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3DS Max, normal map problem

I make my normal maps using 3D studio max 8's Render to Texture function.

So far the normals maps come out good. Any anomalies I fix up in Photoshop. So far everything's been ok. I've been steadily cranking out my work with no problem.

Suddenly I ended up with this problem:
http://home.comcast.net/~acknar/problem_1.jpg
This is in the viewport.
Notice the box-like anomaly on the lower right side of the abdomen.

I've inspected the normal map, I checked all channels, no problem what so ever.

The rest of the model is fine.

Both the Hi-Res mesh and the Low poly meshes are single meshes (no floating geometry). Both have had their transforms reset although I'm going to go back and do it again just in case.

The Hi-Res mesh doesn't have UV coordinates or anything like that. I've never found the need for the Hi res mesh to have UV coordinates.

The low res mesh has UV coordinates. The low res mesh was a mirror of the right side. But in the UV I moved the left side of the UV map to the next tile over.
http://home.comcast.net/~acknar/problem_2.jpg

I've done this with all my models and have never had any issues. Back when I learned how to do normal maps, I was told that to avoid any issues, if some part of the model was mirrored, I should grab the mirrored part and place it on the next UV tile.

This is what it looks like rendered, notice there are no problems:
http://home.comcast.net/~acknar/problem_3.jpg
That's using Max's default scanline renderer. Using the mental ray renderer yields the same results. I.e. no problems at all.

Here are the options I use when generating the Normal Map:
http://home.comcast.net/~acknar/problem_4.jpg

Anyone know what's going on? What am I doing wrong?

Although it renders fine using the renders in 3Ds max, the anomaly shows up in the viewport only. I'm afraid that if I use such a model in a game engine the problem might show up in there.

Another issue I just discovered; I used a different Normal Map, and turns out the strange anomally is still there! Eventhough the normal map looks fine on it's original model, when I put it on this model that anomaly shows up.

hrm. Anyone know what's up?

Replies

  • cman2k
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    cman2k polycounter lvl 17
    the evidence points towards a problem with the model itself. I'd double check all your verts are welded, reset xforms, etc.
  • helldiver
    Seems like something to do with the smoothing.

    The anomaly doesn't lay on any edges or polygons, I checked all this and the geometry is solid.

    It's a 1202 solid mesh. Smoothing is Auto and Prevent Indirect Smoothing checked and set to 180 like all of my models, since I don't use smoothing groups for these models.
  • System
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    System admin
    Have you tried putting the viewport camera inside the mesh so your looking from inside out or moving verts/edges near the problem area?

    Also try an STL check modifier with individual checking then reset x form and collapse the stack to edit poly, if this still doesn't work then reset max and merge the scene.

    If again no luck then you could have some faulty geometry so just delete the poly's in the affected area and re-unwrap that bit.

    ps: 2 things: why did you triangulate the mesh? A game engine will do this anyway when you port it so there's no need. Why are you using no supersampling when your baking? Result would be much better if you use mental ray to bake at high settings. Here's a preset for that :)
  • sprunghunt
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    sprunghunt polycounter
    looks like a problem with the UV's to me
  • helldiver
    To GCMP, thanks, working on it now. I triangulate my in-game mesh only. It's a habit of mine, it also lets me keep tabs on how many polys an area has, if I have to edit it, if it crunches incorrectly when animated, and a whole slew of other reasons. The hi-res mesh and the base mesh for the hi-poly one isn't triangulated however. Thanks for the preset, I hadn't thought about using Mental Ray as the baker until recently.

    To Sprunghunt: Anyway you can point out what you see wrong? I can post a larger image. I'm using the same process I've always used :(
  • helldiver
    http://home.comcast.net/~acknar/problem_5.jpg

    This is after removing that entire side of the torso and rebuilding it from scratch. Now as you can see there is a small anomaly on the left side, I'll fix it here in a moment.

    Why did this happen? I'm lost now. I've never had an issue like this before, although I do recall a small anomaly one time on a character's nose.

    Update:

    Below is the final result after fixing the left side, I rebuilt those polygons as well. Now I'm having an issue with a UV seam that if I weld it, I end up with an anomaly on the right side. It isn't even down the center :(

    See below
    http://home.comcast.net/~acknar/problem_6.jpg

    The left most shows the Torso as it is now. On the right you notice the UV layout and I put a red arrow to show the seem on the UV. If I weld it, I end up with that anomaly you see on the picture with the red border :(

    I can leave it like it is, but having seem lines in my UV pelt bugs me big time.

    Any help or tips?
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