.presets has been around longer than .eani, so that’s probably why Animal Logic used .preset files. To look at the the difference between .preset and .eani, you’ll need to pay attention to the minutae of the docs wording, plus consult the next page about .eani files and compare the two. To look at it from another perspective, .preset files are simply property set data recorded to a binary file. In the case of action sources, the .preset includes animation data if it’s FCurve data. The .preset file is essentially a mechanism to transport the animation data between models and/or scenes. Once imported, the data is always local to the scene. In constrast, .eani files are the equivalent of referenced models for action sources. They can be used over and over again across many scenes, and across many models in those scenes which the parameters in the action source can be remapped. The animation data is not considered part of the scene and therefore not saved with the scene file (.scn), but is still recorded as an entry in the .scntoc. This also enables lazy loading which can be handy on large scenes or systems where memory has limitations. Only data for the active frame range is loaded and when it is needed. Once loaded, it stays loaded until you close the scene. Downside is seek time may increase depending on variables such as scene complexity, hardware performance, amount of data in the .eani file, etc... If you need the ability to modify the animation data from outside of Softimage, then you’ll need to use .xsi files instead of .eani files as only .xsi files are compatible with the FTK and Crosswalk SDK.
How’s that? Matt
