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As I had much fun with this (thx Chebhou) but gaussian functions are a bit too complex for me, i want my volume scatter cylinder to have simply a smaller cylinder emitting light inside it, from the same object/material. The same size all along, or why not being able to control the fading at one or both sides (why not asking :) )

It has to be done with math nodes, vectors and things like that (what I want to learn)

Something like this but in a single object enter image description here

looks like a light saber :)

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Bithur
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  • related: http://blender.stackexchange.com/a/15711/1853 and http://blender.stackexchange.com/a/3640/1853 –  Feb 13 '15 at 17:11
  • @cegaton nope, i don't want a compositing or modeling answer, it has to be shader maths. I already did (long ago) a light saber but i want to learn more about math nodes and vectors in materials. I hope this is simple enough for me to understand the why and how. – Bithur Feb 13 '15 at 17:16

2 Answers2

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use this circle equation and chose a radius "max R = 0.5" :

enter image description here

Coordinates node group : enter image description here

and for fading on the sides i used a sin function :

enter image description here

render : enter image description here

Chebhou
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Variation on Chebhou's answer : Origin and dimension independant :
enter image description here

Not sure the sine works exactly the same.

Bithur
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