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FBX animation problem

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I'm writing a converter to take some FBX animations exported from Max. The converter is to translate the FBX's into a proprietary format since the final application will not use the Autodesk FBX SDK. To achieve this I am trying to understand exactly how the take nodes and curve nodes work. This is ok, except that if a take node ( KFbxTakeNode ) has a curve node ( KFCurveNode ) but this curve node has NO keys, then how is the global transform of the node calculated ? ( ie. how does the method KFbxNode::GetGlobalFromCurrentTake calculate the transform ? ) I can't find an answer to this in the SDK, and all the examples use the method without explaining how the result is arrived at.... Are there any experts on FBX animation out there ?....

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personally, I just sample data from FBX rather than dealing with the curves directly, then it's just a case of doing....

fbxTakeNode->GetEulerRotationX()->Evaluate(curr_time)


and then converting to quat or whatever you are planning. With FBX the computation goes something like this for a local space matrix,


[S] * [Pre] * [Rot] * [Post] * [T]

where
S=scale
T=translate
Pre=KFbxNode::GetPreRotation( KFbxNode::eSOURCE_SET )
Post=KFbxNode::GetPostRotation( KFbxNode::eSOURCE_SET )
Rot=current fbxTakeNode->GetEulerRotation#()


It basically uses the same matrix construction as Maya, i'd check out the docs to MFnTransform and MFnIkJoint in the maya API docs for more info (if you have it available).

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