Method Intersect

libraries/lib-builtin-effects/TruncSilenceBase.cpp:741–870

Finds the intersection of the ordered region lists, stores in dest

// Finds the intersection of the ordered region lists, stores in dest
void TruncSilenceBase::Intersect(RegionList& dest, const RegionList& src)
{
   RegionList::iterator destIter;
   destIter = dest.begin();
   // Any time we reach the end of the dest list we're finished
   if (destIter == dest.end())
      return;
   RegionList::iterator curDest = destIter;

   // Operation: find non-silent regions in src, remove them from dest.
   double nsStart = curDest->start;
   double nsEnd;
   bool lastRun = false; // must run the loop one extra time

   RegionList::const_iterator srcIter = src.begin();

   // This logic, causing the loop to run once after end of src, must occur
   // each time srcIter is updated
   if (srcIter == src.end())
   {
      lastRun = true;
   }

   while (srcIter != src.end() || lastRun)
   {
      // Don't use curSrc unless lastRun is false!
      RegionList::const_iterator curSrc;

      if (lastRun)
      {
         // The last non-silent region extends as far as possible
         nsEnd = std::numeric_limits<double>::max();
      }
      else
      {
         curSrc = srcIter;
         nsEnd = curSrc->start;
      }

      if (nsEnd > nsStart)
      {
         // Increment through dest until we have a region that could be affected
         while (curDest->end <= nsStart)
         {
            ++destIter;
            if (destIter == dest.end())
            {
               return;
            }
            curDest = destIter;
         }

         // Check for splitting dest region in two
         if (nsStart > curDest->start && nsEnd < curDest->end)
         {
            // The second region
            Region r(nsEnd, curDest->end);