public RowCursor(IChannelProvider provider, int poolRows, IRowCursor input, IRandom rand)
: base(provider)
{
Ch.AssertValue(input);
Ch.AssertValue(rand);
Ch.Assert(_blockSize > 0);
Ch.Assert(_bufferDepth > 0);
Ch.Assert(poolRows > 0);
_poolRows = poolRows;
_input = input;
_rand = rand;
_pipeIndices = Utils.GetIdentityPermutation(_poolRows - 1 + _bufferDepth * _blockSize);
int colLim = Schema.ColumnCount;
int numActive = 0;
_colToActivesIndex = new int[colLim];
for (int c = 0; c < colLim; ++c)
{
_colToActivesIndex[c] = _input.IsColumnActive(c) ? numActive++ : -1;
}
_pipes = new ShufflePipe[numActive + (int)ExtraIndex.Lim];
_getters = new Delegate[numActive];
for (int c = 0; c < colLim; ++c)
{
int ia = _colToActivesIndex[c];
if (ia < 0)
{
continue;
}
_pipes[ia] = ShufflePipe.Create(_pipeIndices.Length,
input.Schema.GetColumnType(c), RowCursorUtils.GetGetterAsDelegate(input, c));
_getters[ia] = CreateGetterDelegate(c);
}
var idPipe = _pipes[numActive + (int)ExtraIndex.Id] = ShufflePipe.Create(_pipeIndices.Length, NumberType.UG, input.GetIdGetter());
_idGetter = CreateGetterDelegate <UInt128>(idPipe);
// Initially, after the preamble to MoveNextCore, we want:
// liveCount=0, deadCount=0, circularIndex=0. So we set these
// funky values accordingly.
_pipeIndex = _circularIndex = _pipeIndices.Length - 1;
_deadCount = -1;
_liveCount = 1;
// Set up the producer worker.
_toConsume = new BufferBlock <int>();
_toProduce = new BufferBlock <int>();
// First request the pool - 1 + block size rows, to get us going.
PostAssert(_toProduce, _poolRows - 1 + _blockSize);
// Queue up the remaining capacity.
for (int i = 1; i < _bufferDepth; ++i)
{
PostAssert(_toProduce, _blockSize);
}
_producerTask = LoopProducerWorker();
}
public Row GetOutputRow(Row input, Func <int, bool> predicate, out Action disposer)
{
Contracts.AssertValue(input);
Contracts.AssertValue(predicate);
var totalColumnsCount = 1 + _outputGenericSchema.ColumnCount;
var getters = new Delegate[totalColumnsCount];
if (predicate(totalColumnsCount - 1))
{
getters[totalColumnsCount - 1] = _parent.Stringify
? _parent.GetTextContributionGetter(input, InputRoleMappedSchema.Feature.Index, _slotNames)
: _parent.GetContributionGetter(input, InputRoleMappedSchema.Feature.Index);
}
var genericRow = _genericRowMapper.GetRow(input, GetGenericPredicate(predicate), out disposer);
for (var i = 0; i < _outputGenericSchema.ColumnCount; i++)
{
if (genericRow.IsColumnActive(i))
{
getters[i] = RowCursorUtils.GetGetterAsDelegate(genericRow, i);
}
}
return(new SimpleRow(OutputSchema, input, getters));
}