVvU00/

Playground:
http://babylonjs-playground.com/#27G647#1

Good Luck

[jerome]

http://doc.babylonjs.com/classes/2.4/Mesh#flipfaces-flipnormals-rarr-void

[CodingMadeEasy]

Hi. Thanks for the reply. I figured out the problem with the cone problem. Now I just want to know how to get light to reflect off back faces.

[Nabroski]

Hello
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
http://www.katsbits.com/tutorials/blender/double-sided-faces-different-materials.php
unity code
http://answers.unity3d.com/questions/280741/how-make-visible-the-back-face-of-a-mesh.html
 

[Kesshi]

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.

[V!nc3r]

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.

[CodingMadeEasy]

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?

[GameMonetize]

Hello

you can deep copy a mesh with mesh.makeGeometryUnique()

[CodingMadeEasy]

Awesome! Thanks