Zbrush r3.5 baking polypaint to diffuse issue

ablaine

I spent a few hours trying to work around this issue I'm having trying to bake a diffuse map from my polypainted high res mesh in zbrush... I'm hoping someone here can give me some fresh ideas to try so I don't lose the hours spent painting it.

now, I understand the process of baking the diffuse (as laid out by eat3d), but the issue I'm having involves trying to combine the subtools/apply new guv tiles/create a new texture from polypaint, using multiple subtools which were not imported into zbrush with existing uv info. I've tried using subtool master to merge the objects and generate new guvtiles but it has caused a few crashes to desktop or stops responding.

Is there an easier way to do this? I just want to generate a texture map from my diffuse so I can bake it as a base texture using xnormal.

Thanks!

Bal

You don't necessarily need to merge all your subtools, you can make a polypaint map for each (with guv for instance), then just export those as separate OBJs for your bake, and add each polypaint map to it's appropriate model in xNormal before baking.

ablaine

Hm.. I tried that last night but the final texture came out a garbled mess. I'll try again.

chronic

If you have access to Topogun:
http://www.cgbootcamp.com/tutorials/2009/12/4/topogun-zbrush-polypaint-transfer.html

divi

ablaine wrote: »

Hm.. I tried that last night but the final texture came out a garbled mess. I'll try again.

did you flip the textures?
for some reason zbrush likes it's textures upside down but nothing else likes them that way

ablaine

Thanks for the response. The original problem was that the textures weren't flipped. After flipping them I was able to generate base textures earlier... but now whenever I try to generate base textures in xnormal, the texture comes up as solid colors. I have no idea what's going on. I ensured that I was using the right textures for the correct objects.. the normal map and ao generate correctly.. it's just the base texture which is only showing up as flat colors.

Any suggestions?

And thanks for the idea Chronic, but topogun wont even load my reference model as it's around 12 million polys.

disanski

You could decimated first. That should bring it down to 1.5 million and still looking cool

ablaine

But doing so would remove the polypaint--in the tutorial linked above he specifically mentions that the only downside to that method is you can't decimate it before bringing it into topogun.

disanski

Upps sorry I did not think of that. I am sorry but is it for a game model. Perhaps I am missing something. Are you going to transfer this to a low poly model or is it just high poly?

ablaine

No worries! It's just really strange that everything else is rendering correctly but the base texture renders as a flat color for each object, even though the base textures are loaded in next to the corresponding objects and the textures were flipped on the Y after exporting from zbrush. Are there any options in xnormal that may be causing this?

ablaine

Is there any way to set it up so textures applied to an object in zbrush are automatically flipped on the Y axis when the obj is exported with txr enabled?

divi

you could try to flip it inside zbrush and apply it. will look wrong in zbrush but might work in xnormal. just guessing though

ablaine

Hmm wonder if that'll work.. The texture doesn't seem to override the polypaint in 3.5 like it did in 3.1 so I don't know if flipping it will even be visible in zbrush, but hopefully it exports correctly.

When exporting the high res objs I was turning off the "Txr" option under export settings.. Because it looked like it was exporting the bmps and overwriting textures for that object that I had already flipped and exported. Maybe the polypaint information isn't saved to the obj if I disable that option? Though when exporting it did say "exporting with polypaint"...

I am so confused. Haha

chronic

you can still use topogun if you export you mesh in chunks - maybe based on some polygroups, you will probably have little or no seams, and you can bake the chunks individualy

Pavlovich

Hmmm I'm having the same problem with R3 specifically (it's been a while since I've had to bake off a polypaint). xnormal 3.16.12 just hangs with the new R3 .objs, and 3.16.13 (like you said) doesn't seem to like baking off diffuse maps any more. I'll root around a bit and I'll post back here if I find anything.

Pavlovich

ah...turn txr on under the export options. seems to bake fine (even across multiple combined subtools)