[question/request]MotionBuilder FCurves

[Former user]

I'm using MotionBuilder to generate an animation. With MoBu I can control the interpolation between two animated nodes (image attached, it's called FCurves in MoBu, I suppose it's some kind of bezier control point).

When using AssimpNET to import to convert to my custom format, accessing the NodeAnimationChannels only provides 3 translation keys without the interpolation information.

Is it possible to access that interpolation information some way so that I can recover the correct position for the intermediate frames?

Thanks!

[Nicholas Woodfield]

There is no other data coming from native assimp, so what you see is what you get. (NodeAnimationChannel is the equivalent to aiNodeAnim). Normally these keyframes are lerp/slerp’ed for the intermediate transformations.

[Former user]

Thanks for the answer (sorry for not being logged in when doing it).

Meanwhile I’ll try baking all the keys into the FBX from MotionBuilder once the animation is finished, this way the error interpolating will be minimal, and hope for support in future Assimp versions :)

JFTR I think FbxAnimCurve is the FBX SDK struct which holds the curve information, at first I didn’t know what I was exactly searching for nor how to name it.

[Nicholas Woodfield]

You should open an issue on the native assimp github and champion this feature, if you haven’t already.

I don’t know how common of a feature this is for other model formats, but it is possible the data is exposed (probably unlikely) or can be exposed via the Scene’s metadata. Scene metadata was added for the 5.x release though, so it isn’t in the current version of Assimpnet which targets 4.1