The animation curve (see property Curve) contains several curve keys (also known as 'key frames') that define the change of the value. The curve parameter is the animation time. A curve key defines the current value at a certain point in time. It also defines the type of interpolation that is used for the segment between the current and the next curve key. All relevant types of spline-based interpolations can be used for the curve segments.

Duration: An animation curve, by default, runs from the start (curve parameter = 0) until the last curve key is reached. The parameter of the last curve key determines the natural duration of the animation. The optional properties StartParameter and EndParameter can be used to explicitly define which part of the animation curve should be played.

Loop Behavior: When the StartParameter is less than the parameter of the first curve key or EndParameter is greater than the parameter of the last curve key then the curve is automatically repeated using a certain loop behavior. The loop behavior can be defined using the properties PreLoop and PostLoop of the Curve.

Important: The animation curve requires that the curve keys are sorted ascending by their parameter (time value). The method Sort can be called to sort all curve keys.

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