Mudbox - black border around AO bake

TorQue[MoD]

Hey all, so I tired posting this in the autodesk forums but its really dead there...

I've been using Mudbox for years to render out the Normal and AO for my terrains. Something I've never been able to figure out is that any time you render out an AO in Mudbox (this has been present since 2012) there's a black border around the outside edge of the texture. I've tried adjusting the UVs on the plane so they go right to the edge but this doesn't make a difference. I've also tried a google search but its never turned up a solution. Any ideas what's causing this? 

TorQue[MoD]

No one here knows either huh? 

oglu

have you tried a different graphics driver..?
mudbox is baking ao with the GPU...

are you using mud 2016 ext1

repete

I had this issue a few years back and from what I can remember it was and UV issue. My height maps where coming from world machine btw.

I did get it sorted but I can't remember how but it was definitely an issue with the UV boarders. 

repete

This might be useless but worth a try: http://forums.autodesk.com/t5/community-help/black-borders-in-ao-maps/td-p/4127329

TorQue[MoD]

Pretty sure its not the GPU. As I said the issue has been happening for years and I've had new hardware since then. Actually I'm only running Mudbox 2014. I originally thought it was a UV issue but as I said, it happens while using the default plane in mudbox or with my custom plane and fixed UVs where they are perfectly aligned with the edge of the UV space. I don't think it is a UV issue though because you can still see the proper AO underneath the black outline when you bake at a higher resolution. Its like its a black border being multiplied across the image. Really weird.
Deleting the settings folder only caused Mudbox to crash at start after trying to set a new data folder. Deleted that too and... it made absolutely no difference to my bake.
Like I said, I've tried to figure this out for years without ever making any progress. Sad too cause I love how fast MB bakes maps. I usually don't care about the border because its only on the part of the terrain that no one will see anyway but the OCD in me loathes it :P

oglu

could you share an object which bakes with the black border...
id like to have a look...

TorQue[MoD]

Hey OGLU, apologies for the late reply... I've been a bit busy lately. Here's a sample scene: http://www.torquemod.com/AO_Test.zip

oglu

bakes fine on my geforce 960...

TorQue[MoD]

Weirdness. I've always owned Nvidia cards and as I said the issue has been happening for years. Normals bake without issue but the AO maps always have the border. Ah well, thanks for the attempted help :P Guess I'll have to wait till the next video card upgrade to see if it still persists. I'm running a GTX 780 right now.