EDIT: So this post here is just a big mistake, but a learning experience nonetheless. tl;dr I did something fairly simple in a very long-winded way.
Okay, so I’m trying to make it so that the antlers are textured just like real antlers would be, so it looks like someone has just bolted a pair of real antlers onto a steampunk deer. Antlers are very worn down at the tips, and are therefore a much brighter colour.
I have been trying to emulate this with my antlers; however, it has been very difficult, as there is no node (correct me if I’m wrong) that will just shade the tip of something, and so I have had to use math nodes and the geometry ‘position’ to isolate the correct part of the antler to be shaded. Here is the setup and the results:
Here I have drawn a diagram which I hope better explains how the tips have been isolated:
However, unlike this diagram, the boundaries do not have an upper edge, and so go on forever upwards in the z direction. This is not a problem.
Here is one portion of the node setup, which gives a bottom boundary, a left boundary and right boundary. If a face lies within these boundaries, it is shaded white. If not, it is shaded black.
As there are five tips to be shaded on each side, there are five of this group, each with slightly different values.
As you can see, there is a problem in that the border between black and white is a solid line. Is there any way of blurring this?
EDIT: After doing all of this, I now realise that it would have been so much easier just to use VERTEX PAINT. This is why you should think about other solutions before you get too bogged down in details.