Obtain Animation Interpolation Mode

[l-spiro]

Hello.

I noticed that Maya can use several methods for interpolation in animations and I was wondering how to get which type is used on which tracks so that my engine can replicate more animations correctly. This is for my exporter.
For non-linear interpolation types I would also want to know how to get the tangent vectors I would need to replicate them.

Thank you,
L. Spiro

[gmask]

I think in most case you'd just bake the channels into keyframes so that this is not an issue

[joojaa]

QUOTE(L. Spiro @ 01/23/09, 08:06 AM) [snapback]299457[/snapback]
I noticed that Maya can use several methods for interpolation in animations and I was wondering how to get which type is used on which tracks so that my engine can replicate more animations correctly.

Are you talking of just anim curves? As in actuality maya does have a infinite number of interpolation types. So you can not really know how to implement it unless you implement the whole maya nodal solver.

Which is why you'd usually rely on samples because requiring key framed animation is like saying, well you know what dont use maya.

But yes for key frames you can look in the api manual and it will tell you how teh curves work. But theres a nasty surprise rotations can also work in different ways even with curves. This can also be asked but you would be using mel to do so If you think thats somehow unelegant then Read the thread Bateman has made sticky.

[l-spiro]

I already read his sticky, and I know about IK joint animations, and I did not plan to solve them.
But to save space I wanted to export as few keyframes as possible. So when a simple linear interpolation is used I export the keyframes normally as they but when IK is used I would per frame and interpolate just between those.

But in both cases I would still need to know whether to use linear/spheric quadratic for rotations and linear/hermite for vectors.

Or if I sample every frame as a keyframe and do linear interpolation, is it basically smooth enough that there is no difference at all?

L. Spiro

[joojaa]

QUOTE(L. Spiro @ 01/23/09, 12:43 PM) [snapback]299476[/snapback]
Or if I sample every frame as a keyframe and do linear interpolation, is it basically smooth enough that there is no difference at all?

Yes atleast as smooth as the maya operator sees. Be sure t interpolate the rotations by not using eulers. This is teh best you can do in any sane timeframe without neglecting all the ings you cant approach with this strategy

But how the anim curves work is described in teh api manual, their EXACT interpolation is there (so you can implement that but it takes you nowhere, and no theya re never linear its just a special case of the same spline). But thing is theres a lot more things than just IK that desnt get out this way. For example you would be loosing out n 99% of everything we use in maya. No expressions no sdk's no connections no path anim.

All of theese are very common in maya rigs in fact if if compare mys tandard rig theres lesss controlled by keyframes than any other control. And even ik is just the tip of the iceberg.

The only sane way is to step toug time with some interwall and fit teh data somehow or pray yur interpolation doesnt alias.

QUOTE
But in both cases I would still need to know whether to use linear/spheric quadratic for rotations and linear/hermite for vectors.

Maya never actually uses any of those. It just uses the same spline everytwhere except in rotations when it interprets the data as quats or sychronized eulers or independent channel euler values.