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FBX vs OBJ Bake

MartinCZ
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MartinCZ vertex
Hello!

I have always used FBX format for baking my normals but i wanted to switch to OBJ because the time it takes to bake is much lower. As you can see in the screenshot, i get very strange ''artifacts'' when i use OBJ with same settings as with FBX. Does anyone have i idea how to solve this problem?

Thank you!

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  • pOgOstyle
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    pOgOstyle polycounter lvl 8
    You got an solution and want to switch to an outdated .obj workflow...
    It could be more usefull to talk about your real speedbenefits from .obj for baking in 2018. About how much time we talking ?

    Edit: ok just in case you taling about the HP - i never got problems like this before. Which software do you use for export and baking?

  • MartinCZ
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    MartinCZ vertex
    pOgOstyle said:
    You got an solution and want to switch to an outdated .obj workflow...
    It could be more usefull to talk about your speedbenefits from .obj for baking in 2018.
    When i have to bake 20 uv's, i like to do it with OBJ format so i dont need to wait 2 hours to bake all my maps. But i was also very curious why this happens with OBJ because it only happens with round objects.
  • Mark Dygert
    Without having access to the meshes and the software you're using it's hard to diagnose. Off the cuff, OBJ is a giant pile of crap that hasn't been updated. If you're using 3dsmax there are several problems with their OBJ exporter which was  upgraded to a popular plug-in but hasn't been kept up to date either, before that it was TOTALLY broken and thoroughly abandoned as FBX picked up strength. 

    If I had to guess, it is probably not handling smoothing correctly and OBJ is physically breaking the mesh along UV or smoothing seams which causes the baking cage/offset to skew in a weird way.

    Some apps have obj export settings you can tune but you never really know how it will be read until you do a bunch of trail and error.
    You can try importing the object back into your 3D package and hopefully you can find out where it is different from the original file.

    TLDR: Obj is a dying format, don't expect anyone to update it.
  • MartinCZ
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    MartinCZ vertex
    Without having access to the meshes and the software you're using it's hard to diagnose. Off the cuff, OBJ is a giant pile of crap that hasn't been updated. If you're using 3dsmax there are several problems with their OBJ exporter which was  upgraded to a popular plug-in but hasn't been kept up to date either, before that it was TOTALLY broken and thoroughly abandoned as FBX picked up strength. 

    If I had to guess, it is probably not handling smoothing correctly and OBJ is physically breaking the mesh along UV or smoothing seams which causes the baking cage/offset to skew in a weird way.

    Some apps have obj export settings you can tune but you never really know how it will be read until you do a bunch of trail and error.
    You can try importing the object back into your 3D package and hopefully you can find out where it is different from the original file.

    TLDR: Obj is a dying format, don't expect anyone to update it.
    Thank you for your response. I'm using Headus Uv Layout to Unwrap my meshes and if i have 10+ uv's then i like to use OBJ because my HP and LP are not in sync when baking them as FBX. I have to once again use Reset Xform which does crazy things to HP meshes.
  • Eric Chadwick
    Put the bake software in your topic title pls!
    http://polycount.com/discussion/63361/information-about-polycount-new-member-introductions/p1#use

    Use Meaningful, Specific Subject Headers


    When posting a new thread, consider the subject header carefully. The subject is your opportunity to attract people to your thread, so it's in your own best interests to use it properly.

    Stupid: HELP ME!!

    Smart: Help required with getting model into UT

    Smarter: UT model exporting issues - model is wrong size.

    Some excellent info here: How To Ask Questions The Smart Way 

  • Mark Dygert
    MartinCZ said:
    Thank you for your response. I'm using Headus Uv Layout to Unwrap my meshes and if i have 10+ uv's then i like to use OBJ because my HP and LP are not in sync when baking them as FBX. I have to once again use Reset Xform which does crazy things to HP meshes.

    Ahh Uv Layout, it's was nice back in the day but there isn't much that it does that Max, Maya, Modo and even blender, don't do. Almost all of the Headus features are standard now. I stopped using it about 5-6 years ago, importing and exporting to a 3rd party app was a pain in the ass, especially with obj butchering your meshes. 

    The fact that it still only works with obj files, just shows how old and unloved it is by its creator. What is so must have about UvLayout that other apps can't do?

    As for your baking issue, more than likely the pivots for the high and low poly aren't in the right alignment, which is why resetting xform probably fixes the issue, but that is like using a nuke as a fly swatter. Still your high poly meshes should be able to withstand a reset xform without going haywire.

    Since it is probably the pivots, you should try turning on affect pivot only (in the hirearcy tab) then snap the high poly pivot to the low poly or vice versa. 
  • SnowInChina
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    SnowInChina interpolator
    i would love to make some nice comments about .obj
    but for me it tends to mess with normals from time to time, so... *sadface*
  • MartinCZ
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    MartinCZ vertex
    MartinCZ said:
    Thank you for your response. I'm using Headus Uv Layout to Unwrap my meshes and if i have 10+ uv's then i like to use OBJ because my HP and LP are not in sync when baking them as FBX. I have to once again use Reset Xform which does crazy things to HP meshes.

    Ahh Uv Layout, it's was nice back in the day but there isn't much that it does that Max, Maya, Modo and even blender, don't do. Almost all of the Headus features are standard now. I stopped using it about 5-6 years ago, importing and exporting to a 3rd party app was a pain in the ass, especially with obj butchering your meshes. 

    The fact that it still only works with obj files, just shows how old and unloved it is by its creator. What is so must have about UvLayout that other apps can't do?

    As for your baking issue, more than likely the pivots for the high and low poly aren't in the right alignment, which is why resetting xform probably fixes the issue, but that is like using a nuke as a fly swatter. Still your high poly meshes should be able to withstand a reset xform without going haywire.

    Since it is probably the pivots, you should try turning on affect pivot only (in the hirearcy tab) then snap the high poly pivot to the low poly or vice versa. 
    I havn't made a single uv inside 3ds max for years because there was too much manual cutting involved in the past (don't know if it improved, have to check) but i find Headus Uv very fast. Before exporting to Headus, i assign my smoothing groups, export and with few clicks, my mesh is unwrapped automatically according to the smoothing groups. 
  • Mark Dygert
    Yep max has  had "explode by smoothing groups" for a few releases now, since 2012 I think.

    It also has explode by material and explode by edge angle. It also has a custom mode that mostly works off of angle but has a lot of settings to define the angle and how it packs the UV's. 


    The relax until flat and straighten selection, that someone mentioned, has been in since at least 2014 probably earlier.


    I find those operations to be right on par with UVLayout, but slightly faster given that I don't have to export the mesh to another app and re-import it back.
  • MartinCZ
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    MartinCZ vertex
    Yep max has  had "explode by smoothing groups" for a few releases now, since 2012 I think.

    It also has explode by material and explode by edge angle. It also has a custom mode that mostly works off of angle but has a lot of settings to define the angle and how it packs the UV's. 


    The relax until flat and straighten selection, that someone mentioned, has been in since at least 2014 probably earlier.


    I find those operations to be right on par with UVLayout, but slightly faster given that I don't have to export the mesh to another app and re-import it back.
    Thank you! going to try it right away :D
  • Farfarer
    I have no idea what software you're using that makes OBJ bake faster than FBX - there should be no difference in the bake speed (once the geometry is loaded). If there is, that suggests to me that the OBJ file actually contains less data.

    Perhaps you've got very small scales and the OBJ has had it's precision truncated (I think it defaults to 6 decimal places and maxes out at 14? you probably want to set it to the highest value), resulting in various edges being collapsed down to a single point (which looks plausible given your
  • walter
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    walter polycounter lvl 15
    In my experience, exported from ZBrush, baking with Substance:

    OBJ, option triangulated (fastest baking), in my opinion this is the best option.
    FBX, lighter from OBJ, but endless to read.
    FBX ascii, more disk space than OBJ, but regular time loading.

  • sprunghunt
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    sprunghunt polycounter
    Farfarer said:
    I have no idea what software you're using that makes OBJ bake faster than FBX - there should be no difference in the bake speed (once the geometry is loaded). If there is, that suggests to me that the OBJ file actually contains less data.

    OBJ files do contain less data. OBJ just doesn't support as many different types of object or object information as FBX. You can't export animation, cameras, or lights with OBJ but FBX supports this.  
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