Class S57Dataset

Namespace

EncDotNet.S100.Datasets.S57

Assembly

EncDotNet.S100.Datasets.S57.dll

Thin wrapper over S57Document from the upstream EncDotNet.S57 package. Provides the IsS57File(string) discriminator used by DatasetPipelineFactory to disambiguate .000 files between S-57 and S-101 (which share the extension and ISO 8211 envelope).

public sealed class S57Dataset

Inheritance

object

S57Dataset

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Properties

DatasetName

Dataset name from the DSID record.

public string DatasetName { get; }

Property Value

string

DeclaredProductSpecification

The S-57 product specification the dataset declares in its DSID PRSP subfield (see S57ProductSpecification), or 0 when it declares none.

public int DeclaredProductSpecification { get; }

Property Value

int

Document

The underlying parsed S-57 document (from the package).

public S57Document Document { get; }

Property Value

S57Document

FeatureCount

Number of feature records in the dataset.

public int FeatureCount { get; }

Property Value

int

TranslationTarget

The S-100 product this dataset should be translated into: S401 for a cell declaring InlandElectronicNavigationalChart, otherwise S101.

public S57TranslationTarget TranslationTarget { get; }

Property Value

S57TranslationTarget

UpdateReport

What happened to the updates when the cell was opened with Open(Stream, IReadOnlyList<Stream>); otherwise null.

public S57UpdateReport? UpdateReport { get; }

Property Value

S57UpdateReport

Methods

DeclaredProductSpecificationOf(S57Document)

The S-57 product specification document declares in its DSID PRSP subfield, or 0 when it has no DSID.

public static int DeclaredProductSpecificationOf(S57Document document)

Parameters

document S57Document

The parsed S-57 document.

Returns

int

IsS57File(string)

Returns true when the file at path appears to be an S-57 dataset (heuristic: the ISO 8211 DDR contains a DSPM field, which is unique to S-57 and not present in S-101). Returns false for non-ISO 8211 files or files lacking DSPM.

public static bool IsS57File(string path)

Parameters

path string

Returns

bool

Open(Stream)

Opens an S-57 base cell from a stream.

public static S57Dataset Open(Stream stream)

Parameters

stream Stream

Returns

S57Dataset

Open(Stream, IReadOnlyList<Stream>)

Opens an S-57 base cell from baseStream and applies the sequential update datasets in updateStreams with S57UpdateApplicator.

public static S57Dataset Open(Stream baseStream, IReadOnlyList<Stream> updateStreams)

Parameters

baseStream Stream

The base cell (.000) stream.

updateStreams IReadOnlyList<Stream>

The update streams, in ascending update-number order.

Returns

S57Dataset

Remarks

Updates are applied while they're for the cell's edition and follow on from each other; the first that doesn't stops the sequence, and an update with edition 0 cancels the cell. What happened is in UpdateReport, and never stops the cell from opening.

Open(string)

Opens an S-57 base cell from a file path.

public static S57Dataset Open(string path)

Parameters

path string

Returns

S57Dataset

ReadMetadata()

Produces the lightweight DatasetMetadata for this already parsed dataset: the canonical S-57 specification, the geographic extent, and the whole-cell display window (issue #460).

public DatasetMetadata ReadMetadata()

Returns

DatasetMetadata

The cell's lightweight metadata.

Remarks

The phased win over a full load is that the S-57 → S-101 translation and the portrayal catalogue are never touched: the extent is folded directly from the raw spatial records' coordinates (2-D vertices and sounding nodes), divided by the coordinate multiplication factor (COMF) from the DSPM field to yield WGS-84 decimal degrees. This mirrors the extent the full render ultimately fits, but skips S-101 feature/attribute materialisation (the display window reads only the raw SCAMIN attribute values).

The display-scale window carries only a coarsest bound, from ResolveCellMinimumDisplayScale(S57Document) (the larger of the compilation scale and the largest feature SCAMIN) — the same value the full processor applies as the whole-cell minimum display scale. The canonical spec name is S-57 with a default edition, matching S57DatasetProcessor.Spec.

ReadMetadata(S57Document)

Produces the lightweight DatasetMetadata for an already-parsed (and, where applicable, update-folded) S57Document. Exposed so the render pipeline's S57DatasetProcessor can surface the same metadata from the merged document it already holds, without re-opening the cell.

public static DatasetMetadata ReadMetadata(S57Document document)

Parameters

document S57Document

The parsed S-57 document.

Returns

DatasetMetadata

The document's lightweight metadata.

Exceptions

ArgumentNullException

document is null.

ReadMetadata(Stream)

Reads only the lightweight DatasetMetadata for an S-57 base cell from stream. See ReadMetadata() for the phased-loading rationale.

public static DatasetMetadata ReadMetadata(Stream stream)

Parameters

stream Stream

The S-57 base cell (.000) stream.

Returns

DatasetMetadata

The cell's lightweight metadata.

ReadMetadata(string)

Reads only the lightweight DatasetMetadata for an S-57 base cell at path — its (canonical) specification, geographic extent, and intended display-scale window — for phased / deferred loading (issue #460). See ReadMetadata() for the rationale and the cheap-scan strategy.

public static DatasetMetadata ReadMetadata(string path)

Parameters

path string

Absolute path to the S-57 base cell (.000).

Returns

DatasetMetadata

The cell's lightweight metadata.

ResolveCellMinimumDisplayScale(S57Document)

Resolves an S-57 cell's whole-cell zoom-out window: the coarsest (largest-denominator) scale at which any of its content is intended to be displayed. This is the larger of the compilation scale (CSCL, DSPM field, S-57 Appendix B.1 §7.3.1.1) and the largest feature SCAMIN (S-57 Appendix A attribute 133) in the cell.

public static int? ResolveCellMinimumDisplayScale(S57Document document)

Parameters

document S57Document

The parsed (and, where applicable, update-folded) S-57 document.

Returns

int?

The window denominator, or null when the cell declares neither a positive compilation scale nor any positive SCAMIN.

Remarks

S-57 carries no minimum display scale. The compilation scale is the largest intended viewing scale — S-52 §3.1.7 uses it only for the overscale indication — and S-65 Annex B §2.1.6 maps it to the S-101 optimum display scale while leaving minimumDisplayScale null. Capping the cell at CSCL therefore hid content the producer encoded to remain visible further out: NOAA SCAMIN values run to 3–5× CSCL, and USACE inland cells (CSCL 1:5,000) to 1:300,000. The largest SCAMIN is the producer's own coarsest visibility statement, so beyond it no feature would draw anyway; features without SCAMIN (area fills, coverage) stay visible up to it.

The compilation scale remains the cell's ranking scale against overlapping cells; see ResolveCompilationScale(S57Document).

Exceptions

ArgumentNullException

document is null.

ResolveCompilationScale(S57Document)

Resolves an S-57 cell's compilation scale (CSCL, DSPM field, S-57 Appendix B.1 §7.3.1.1) — the analogue of the S-101 optimum display scale (S-65 Annex B §2.1.6) used to rank overlapping cells (a smaller denominator is the finer cell).

public static int? ResolveCompilationScale(S57Document document)

Parameters

document S57Document

The parsed S-57 document.

Returns

int?

The positive compilation scale denominator, or null.

Exceptions

ArgumentNullException

document is null.

TranslationTargetFor(S57Document)

The S-100 product document should be translated into, chosen from the S-57 product specification it declares (see TranslationTarget).

public static S57TranslationTarget TranslationTargetFor(S57Document document)

Parameters

document S57Document

The parsed S-57 document.

Returns

S57TranslationTarget