Field Name	Field Type	Field Constraints	Field Notes
progress	float	<div style="padding-left: 0px;">Minimum = 0<br>Maximum = 1</div>	Normalized progress of this frame along the spline, from 0.0 (start) to 1.0 (end).
time	float	<div style="padding-left: 0px;">Minimum = 0</div>	Time (in seconds) at which this progress should be applied.
easing	enum easing_function		Optional easing function used to interpolate towards this progress key frame. Defaults to "linear" if omitted.