TL;DR Just want to add rim light to the edge of a mesh without using fresnel/layer weight, since it doesn’t work
Hello! I’m trying to model a certain sword from a certain game. I was wondering how would one create glowing rim light like this glass ball, on a more complex mesh without using the fresnel/layer weight node. As an example, notice how the rim light constantly stays into the edges, while the center is transparent.
However, this doesn’t work on more complex meshes through using the fresnel/layer weight node, as the node isn’t able to properly read where the edge is. As such, I get a fresnel that’s right in the middle (the red arrows), which isn’t what I want.
I simply would like to have a rim light around the edges of my mesh, with the middle unaffected, like that crystal ball. Here’s what in-game version looks like (notice how there’s a glow only on its edges, with middle unaffected, like I’ve drawn with the arrows)
It’s creating the exact some problem (Layer Weight/Fresnel not reading the outline properly) I mentioned earlier. Both are pushing the light to the extreme ends instead of the overall outline.
I have no idea if this is stupid, but maybe changing/mixing/blending the material on the edge to emission could help? I still know next to nothing about nodes.
Fresnel effect is relative to normal. If faces of mesh are facing viewpoint, there is no effect. If there are oriented in an other direction, the effect is noticeable.
That means that you would have to bevel edges of geometry to see an effect.
An other technique is to use a cavity map or Pointiness to emphasize sharp edges.
But that means to use Cycles or/and to modify geometry, too.
To me, your object looks like a mesh, with a simple extrusion, maybe done with a Solidify modifier.
In that case, best choice is probably an UV texture.
Unwrap faces to obtain a ribbon of UVFaces. And with that, UVmap a gradient on the width of ribbon.
But the reference you are showing corresponds to a geometry a lot more round, on which Fresnel effect should give a correct result.
So, fresnel effect does not work, not because geometry is complex. It does not work because geometry is too simple.
I have done this a few times, but I usually will select ONLY a thin section of the object and apply an emissive shader, or Duplicate an edge and do the same ( an edge will glow but not show in a rendered view. It’s a Hack but works…
For instance this Katana. The OP wanted a blue Glow on the edge of the katana ( he also wanted to animate up from the hilt to point and start without a Glow hence the Mapping node )… The part is just a thin sliver I selected and added in the new material, for the emissive.
) !
