/// <summary>
/// Internally append this slice (which must be allocated from our free buffer); this does the work
/// of coalescing, updating _data and other fields, etc.
/// </summary>
Slice <TTime, TValue> InternalAppend(Slice <TTime, TValue> dest)
{
// dest must be from our free buffer
HoloDebug.Assert(dest.Buffer.Data == _remainingFreeBuffer.Buffer.Data);
if (_data.Count == 0)
{
_data.Add(new TimedSlice <TTime, TValue>(InitialTime, dest));
}
else
{
TimedSlice <TTime, TValue> last = _data[_data.Count - 1];
if (last.Slice.Precedes(dest))
{
_data[_data.Count - 1] = new TimedSlice <TTime, TValue>(last.InitialTime, last.Slice.UnionWith(dest));
}
else
{
Spam.Audio.WriteLine("BufferedSliceStream.InternalAppend: last did not precede; last slice is " + last.Slice + ", last slice time " + last.InitialTime + ", dest is " + dest);
_data.Add(new TimedSlice <TTime, TValue>(last.InitialTime + last.Slice.Duration, dest));
}
}
_discreteDuration += dest.Duration;
_remainingFreeBuffer = _remainingFreeBuffer.SubsliceStartingAt(dest.Duration);
return(dest);
}
public int Compare(TimedSlice <TTime, TValue> x, TimedSlice <TTime, TValue> y)
{
if (x.InitialTime < y.InitialTime)
{
return(-1);
}
else if (x.InitialTime > y.InitialTime)
{
return(1);
}
else
{
return(0);
}
}
/// <summary>
/// Trim off any content beyond the maximum allowed to be buffered.
/// </summary>
/// <remarks>
/// Internal because wrapper streams want to delegate to this when they are themselves Trimmed.</remarks>
void Trim()
{
if (_maxBufferedDuration == 0 || _discreteDuration <= _maxBufferedDuration)
{
return;
}
while (DiscreteDuration > _maxBufferedDuration)
{
Duration <TTime> toTrim = DiscreteDuration - _maxBufferedDuration;
// get the first slice
TimedSlice <TTime, TValue> firstSlice = _data[0];
if (firstSlice.Slice.Duration <= toTrim)
{
_data.RemoveAt(0);
#if DEBUG
// check to make sure our later stream data doesn't reference this one we're about to free
foreach (TimedSlice <TTime, TValue> slice in _data)
{
HoloDebug.Assert(slice.Slice.Buffer.Data != firstSlice.Slice.Buffer.Data);
}
#endif
_allocator.Free(firstSlice.Slice.Buffer);
_discreteDuration -= firstSlice.Slice.Duration;
_initialTime += firstSlice.Slice.Duration;
}
else
{
TimedSlice <TTime, TValue> newFirstSlice = new TimedSlice <TTime, TValue>(
firstSlice.InitialTime + toTrim,
new Slice <TTime, TValue>(
firstSlice.Slice.Buffer,
firstSlice.Slice.Offset + toTrim,
firstSlice.Slice.Duration - toTrim,
SliverSize));
_data[0] = newFirstSlice;
_discreteDuration -= toTrim;
_initialTime += toTrim;
}
}
}
/// <summary>
/// Map the interval time to stream local time, and get the next slice of it.
/// </summary>
/// <param name="interval"></param>
/// <returns></returns>
public override Slice <TTime, TValue> GetNextSliceAt(Interval <TTime> interval)
{
Interval <TTime> firstMappedInterval = _intervalMapper.MapNextSubInterval(interval);
if (firstMappedInterval.IsEmpty)
{
return(Slice <TTime, TValue> .Empty);
}
HoloDebug.Assert(firstMappedInterval.InitialTime >= InitialTime);
HoloDebug.Assert(firstMappedInterval.InitialTime + firstMappedInterval.Duration <= InitialTime + DiscreteDuration);
TimedSlice <TTime, TValue> foundTimedSlice = GetInitialTimedSlice(firstMappedInterval);
Interval <TTime> intersection = foundTimedSlice.Interval.Intersect(firstMappedInterval);
HoloDebug.Assert(!intersection.IsEmpty);
Slice <TTime, TValue> ret = foundTimedSlice.Slice.Subslice(
intersection.InitialTime - foundTimedSlice.InitialTime,
intersection.Duration);
return(ret);
}
TimedSlice <TTime, TValue> GetInitialTimedSlice(Interval <TTime> firstMappedInterval)
{
// we must overlap somewhere
HoloDebug.Assert(!firstMappedInterval.Intersect(new Interval <TTime>(InitialTime, DiscreteDuration)).IsEmpty);
// Get the biggest available slice at firstMappedInterval.InitialTime.
// First, get the index of the slice just after the one we want.
TimedSlice <TTime, TValue> target = new TimedSlice <TTime, TValue>(firstMappedInterval.InitialTime, Slice <TTime, TValue> .Empty);
int originalIndex = _data.BinarySearch(target, TimedSlice <TTime, TValue> .Comparer.Instance);
int index = originalIndex;
if (index < 0)
{
// index is then the index of the next larger element
// -- we know there is a smaller element because we know firstMappedInterval fits inside stream interval
index = (~index) - 1;
HoloDebug.Assert(index >= 0);
}
TimedSlice <TTime, TValue> foundTimedSlice = _data[index];
return(foundTimedSlice);
}
