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XNormal - Normal Map Comes Out Blank

Aaren_Gibson
Aaren_Gibson
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Aaren_Gibson null
Pictures of the issue: http://imgur.com/a/aCyN0

Tutorial I followed: https://www.youtube.com/watch?v=WBhbKnjwcr8

I'm new to xNormal, anyone know what I did wrong?
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  • Bek
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    Bek interpolator
    fire up that 3d viewer in xNormal and look at why it missed. Could be any number of simple things. Meshes not loaded. Meshes scaled differently. Cage not pushed out. Cage not loaded. Not enough ray distance if no cage. The viewer lets you do all sorts of basic troubleshooting. If nothing there looks wrong, try exporting as a different file format, maybe UV's didn't get exported correctly or something.
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  • Aaren_Gibson
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    Aaren_Gibson null
    Exported as .obj, then re-imported to Cinema, and the UV's are still there

    In the 3D viewer, both the high poly and the low poly show up fine, overlapped over each other: http://imgur.com/a/hik3i

    I don't have a cage and I used the ray distance calculator under tools. After using the calculator, I pressed "Copy results", do I have to paste that somewhere or does it set it automatically?
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  • Bek
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    Bek interpolator
    It does it automatically. You can see the values updated under the low-poly item. Perhaps try fbx or some other file format. Otherwise try disabling 'discard backface hits' under baking options and see if anything shows up.
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  • Aaren_Gibson
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    Aaren_Gibson null
    'discard backface hits' didn't make a difference

    However, it looks like exporting as .FBX did the trick, but it came out a little messed up:     http://imgur.com/a/H9DUi


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  • Aaren_Gibson
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    Aaren_Gibson null
    Does it matter if a model is open or closed geometry?
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  • Bek
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    Bek interpolator
    No, but I think the problem is partial UV's — which OBJ does not support, which might explain why you get no results with OBJ but some broken parts with FBX.

    So, does every (and I mean absolutely every) polygon have a corresponding UV piece? If there's no simple way to check in cinema4d (I imagine you can just ctrl+A in the uv window, and then look in your 3d view for any polygons not selected) but if not, just export a small section of the model you know is good and try again. Or apply a checkered grid to the model using those UV's and observe for any oddities. The obviously broken UV's on the FBX bake seem to support this idea (missing parts, plus stretched faces where the program has tried to stitch together geometry between two different islands, like after deleting an edge that was also a UV seam).
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  • Aaren_Gibson
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    Aaren_Gibson null
    Nope, all polygon's have been mapped
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  • Bek
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    Bek interpolator
    Do you have another program that can open the file to check its UV's once exported? Because all the evidence points towards UV's breaking after export. Or at least check the .FBX version you exported that did bake something out, and seeing if its UV's remain intact. The other option is you have multiple UV sets and the .obj baked to the blank set, and the FBX didn't or something like that. But something is definitely broken with the UV's.

    if you really want, upload the .obj and .fbx to dropbox and I'll have a quick look at it.
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  • Aaren_Gibson
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    Aaren_Gibson null
    High Poly: (Link Removed)
    Low Poly: (Link Removed)
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  • Bek
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    Bek interpolator
    The tip triangle on the underside of the boot is missing or infinitely small (in the UV's). Not sure if thats causing your issues but worth fixing anyway.

    Some general comments on good uv'ing too:

    1) Overlapping pieces - you should offset one of the pieces that are mirrored/overlapped (arms) so only one exists in the 0,0 to 1,1 UV space for baking, otherwise you'll run into problems. Check the wiki for more info. You should also move the top parts of the boots that shares UV space with them by +1 (So it will still use the general texture, which I assume is what you planned, but won't be taken into account by the baker). Additionally mirrored pieces require the same triangulation, and you should triangulate everything before baking.
    2) Some pieces aren't stitched, which is also bad (end of the belt, part of the boots). The boots also have self-overlapping faces.
    3) You should relax the islands to minimise distortion, atm the have a somewhat uneven texel density
    4) Ideally you will straighten as much as possible to avoid aliasing (not much when talking of characters) here the belt makes a good example though.
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  • Aaren_Gibson
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    Aaren_Gibson null

    Alright, I'm going to restart from the low poly and try again.

    Thanks for the help and tips Bek :)

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