I did one of Ryan King Art’s tutorials on YouTube, specifically the one for the Procedural Asphalt tutorial. Unfortunately, the material doesn’t look correct to me.
I used Blender 5.0.1 for the software, and Ryan’s video is a few years old (making it a previous version of Blender he used). I’m sure there are a few things I need to fix; I’ve already updated the Bump Node so that becomes more clear. Unfortunately, I’m unable to see rocks or pebbles in the finished texture. Does anyone have any suggestions on how to fix my texture?
First things first. What IS correct? Do you have reference?
Is this correct?
or this?
or this?
or this?
or which one out of millions of possible ways it can look are you trying to make?
Another thing is: you don’t see it in balls usually so you might want to look at it on some surface that resembles a road or something so you can compare the results to something real.
I do admit mine looks like cracked asphalt. I just don’t see the pebbles in the asphalt, created by the bump map. And yes, asphalt doesn’t come as a ball shape - the tutorial called for using an ico sphere with a subdivision of 6 and shaded smooth.
Maybe I should try it on another shape. Maybe I’m just being picky, thinking it isn’t good enough.
Have you tried applying the scale of the object? And I kinda understand that Ryan King uses icospheres, they are a common way to demonstrate materials because you can see the result from different angles and shadow border automatically.
I mean if you have a more concrete realistic goal in mind(I mean images, it’s just as easy to find 100 different looks of cracked asphalt…) it might be easier to suggest something to improve it.
If you work on a material, you should generally have some reference. Other way, how can you work on it?.. It’s impossible to make a material if you don’t know how it is supposed to look…
I got the file fixed, as well as the material in my asset pack fixed too. I accidently plugged the Bump Nodes up Tanget instead of Normal, and I didn’t realize it. I fixed it.
I added the material to a cube in my asset pack/asset library so it would be on some sort of flat surface. Asphalt cubes aren’t realistic, but it’s good enough for me.
With IOR Level completely zero’ed out, roughness have no meaning since it applies to specular. In rendering terms, asphalt is a very porous material with tons of cracks and “pores” that traps the light and prevent specular energy from being reflected. So I’d use a modulated (mapped back to 0-1) version of the albedo map to also drive IOR Level, say from 0.001 to 0.35 (maybe as much as 0.5 in some cases).
The old “excessive bump into diffuse only” trick isn’t how we approach PBR today. There really are specular reflections on asphalt, the brightness that is there (on black/new asphalt) is pretty much from specular reflections alone. That’s why it becomes much darker when under water; the water/asphalt IORs are much closer than asphalt/air interface, significantly lowering the effective IOR.
Dry effective IOR 1,5 (asphalt) / 1 (air) = 1,5.
Wet effective IOR 1,5 (asphalt) / 1,333 (water) = 1,125.
For a home demo, just put some shiny black leather or shiny black bubble wrap under water in a sink basin and see it’s specular reflections almost disappear. Or the old physics demo where silicon balls become invisible in water due to matching IORs. This is something to consider whenever the Coat layer is used as well, Blender doesn’t lower substrate IOR automatically based on coat IOR, but always uses air IOR; we have to manually do it.
Note that this interface stuff only happen (at least to a visible degree) for dielectrics. Metals remain unaffected and reflect just as much in water as above. Thought I’d try to grab a picture of it, but didn’t turn out too well:
Main light source from above, and the “bubble plastic” thingie goes nearly completely invisible below water, since it’s mostly visible through its specular reflections above.
And I kinda understand that Ryan King uses icospheres, they are a common way to demonstrate materials because you can see the result from different angles and shadow border automatically.
