HOW TO Turn off the auto tangent checkbox on keyframes using python API

heytraile

Hi, I'd like to know how to turn off the Auto Tangents and Remove Overshooting checkbox on keys in C4D using the python API. I wrote a tool to bring keyframe data from C4D to other applications but with Auto Tangents and Remove Overshooting on, I'm getting differences in my tangents. Once I turn them off and run my tool again, I'm getting the correct results.

There is the

CKey.SetAutomaticTangentMode

but it does nothing for me. Is there a way to do this with the API? I've attached an image to show the checkboxes I'm referring to.

Thanks in advance.

kng_ito

Hi,
These can be used for doing so.

CKey.ChangeNBit(c4d.NBIT_CKEY_AUTO, False)
CKey.ChangeNBit(c4d.NBIT_CKEY_REMOVEOVERSHOOT, False)

By the way, if you want to get correct value of tangents, CCurve.GetTangents() should work correctly, instead of using CKey.GetTimeLeft, etc.

i_mazlov

Hi @heytraile ,

Welcome to the Maxon developers forum and its community, it is great to have you with us!

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About your First Question

Function c4d.SetAutomaticTangentMode() is meant to change the value of the "Angle" attribute and in my opinion is just poorly named.

What you actually need to do is to execute function ChangeNBit() (@kng_ito, thank you for providing fast answer). However, the usage kng_ito showed above is not 100% correct. Namely, you'd need to use one of the NBITCONTROL values. In case you want to remove these checkboxes, the code would be:

key.ChangeNBit(c4d.NBIT_CKEY_AUTO, c4d.NBITCONTROL_CLEAR)
key.ChangeNBit(c4d.NBIT_CKEY_REMOVEOVERSHOOT, c4d.NBITCONTROL_CLEAR)

You can also find some code examples on how to work with animation related data in our repository, e.g. CTrack Create Keys

Cheers,
Ilia

heytraile

@i_mazlov Thanks much for explanation.