Golang RLEs.Split方法代码示例

// SplitLabels splits a portion of a label's voxels into a given split label or, if the given split
// label is 0, a new label, which is returned.  The input is a binary sparse volume and should
// preferably be the smaller portion of a labeled region.  In other words, the caller should chose
// to submit for relabeling the smaller portion of any split.  It is assumed that the given split
// voxels are within the fromLabel set of voxels and will generate unspecified behavior if this is
// not the case.
//
// EVENTS
//
// labels.SplitStartEvent occurs at very start of split and transmits labels.DeltaSplitStart struct.
//
// labels.SplitBlockEvent occurs for every block of a split label and transmits labels.DeltaSplit struct.
//
// labels.SplitEndEvent occurs at end of split and transmits labels.DeltaSplitEnd struct.
//
func (d *Data) SplitLabels(v dvid.VersionID, fromLabel, splitLabel uint64, r io.ReadCloser) (toLabel uint64, err error) {
	store, err := d.GetOrderedKeyValueDB()
	if err != nil {
		err = fmt.Errorf("Data type labelvol had error initializing store: %v\n", err)
		return
	}
	batcher, ok := store.(storage.KeyValueBatcher)
	if !ok {
		err = fmt.Errorf("Data type labelvol requires batch-enabled store, which %q is not\n", store)
		return
	}

	// Create a new label id for this version that will persist to store
	if splitLabel != 0 {
		toLabel = splitLabel
		dvid.Debugf("Splitting subset of label %d into given label %d ...\n", fromLabel, splitLabel)
	} else {
		toLabel, err = d.NewLabel(v)
		if err != nil {
			return
		}
		dvid.Debugf("Splitting subset of label %d into new label %d ...\n", fromLabel, toLabel)
	}

	evt := datastore.SyncEvent{d.DataUUID(), labels.SplitStartEvent}
	splitOpStart := labels.DeltaSplitStart{fromLabel, toLabel}
	splitOpEnd := labels.DeltaSplitEnd{fromLabel, toLabel}

	// Make sure we can split given current merges in progress
	if err := labels.SplitStart(d.getMergeIV(v), splitOpStart); err != nil {
		return toLabel, err
	}
	defer labels.SplitStop(d.getMergeIV(v), splitOpEnd)

	// Signal that we are starting a split.
	msg := datastore.SyncMessage{labels.SplitStartEvent, v, splitOpStart}
	if err := datastore.NotifySubscribers(evt, msg); err != nil {
		return 0, err
	}

	// Read the sparse volume from reader.
	var split dvid.RLEs
	split, err = dvid.ReadRLEs(r)
	if err != nil {
		return
	}
	toLabelSize, _ := split.Stats()

	// Partition the split spans into blocks.
	var splitmap dvid.BlockRLEs
	splitmap, err = split.Partition(d.BlockSize)
	if err != nil {
		return
	}

	// Get a sorted list of blocks that cover split.
	splitblks := splitmap.SortedKeys()

	// Iterate through the split blocks, read the original block.  If the RLEs
	// are identical, just delete the original.  If not, modify the original.
	// TODO: Modifications should be transactional since it's GET-PUT, therefore use
	// hash on block coord to direct it to blockLabel, splitLabel-specific goroutine; we serialize
	// requests to handle concurrency.
	ctx := datastore.NewVersionedCtx(d, v)
	batch := batcher.NewBatch(ctx)

	for _, splitblk := range splitblks {

		// Get original block
		tk := NewTKey(fromLabel, splitblk)
		val, err := store.Get(ctx, tk)
		if err != nil {
			return toLabel, err
		}

		if val == nil {
			return toLabel, fmt.Errorf("Split RLEs at block %s are not part of original label %d", splitblk, fromLabel)
		}
		var rles dvid.RLEs
		if err := rles.UnmarshalBinary(val); err != nil {
			return toLabel, fmt.Errorf("Unable to unmarshal RLE for original labels in block %s", splitblk)
		}

		// Compare and process based on modifications required.
		remain, err := rles.Split(splitmap[splitblk])
//.........这里部分代码省略.........