| curve | The curve to modify. |
| index | Keyframe index. |
| tangentMode | Tangent mode. |
Change the specified keyframe tangent mode.
The keyframe tangent mode will be used by the Curve Editor to generate tangents automatically. Changing the tangent mode here will also recalculate Keyframe.inTangent and Keyframe.outTangent.
Additional resources: AnimationUtility.SetKeyLeftTangentMode, AnimationUtility.SetKeyBroken.