Vray for Maya Normal Map Problem
polycounter lvl 8
I'm experiencing the following problem with VRay for Maya.
Looks to me like tangent mismatch between viewport 2.0 and VRay.
I'm rendering in Maya 2017. I'm using VRay version 3.52.03
The Normals on the mesh are completely soft and "unweighted".
Can anybody tell me of a workaround or checkbox to get this fixed without changing my content ?
For example in Mental Ray there is a option called export Maya Derivatives, that matches the renderers tangents to that of Maya.
Any help is appreciated!
Replies
I dont mess around with offline rendering too much nowadays, but have you tried looking into the colour space for your normal maps?
The standard file2d node in maya usually has it set to sRGB, you want to set this to RAW for your normal maps.
I noticed that when I did play around with offline rendering the rendering engine had some custom colour space management for the textures. (Note I wasnt using Vray, so might be different for Vray.)
After a quick google i found this article:
https://docs.chaosgroup.com/display/VRAY3MAYA/Color+Management+with+V-Ray
Talks about exactly that, colour space management for Vray.
test Scene
I've also experimented with triangulated vs quads. And made sure the map is set to "Raw" colour space.
I'm trying to figure out how to get the normal map consistent.
Viewport 2.0, High Quality Viewport and Mental Ray are all consistent.
VRay and Arnold are giving me different ( vissually wrong ) results.
In the past I also noticed Maya Viewport Normal Maps aren't in sync with Mudbox Viewport Normal Maps.
Dont have access to Vray, but maybe this will help.
When I unlock the normals of your mesh I get results like your Vray render inside of the viewport, on your triangulated mesh. (lower right)
On the other 3 meshes, when I triangulate them, I get similar artefacts like your Vray render.
So to me it looks like 2 things are happening:
1. You did not triangulate your mesh prior to baking, as there are some 'X" normal map artefacts.
2. Vray ignores the normals of your mesh and recalculates them when rendering.
I did render those normal maps without triangulating.
Because you don't have VRay I made a quick render of my test scene, viewport 2.0 versus zbrush IPR
The triangulation has some a lot effect but as you can see from the lower left one there are still some artifacts that look to be unrelated to the triangulation. It also looks like Vray respects "locked normals"
But as you can see from the previous image on the circular element there is another mismatch that is not explained by triangulation. Maybe tangent space is MikkTspace for one, and something else for the other one.
But yeah from what I gathered, most offline render guys do not actually use normal maps much. Most of the time they still go with bump maps.
(Literally only saw one guy mention this somewhere in relation to Arnold normal maps.)
It could very well be that they indeed use different tangent spaces.
I guess you could always try to bake a bump map? =P
I'm a bit
I just assumed this was Normal because MTR supported them just fine.
But since Nvidea killed Mental Ray, I'm looking for a replacement.
Both Arnold and VRay looked like an upgrade, but non of them have propper normal map support. wth ? It's 2017 XD
There is also no documentation anywhere on what tangent space they use, so I can adjust my baking process acordingly.
PS : I'll double check that one piece of geo in the bottom.
If you find anything specifically for Arnold let me know though! =]
However you can still get MentalRay from Nvidia right?
https://forum.nvidia-arc.com/showthread.php?16283-Now-Available-Mental-Ray-for-Maya-2018
I've just downloaded and installed it. Did a super quick test in Maya and it seems to work just fine?
Btw I sent you a pm, did you get a chance to look at it? =]
But before each render it takes an enormous amount of time caching all the textures. ( converting it to .map formats for faster load times )
Both Arnold and Vray have found smarter workarounds for this. So for quick lookdev mental ray is really fighting me.
One workaround would be if I could figure out a way to avoid those long loads for my textures. That would bring it up to par with Arnold and Vray
I'm in touch with the Arnold helpdesk about the matter. I'll keep you posted in case we manage to get the bug resolved.
I'll take a look