The Swap Events button switches the position of two selected events in the queue.
This is useful if you have images in the wrong order for compositing. The background image has to be first and the foreground image with the alpha channel has to be second.
To switch the positions of two events in the queue:
(Swap).
Swap Events might not be allowed if the result would be impossible to execute.
In this sample queue, the two top level events, Front and Fade, could be swapped. You can almost always swap events at the top level.
However, at lower levels, where events start getting nested, the output of a lower level event must be valid input to its parent event. In the sample queue, the output of the Loop Once event would not be recognized by the Fade event, so the Swap Events button remains inactive and you cannot swap them.
