multi-tile workflow breaks in mudbox ...?

[halfstone]

I'm using the multi-tile workflow as described in the Area tutorial by Brian Freisinger. The UV's have been laid out using 3D Coat initially, and then optimized and distributed among multiple UV tiles in Maya before sending to Mudbox.  

When outputting normal maps with mutlitple tiles, the results are completely unusuable - bright seams, hard edges, a completely corrupt normal map.  The process does follow the tiling correctly - they completely ruin the model. 

I've done test after test, and the only thing that fixes this problem is to re-pack these shells into the 0-1 space.  With every other option exactly the same, it works with a single tile and breaks with a multi-tile. 

Is this something that needs to be fixed in the software, or am I missing something?  I've looked through Brian's tutorial and watched the videos on Digital Tutors and there doesn't seem to be anything that needs to be done for these maps to export correctly?  

[tony.su]

There is not same issue in my computer.

I use Maya 2015 sp5.

So could you zip you mudbox and Maya scene file and then upload it. I will test it for you.

[halfstone]

Tony - 

Thanks.  I have done a number of tests myself, with the results shown on the attached image. 

I will do one more before sending you the model - which is to upgrade to SP5 (I'm currently using SP4, as are all the labs at our school).  

David

[halfstone]

OK - so I had a few conversations with Brian, the author of the tutorial that was posted on this site.  He suggested that I use the first method outlined in his tutorial - i.e., using a separate shader for each set of faces within a given tile, rather than using the "Layered Texture" node.  I did that and it worked fine. 

He then suggested that we just cut out that layered texture altogether - we "daisy-chained" the normal maps by sequentially connecting #2 to the default color of #1, #3 to the default color of #2, etc.  

As long as the placement nodes contained the correct translate information in U and V that correspond to the correct tiles, they line up fine.  

the results are perfect.  

It seems that the answer lies in the Layered Texture node - in some seemingly random instances, the node is broken.  

[tony.su]

Yes, you don't need add nomal map manually. In mudbox, use "send to Maya" function. It will automatically add nomal map on your shader.

 

[halfstone]

I understand that you don't need to apply them separately in Maya when you are working with Mudbox, but there are many instances where the original workflow would be very desirable; if, for example, you are using a different software like zBrush or Mari or XNormal to produce the  multi-tile normal maps - the option to  "send to Maya" does not exist.  It makes a lot of sense to use multiple UV tiles when you want to allocate more texture space to specific areas of a normal map. 

The method described in the tutorial on this site and the one demonstrated in Digital Tutors simply does not work with the  Layered Texture node - It must have worked at some point, or the tutorials never would have been published.  Something has happened to cause the Layered Texture node to fail.  

I think your answer is perfectly valid for the Mudbox forum - but does not  address the larger issue in Maya.   

In reading what I just wrote, it's possible to misconstrue this answer as being ill-tempered or quarrelsome, which is not my intent.  As always, I intend only to find the right answers and to share them with others.  

[halfstone]

I did my own research on this issue, and came to the conclusion that the Layered Texture Node simply does not work for this application.  It must have worked at one point, because there is a tutorial that demonstrates the workflow here, and it has been picked up by Digital Tutors - but it does not work for me, nor does it work for the 36 students in my class.  

Brian (the author of the tutorial on this site) came up with a workaround, which is to copy each normal map into the "default color" of the one before it, essentialy daisy-chaining them together.  This solution works fine. 

However - there is a better option, which was brought to my attention by another user on this forum - Sebastian Freigang pointed out that in Maya 2015 there is a new feature embedded in File Textures which enable them to detect multi-tiles. 

http://help.autodesk.com/view/MAYAUL/2015/ENU/?guid=GUID-132520C0-F1DF-4C74-B8C1-D89154ADFBDB

[paul.kind]

Hello HalfStone,

Can you link me the tutorial?  I'd like to watch try and test this.

Paul

[halfstone]

Sure.  The tutorial is actually on this site - http://area.autodesk.com/tutorials/part_1_multi_tile_uv_mapping

The process in this tutorial works for painted textures, just not normal or displacement maps.  

There is a video tutorial on Digital Tutors here - http://www.digitaltutors.com/tutorial/688-Multi-Tile-Texture-Workflows#play-14422 which uses the same workflow and does include normal maps. 

Contrary to what the title of this post says, it's not a Mudbox problem, it seems to be a Maya issue with the Layered Texture node.