I am getting some sort of stepping/banding on my water surface - I am using a Vray displace modifier set to 3D mapping. I have tried tweaking all settings but can’t seem to fix it.
I am using a map that is made up of procedural noise and smoke maps and using mix & masks to blend them - coordinates are set to object XYZ.
Any thoughts?
this looks like typical banding when using an 8 bit image in displacement. Do you have any 8 bit maps there? otherwise, it can also be that one of the procedurals is not mapping correctly, i.e. the coordinates produce weird artifacts. You can plug your maps one by one into a vray light material and render without displacement to just see how the maps look in the frame buffer.
Thanks for your reply Dmitry - there are no images used, they are all procedural so can’t understand why it is happening. I will have to try what you have suggested and strip them back one by one.
Hello Chris!
rather than using displacement you can try this free plugin
http://www.guillaumeplourde.com/index.php?cID=75
It is for Houdini but it works for max 
There is a bug in the 3ds Max Noise texture that leads to this type of banding. You can try other noise textures, e.g. Bercon maps, which do not have this issue.
Best regards,
Vlado
Aha thanks Vlado! Do you know if the smoke map is ok?
Thanks Chris - I’m too far gone now to switch my water setup does look good though! how does it tile over large areas - as this was always an issue with dreamscape…
I’m not sure; I’m afraid it might be an inherent issue in the 3ds Max noise generator (which is used by most procedural textures).
Best regards,
Vlado
hmm, anyone know a way around this without installing 3rd party procedurals?
vray rt does not seem to produce the banding though, any tips on what vray setting i could tweak if i wanted to mimick the vray rt behaviour?
It might be possible to cook a VRayGLSL texture that does something similar (GLSL has a built-in noise function). Are you just using the Noise texture?
vray rt does not seem to produce the banding though, any tips on what vray setting i could tweak if i wanted to mimick the vray rt behaviour?We coded all the textures for V-Ray RT ourselves, so we were careful to avoid this issue.
Best regards,
Vlado
ah, so vray rt procedurals are actually chaos code? that explains it
we are using the smoke texture a lot for ocean surfaces, and this issue really causes a lot of trouble.
it doesn’t seem like there will ever be a fix from autodesks side, so any help, tips or cooking from you guys would be so very much appreciated.
what did you have in mind regarding the VRayGLSL texture? i have not had the chance to try it yet, and this sounds like an excellent opportunity.
The standard max noise map works fine. It´s the smoke map that produces the bending because it´s just a 2d procedural.
This was more obvious in previous max versions before slate where you could see if it ´s 2d or 3d.
Try Bercon Maps, they own every 3dsmax procedural anyway
Also you can try a Cellular Procedural in circular mode with inverted colors.
Want to post the max file? I have done a fair amount of displacement with the built in noise with no issues and the built in noise function in the sdk are clean other than the issues with the second order derivatives.
I’m interested to see whats going on that its so visible an artifact.
-Michael
sure, there’s a stripped down max file attached. the difference between vray rt and standard is quite a thing.
samuel, the bercon maps are great indeed, but we want to keep plugins to a minimum if possible for compatibility reasons. inverted circular cellular sounds interesting, but maybe a bit complicated to produce a smoke map?
i really like the GLSL idea, but must say i am pretty fuzzy about how to go about it, anyone know a good smoke algorithm?
hah! that is cool samuel, i’m gonna have to look at the inverted cellulars, i wonder how it animates. and yes, agreed about the bercon maps, we’ll have to consider bringing them aboard again
wow, i just had that illusion again, when noise suddenly seems to go inverted…more coffee!
Hello Vlado,
that leads me to the question, would it be possible to integrate this self coded textures into V-Ray Advanced too?
If you’re too far gone to re-do the maps, it’s due to the scale of your largest procedural - if you have a few of them being mixed together, you can have 3 of them at scales of 5, 10, and 15, and another one scaled to 60000000 - and it’s that one that’ll produce the stepping issue. Dropping the size of your largest one might be enough to scale it down where it’s less of an issue. I replaced my huge one with a clouds bitmap from photoshop in another mapping channel and the problem was barely visible.
I can also confirm it happens with all procedurals in max - some just don’t need to be used at the same scale as others so it’s less visible.
This is also why some people haven’t seen it. If they take one that works, add a noise in a mix at 1% scaled to something crazy huge and render the same issue will come up.
