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Maya Artifacts in normal maps.

For the past few days I've been trying to render a decent normal map in Maya 2009, but I keep getting weird artifacts, see picture:
strangeNormals.jpg
(Screen shots of High and Low poly in Maya, screengrab of the models in the realtime tool we use at work)

I don't know what's going wrong, the same models render fine in eiter Max or xNormal, but I used to be able to render decent maps out of Maya. If I open the normal map tga into photoshop, and edit the levels of the red and green channel, I can see the artifacts.
testFlPlaneoyd2sampledNormals_colorChanged.tga

I've tried a lot of different settings, and as far as I know they are the same that anyone uses who is trying to render Normal Maps in Maya. Also tried different file formats, but no luck.

Replies

  • EarthQuake
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    The first image is simply a matter of filtering, i'm not sure what sort of filtering maya uses by default in HQ mode but it seems to be different than other apps, so if you've got a pretty low res image you're going to see issues like that. Using a HLSL shader or viewing in a game engine that should go away.

    The 2nd may also be a matter of resolution, one simple test you could do is render a much larger texture and see if that fixes your issues, as you have a lot of long, thin triangles that are really hard to represent unless you have a good deal of resolution. You see you do not have enough pixels to accurate account for the smoothing gradiations on the low, so you get those sort of artifacts. Using some hard edges would likely help your problem as well(as there will be less gradiation to account for).

    Now, as far as "seeing artifacts" in photoshop, what you're seeing is most definitely not "artifacts" but the proper values in the texture to compensate for the mesh normals of your low poly.
  • myHighness
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    Oh, sorry, I was in a hurry last night, the red objects aren't in Maya, but it's in Quest 3D.

    Made a comparision shot:
    compareNormals.jpg
    The model is made in Maya, and exported with Collada to Max and xNormal, never had problems with that before, and there doesn't seem to go anything wrong at that point.

    I've tried a 4096*4096 map, but still had the same problem.
    Talked with some other people about this, and some say it might be a problem with how Quest is displaying the vertice normals.

    Only thing that might cause a problem (but I doubt it), is that the vertices aren't on the same height, although I scaled them, snapped them, let my collegue who works in 3dsMax try it etc. So I guess they're on the right level.

    I'm a bit lost, as I've never had this problem before.
    I also made a .zip of the three normal maps used in that comparision shot, click.

    Thanks for your reply though.
  • EarthQuake
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    maya, max and XN generally all render a little differently, so if you get correct results from max, it makes sense that you wouldn't get them in maya.

    you may want to look at this thread for some more info on why different apps bake things differently, and how important it is to use the app that gives you the tangent data your engine expects(in this case it looks like max)

    http://boards.polycount.net/showthread.php?t=68173
  • MM
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    MM polycounter lvl 18
    also, triangulating the low poly before baking might help a little.
  • SpeCter
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    SpeCter polycounter lvl 14
    And your normal map points towards the wrong direction in quest3d with your xnormal settings
  • bugo
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    bugo polycounter lvl 17
    if for some reason you exported from max to maya, try unlocking the normals before baking in maya.
  • myHighness
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    EarthQuake wrote: »
    you may want to look at this thread for some more info on why different apps bake things differently, and how important it is to use the app that gives you the tangent data your engine expects(in this case it looks like max)

    http://boards.polycount.net/showthread.php?t=68173
    Already read that thread before, am reading it again in case I've missed something first time.

    @MM: Tried triangulating, no difference.

    @bugo: only exported from maya to max, and tried the unlocking anyway, no luck there.

    Decided to just bake in Max, it's gonna take too much time otherwise. Still don't know why I don't get correct bakes in Maya, High Quality viewport displays it the same as Quest3D.
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