get Previous Span X
Returns previous X distance between pointers in pixels.
Pointers are sorted by the time they were placed on the screen until lifted up. This means that index 0 will reflect the oldest added, still active pointer and index (getPointersCount - 1) will reflect the latest added, still active pointer.
The order of parameters is irrelevant.
Return
Previous X distance between pointers in pixels.
See also
pointer Id List
Parameters
first Pointer Index
one of pointers indexes
second Pointer Index
one of pointers indexes