Class S102CoverageSource

Namespace

EncDotNet.S100.Datasets.S102

Assembly

EncDotNet.S100.Datasets.S102.dll

Adapts an S-102 S102Dataset to the pipeline-facing ICoverageSource. Supports the coverage overview pyramid (issue #486): when a level > 0 is selected via SelectOverviewLevel(int) the pyramid is built lazily on first access with MinReducer for depth (shoal-biased) and MaxReducer for uncertainty (worst-case). Residual viewport stride applies equivalent reductions over balanced blocks that preserve the sampled footprint's regular georeferencing.

public class S102CoverageSource : ICoverageSource

Inheritance

object

S102CoverageSource

Implements

ICoverageSource

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Constructors

S102CoverageSource(S102Dataset, int)

Creates a coverage source over one bathymetry coverage of an S-102 dataset. The overview pyramid is not built until a level other than the base level is requested.

public S102CoverageSource(S102Dataset dataset, int coverageIndex = 0)

Parameters

dataset S102Dataset

The parsed S-102 dataset.

coverageIndex int

Index into Coverages of the coverage to expose. Defaults to the first coverage.

Fields

FillValue

S-102 standard fill value for no-data cells.

public const float FillValue = 1000000

Field Value

float

MaxPyramidLevels

Maximum number of pyramid levels (base + downsampled). Cap = 6 gives 64× reduction per axis; a 2048×2048 tile shrinks to 32×32. Approved in issue #486 review.

public const int MaxPyramidLevels = 6

Field Value

int

Properties

AvailableOverviewLevels

The overview levels this source can serve, in increasing order. Level 0 is always the native (base) grid; higher levels are downsampled (level N = 2^N × coarser per axis). Sources without an overview pyramid return a single-element list describing the base grid.

public IReadOnlyList<CoverageOverviewLevel> AvailableOverviewLevels { get; }

Property Value

IReadOnlyList<CoverageOverviewLevel>

AvailableTimes

The time steps this coverage can be sampled at, in the order the dataset stores them. Empty for static products (S-102); populated for time-varying products (S-104, S-111).

public IReadOnlyList<DateTime> AvailableTimes { get; }

Property Value

IReadOnlyList<DateTime>

Remarks

S-102 has no time dimension, so this list is always empty.

Coverage

The single bathymetry coverage instance this source exposes.

public BathymetryCoverage Coverage { get; }

Property Value

BathymetryCoverage

Dataset

The underlying S-102 dataset wrapped by this source.

public S102Dataset Dataset { get; }

Property Value

S102Dataset

Metadata

File-level metadata: extent, grid geometry, CRS, no-data sentinel and the value fields the source carries. Available immediately after the source is constructed.

public CoverageMetadata Metadata { get; }

Property Value

CoverageMetadata

Remarks

Implementations may build a new instance on every read. The GridMetadata reflects the currently selected overview level (see SelectOverviewLevel(int)).

SelectedOverviewLevel

The level index currently selected by SelectOverviewLevel(int). Defaults to 0 (base grid).

public int SelectedOverviewLevel { get; }

Property Value

int

Spec

The dataset's declared product specification, resolved from DeclaredProductSpecification; the edition is default (unknown) when the file declares none.

public SpecRef Spec { get; }

Property Value

SpecRef

Methods

Sample(GridRegion, CancellationToken)

Copies the requested grid region into a SampledCoverage. The underlying grid is already resident in memory (the HDF5 read happens at construction time), so this is a CPU-bound copy rather than an I/O operation; cancellationToken lets a large copy be abandoned cooperatively. The method remains synchronous.

public virtual SampledCoverage Sample(GridRegion region, CancellationToken cancellationToken = default)

Parameters

region GridRegion

The grid subset and stride to sample.

cancellationToken CancellationToken

Signals that the render has been cancelled.

Returns

SampledCoverage

The sampled values for every field in ValueFields, at the currently selected time step and overview level. The result's Metadata describes the geometry of the sampled sub-grid itself (output row/column count, origin and spacing in the native CRS), so GetPosition(int, int) locates each output cell. How cells skipped by a stride greater than one are combined (plain decimation or a reduction such as S-102's shoalest-depth minimum) is source-specific. An empty region yields a zero-cell sample.

Remarks

Samples the currently selected overview level. When the region's stride skips cells, depth is reduced to the shoalest value (minimum) and uncertainty to the worst case (maximum) within each block.

Exceptions

OperationCanceledException

cancellationToken was cancelled during the copy.

SelectOverviewLevel(int)

Selects the overview level to serve on subsequent Metadata reads and Sample(GridRegion, CancellationToken) calls. After the call, Metadata's GridMetadata reflects the level's rows/cols/spacing so viewport-derived GridRegions pick up the correct geometry automatically. Sources without a pyramid must accept level == 0 as a no-op; other values may throw or be silently clamped (see the source's documentation).

public void SelectOverviewLevel(int level)

Parameters

level int

Zero-based level index, expected to be in [0, AvailableOverviewLevels.Count - 1].

SelectTime(DateTime)

Selects the time step served by subsequent Sample(GridRegion, CancellationToken) calls.

public void SelectTime(DateTime time)

Parameters

time DateTime

The requested time. Time-varying sources select the exact match in AvailableTimes when present, otherwise the nearest available time step. Static sources treat the call as a no-op.

Remarks

Does nothing: S-102 has no time dimension.