Accesses the values on the previous frame of the attribute specified by the reference string. The fact that the accessed data is evaluated on the previous frame is the main difference with the Get Data node.
Such a node is especially useful to interpolate values in order to approximate values for any fraction of the current frame, in order to minimize frame rounding artifacts.
Like the Get Data node, you can build the path to the data you want to fetch by daisy chaining Get Data nodes.
To use both Get Data at Previous Frame and Set Data with an object, whether it's the self or another one, in the same ICE tree, the object must have a Simulation region in its construction stack. This applies even if you are getting and setting different attributes. Having a Simulation region in the stack means that the lower regions of the stack will be evaluated only on the first frame of the simulation, and subsequent frames will be based on the previous frame — see ICE Trees and the Construction Stack for more information.
For more information about Get Data at Previous Frame, see Getting Data on Scene Groups [ICE Fundamentals].
