XNA: Skinning sample, keyframes and time

Question

I've been using the skinned sample from XNA tutorials to understand and play FBX files animation. While the animation in all my tests runs correctly, I fail to understand the technic to calculate time versus keyframes.

Most of the models I found so far for free and testing purpose on google store all animations into one "take" and split frames into all animations. So, walk would be frame 1 to 14, run 15 to 30, jump 32 to 48, etc. On the other hand, the skinning sample loads all frames and store a calculated time which it will be using to loop the animation.

The part where I'm getting confused is on the keyframe part. For example a model I've been trying to load gives me a 12 seconds timespan with 20160 keyframes. While the timespan seems right, the keyframe count seems to have been altered in some way since in Milkshape and in the Autodesk converter the frame count is at 300. What is it doing?

Here's my setup for model conversion.

1. I use Milkshape 3D to export a model and its animation to an FBX binary file.
2. Then, I use the Autodesk file converter to convert the file into an ASCII FBX (so far I tried and tested the FBX2012 and version 6.1, which is the same as the "dude.fbx" given with the skinning sample).
3. Processing model inside XNA with the SkinnedModelProcessor given with the skinning sample.

What I'm really trying to achieve here is to split animation into smaller clips so I can switch depending on the user action. I'm perfectly fine with counting keyframes, but as you can see, the keyframe count is way too high.

Answer 1

It's been a couple of days, and I'm still searching for a perfect solution. I did, however, find something to work with for now. My main problem was to work with time span instead of frame span. Also, I think the models I'm using aren't rigged correctly. So, I still can't get the "walk" animation to play right.

I'm using this method to split up the clips at the PROCESSING time: http://forums.create.msdn.com/forums/t/1415.aspx?PageIndex=2 (see Spacedude's post in the middle of the thread).

Here's what I'm doing to test this out. SplitAnimations() is called in the Process() method after it has been processed.

Dictionary<string, AnimationClip> animationClips;
animationClips = ProcessAnimations(skeleton.Animations, bones);
animationClips = SplitAnimations(animationClips["Animation"], @"C:\defs.txt");

Then, in my component, I do this to start a clip:

    protected override void LoadContent()
    {
        base.LoadContent();
        var data = Model.Tag as SkinningData;

        AnimationPlayer = new AnimationPlayer(data);

        if (!string.IsNullOrEmpty(CurrentClip) && data != null)
        {
            var clip = data.AnimationClips[CurrentClip];
            AnimationPlayer.StartClip(clip);
        }
    }

It'as all testing code for now. More to come.