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Need help testing my model preprocessor.

PostPosted: Tue Jul 16, 2013 11:26 pm
by stoopdapoop
A little background, if you're interested
So over the past few nights I've been working on a model preprocessor that takes .FBX models as inputs, and outputs my own model format.

The FBX format is really big, abstract format that has support for everything under the sun, and a several different ways to describe geometry. For this reason, modeling tools have some flexibility when exporting models, and I want to be sure that my preprocessor can handle .fbx files from different modeling packages.

Unfortunately, none of these representations are good for real time rendering. They're great for editing and storing tons of information. The FBX format is not meant to be a "destination" format, but instead an "interchange" format. that you'll usually want to convert into your application's native format before using.

I'm trying to save some work by only interpreting geometry the way that the popular modeling programs actually output it, opposed to implementing all the ways the format supports.

In particular I want to make sure that I'm reading hard edges/smoothing groups correctly

What I need from you guys
I need you guys to send me some .fbx models from different programs. I won't be using them for anything other than testing the tool. They don't have to be fancy or anything, but they should have some of the qualities I describe in the next section.

What I'm looking for in a model
  • The model must have been made entirely within your modeling package. if modeled in Max, it needs to be exported in Max, if modeled in Maya, it needs to be exported in Maya. If you create the model in Max, then send it to Maya and export it as .fbx then that won't help me.
  • Every mesh in the scene needs to have exactly one UV map, it doesn't have to be a sensible one, but it needs to be there. Even something like a planar projection over the entire mesh will work, it just has to be something.
  • Extra scene elements are fine, if you have lights, cameras, animations, embedded textures, whatever, it shouldn't affect my import process.
  • When you export your .fbx, look for an option about exporting "tangents" or "bitangents" or "binormals" if you see something like this, then make sure to set it to true. if you find an option like this, make sure to tell me. If you don't see anything like that then don't worry about it, my processor will calculate them automatically, but it's better to get them from the package.
  • Preferably, models should have a mix of hard and soft edges (or should have multiple smoothing groups if working in Max) This is not a strict requirement though.
  • Multiple meshes are fine, but they need to all follow the rules.

What packages I need (duplicates are fine)
  • Any version of Maya
  • Any version of Max ---Thanks Jimonions---
  • Any version of Blender
  • Any version of C4D ---Thanks Kraid---
  • older version of Softimage ---Thanks Epifire---
  • Any Version of anything else I might have forgotten. :)

Any help is appreciated :]

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 8:19 am
by jimonions
done in 3ds max 2013 x64 and exported with tangents and binormals
has one uv map and multiple hard and soft edges with different smoothing groups.
badurl.com reuploaded below

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 9:07 am
by stoopdapoop
Thanks jimonions, but it says the file was blocked because of a violation of terms of service.

Maybe the filename tripped it up?

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 9:29 am
by Epifire
Softimage 2012 supports FBX, want one from it too?

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 10:02 am
by stoopdapoop
Actually, yeah, that'd be cool.

The reason I didn't put softimage on the list is because I use it myself, so I have ready access to it.

But I use 2013, and according to the autodesk interoperability charts, there's a bit of a difference between the 2012 and 2013 fbx exporters, so I guess I should test against 2012.

http://images.autodesk.com/adsk/files/a ... _chart.pdf
http://images.autodesk.com/adsk/files/s ... 12_map.pdf

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 10:14 am
by Black_Stormy
Here's one from blender 2.66a - the exporter that ships with the program - it's just an arbitrary shape.

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 10:21 am
by kraid
Wanna have a real task, try this:
http://www.mediafire.com/download/7j7u2epop3cmels/fusebox.fbx

Made with Cinema 4D R14, exported to fbx v7.2 (2012) saved normals.
Model uses Phong breaks (comparable to XSI's hard eges)
Model is triangulated and has a normal-tag applied (to fixate the normals for export)

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 10:31 am
by jimonions
that's weird, I was able to download it after uploading.
I re uploaded it again under a different name.
http://www.mediafire.com/download/fb39o ... lysafe.rar

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 10:46 am
by stoopdapoop
Image

Image

I think it's right, I'm assuming that the lip of the box cover is where the hard edges are, and everything else is using regular normals, right?

The texture is just some cool looking cockatiel I found.

And stormy, I'm not reading any UV's does your model lack them, or am I just not detecting them?

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 11:02 am
by stoopdapoop
Image

Perfect, thanks Jimonions. Looks things are mostly working so far.

The model's orientation is wrong (he's lying face down) but that's something I can fix myself.

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 1:48 pm
by srredfire
#poopengine

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 6:37 pm
by Epifire
I haven't tried going up to date with things so I'm actually downloading Softimage 2014 as well. I don't think with 14' there would be a huge difference but I will have that and 12' to give comparisons from.

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 6:57 pm
by kraid
Right. The box has hard normals on allmost every edge while the cables are smoothed.
One thing i noticed is that the model looks mirrored in your app.
Her'e's what it looks like in Cinema 4D.
Image

Re: Need help testing my model preprocessor.

PostPosted: Wed Jul 17, 2013 8:01 pm
by Black_Stormy
Well I didn't unwrap my model or assign any materials, but I was under the assumption that blender immediately created normal data when working with meshes. There's no nurbs or anything funky in the scene, just a mesh, a camera and a lamp.

Also with models facing the wrong way, blender allows you to assign any axis as the forward axis so I assume that as you get different models from different packages they'll probably all have different forward axes.

Re: Need help testing my model preprocessor.

PostPosted: Thu Jul 18, 2013 4:05 am
by stoopdapoop
Yes, packages usually create their own normals, and if they don't then they give you enough information stored in "edges" or "polygons" to allow you to generate the vertex normals yourself.

Your model had normals though, it was the UV's that were missing. I don't want to generate a set of test UV's in code because I'm testing the importer and want to make sure everything works as expected.

And yeah, I knew that the forward axis thing was going to come up eventually. One of the nice things about the .fbx format is that exporters have to store their axes and handedness in the file somewhere, so you can just remap them on import if they don't match your destination format. I just haven't gotten around to doing that yet.