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adjusting quaternion tangents?

Olli.
polycounter lvl 8
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Olli. polycounter lvl 8
ok i know quaternion doesnt really have tangents, but is there a way to fine tune the trajectories? i know i can click the trajectories button to SEE the trajectories but it doesnt give me any more control over the actual movement between keyframes.
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  • Warheart
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    Warheart polycounter lvl 18
    TCB settings? (assuming you're in Max)
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  • Mark Dygert
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    Mark Dygert mod
    Yep, in the curve editor right click a key to bring up the Tension, Continuity and Bias settings from there you can adjust the values and see their effect on the curves. If you're working in biped they realize that Euler curves with handles are still easier to work with so they allow biped to be switched to Euler mode (max2011 and up).

    If you must work in TCB you might want to check out some helpful scripts that give you quick one button access to common presets, specifically "Biped Keyer" but the other scripts might be useful too.
    http://www.polycount.com/forum/showthread.php?p=1117300#post1117300
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  • Olli.
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    Olli. polycounter lvl 8
    yeah im using bipeds but i heard i might get gimbal lock on my anims with euler.. I'll check out them scripts.
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  • Mark Dygert
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    Mark Dygert mod
    Gimble lock might happen but only in rare cases when two axes align perfectly. So to get around it you rotate one of them a fraction less so they don't align mathematically perfectly. So instead of 360 you do 359.999 degrees and gimble lock is gone. That's if you even encounter it at all, which is really rare. I've hit it once in the 4 years I've been animating and that was with a custom rig I created for a spinning globe object.

    It's easier to solve than forcing yourself to work with TCB values at least for me and I'm fairly comfortable with TCB.

    I think I remember reading that Biped even set to Euler curves is still using TCB/Quaternion under the hood just the interface is different. So you can't actually gimbal lock a biped, but I can't seem to find anything to back that up at the moment so maybe I'm wrong and it does work in both systems...
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  • Olli.
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    Olli. polycounter lvl 8
    i've done a lot of non-biped rig animation, and i've found that even if the axes dont lock perfectly, sometimes the rotation path may be compromised and the object does a weird flip where it shouldnt during a simple rotating animation.
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