int PrevBit(unsigned int bit)
The PrevBit
method returns the previous set bit before the specified
bit position, i.e. the set bit with the highest index less than the
argument. If there are no such set bits, this method returns the
value -1. If the specified value of bit is greater than or equal
to OEBitVector::GetSize()
, this method returns the same values as
OEBitVector::LastBit()
.