Emission Shader on edge

[Marvel175]

Hi. I am trying to create a Star Wars-inspired Darksaber, but I can’t get the blade to work. In other words, how do I make the material so that the blade is black in the center but emits light on the very edges and the light adapts to the camera’s position? Thank you.

[stray]

Hello and welcome to BA!

This sounds like a job for… the “Inverted Hull” method.

Daily Blender Tip 254 - Easy outline with the inverted hull method (Blender 2.8)

Only instead of traditional dark outline you can use emission material:

[joseph]

Welcome to BA
Something like this should get you started:

Step 1

Step 2

Everything in the node group is the nodes from the first screenshot.

Step 3

Step 4

Similar nodes to step one.

Step 5

Connect steps 3 and 4:

Step 6

Connect everything with a simple Math node:

Step 7

Change these to 4D instead of 3D. Type #frame in the W slot. Press spacebar, watch the magic happen!

Or, what @stray said, if you want something faster and simpler

[Marvel175]

Thanks. However, in Blender 3.3, there is no backface culling option in Rendered View, so it doesn’t work properly. Did that setting move?

[stray]

You can find it in Material Properties > Settings - it’s unique parameter for each material. Checking it just for outer material should be enough.

@joseph, ooh, fancy - I like it

[Marvel175]

Thanks. It worked perfectly. And I distorted the emission with some noise and animated the position, which gave it a cool effect.

[Marvel175]

This is a little confusing, but I will keep it in mind for later. Thanks!