I'll preface this by stating that I'm a developer and not a 3D artist, and am still getting my feet wet with 3D modeling, Blender, etc. I have written some software that generates textured mesh models (OBJ/MTL files) for me, and I can then import them into Blender and view them.

One such model can be found here - if you're interested!.

The problem is, in each case, when I import the OBJ file into Blender, there's always two issues that require manual correcting:

  1. The model is extremely tiny and I need to zoom way in on it; and
  2. The model is never rotated/oriented right-side up, and I always need to play around with it so that I can have it oriented correctly (and by "correctly", I mean right-side up and front-facing)

For example, let's take the model I linked to just above. When I first import it into Blender, this is what I see:

enter image description here

But after zooming in on it and rotating it manually, it becomes:

enter image description here

So my theory (but please correct me if I'm wrong!!!) is that my software is either not configured right, or has a bug in it, and is not storing "orientation parameters" (scale, rotation, etc.) in the OBJ file (or any of its constituent files) correctly. And, because these parameters are incorrect, when Blender goes to import the model, it displays the model correctly - according to the incorrect parameters!

So, my question:

Is this theory plausible, and how could I tell? I'm not familiar with OBJ models/files, but perhaps there's a way to inspect their contents (in Blender or from some OBJ data reader/tool) and see what these 'orientation parameters' are incorrectly set to?

Perhaps I can import a model into Blender and see what its default 'orientation parameters' are, then manually correct them, view what its new 'orientation parameters' are, and then use their difference to figure out what needs to change in my software?

The desired end result would be able to run my software, generate a model (OBJ + MTL files, etc.), import them into Blender and have them displayed correctly (again, right-side up and front-facing) without the need for manual correction. And if my theory is correct then I need to tweak something in my software to write accurate 'orientation parameters' to one of these files. I'm just not sure which file nor which parameters. Can anyone help steer me in the right direction here?

  • $\begingroup$ Please use BSE's image adding tool. My browser can't establish a secure connection with the other site that you are using, so I can't see them at all. $\endgroup$ – JakeD Nov 17 '16 at 15:11
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    $\begingroup$ It looks like your software is not storing the orientation parameters, what method does it use to align the mesh to coordinates? $\endgroup$ – Denis Nov 17 '16 at 15:14
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    $\begingroup$ What do you have "Clamp Size" set to for the .obj importer? $\endgroup$ – JakeD Nov 17 '16 at 15:14
  • $\begingroup$ Thanks @pycoder (+1) - I'll try to get you those images in the next 30 mins or so. Per your Clamp Size comment, I'm looking at Blender's UI right now, trying to figure out where I can find it! According to this answer I should be able to see Clamp Size inside a menu called Import OBJ, but I've searched high and low, and don't see that anywhere. Any ideas as to how I can find it? $\endgroup$ – smeeb Nov 17 '16 at 15:23
  • $\begingroup$ Thanks @Denis (+1) - when you ask what method I'm using to align mesh to coordinates, can you elaborate what you mean by method? You mean which algorithm I'm using, or just an explanation of the process I'm using, or something else? Another way to put it: in your mind, what are the typical methods that are used for this sort of thing? Thanks again! $\endgroup$ – smeeb Nov 17 '16 at 15:40

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