See screenshot. These 3 objects (close up of banquet seating) have the exact same material on them, except the furthermost left one. The only difference with that one, is the jpeg used for maps are also plugged into UVW Randomizers.
It looks to me as if the normal map is being inverted when plugged through the UVW Randomizer. Which in turn is making it “shinier”. I’ve no idea if thats because of the inverted normal map or if it’s also inverting any of the other maps i.e. bump, gloss etc.
Could it be that you plugged randomizer in incorrect order? AFAIK, its correct position is between normal texture and Corona normal node. It also could be a mismatch between different maps. Double check if every randomizer is absolutely the same, including random seed parameter.
Shader tree attached for both materials. As you can see there is a UVW Randomizer for the ‘smudges’ on both materials. Other than that, all I’ve done is add additional UVW Randomizers for the other maps.
All UVW Randomizers have the exact same settings.
Top material is the furthest left object, bottom material is the 2 objects on the right.
You need to swap places trilanar with randomizer. Correct order is uvwrandomizer->triplanar->material. But i’m not sure if that’s the cause of the issue, because that mistake is in both materials. Other than that, everything looks correct.
To be honest I could get rid of that smudges layer. In the composite, the layer opacity is set to ‘10’ so it’s definitely not that, but good to know it’s in the wrong order.
Is there any info about this in the Corona documentation? I’ve been having similar problems when not connecting maps in the right order.
On the other hand I wish it was possible to connect these maps in any order without this being a problem.
Also, as mentioned in other posts, it would be great if we could connect a single ranomizer/triplanar map for all textures instead of needing one for each map. Just like in Vray.
Just running some tests with random normal maps. It seems related to the W Rotation of the UVW randomizer (either that, or i’m not understanding something about how normal maps work).
2 screenshots attached. Only difference between them is the one that looks ‘inverted’ has the W Rotation ‘To’ value, set to 360.
Edit: Now that I look at it on this example, it seems it’s just the light changing direction as the normal map rotates, noticeable on the distant spheres, a downside to normal maps perhaps, an optical illusion??
That’s correct, when you’re rotating normal map, it’s the same as if you’d rotate mesh normals themselves. No doubt this will give you all sorts of weird illusions. It is best to leave W rotation alone and stick to U, V randomization only when normal maps are involved.
Wow, this is kinda mind-blowing to me. Obvious now that I think about it, but it shows I’ve been doing things very wrong ever since the UVW randomizer came around.
So what I’m understanding from this is that there isn’t actually a way to truly randomize the textures in a traditional format? If I have a diffuse map that matches the normal (ie; wood grain) I can’t go and randomize the diffuse W value as this means I’d also have to randomize the normal map W, which results in wrong normals?
I’d either have to revert to bump (greyscale) maps OR not randomise, OR only randomize non-critical elements (such as smudges)?
For starters you wouldn’t want to randomize rotation of the wood texture regardless of presence or absence of normal map. It’s highly directional texture and would look weird if it would be oriented randomly. Anyway, i don’t see that as a problem - i use randomizer a lot and i almost never rotate the textures, even if they are simple black and white grunge masks. I find that simple U and V shifting is giving me enough randomization and there’s rarely a need to use rotation.
Just to update things - apparently the solution to the issue is to keep correct order of nodes. Corona normal node must go before UVW randomizer, which must go before triplanar. More information about this can be found at Chaos support portal: https://support.chaos.com/hc/en-us/articles/13800753963537
