EncDotNet.S100.Datasets.S57 0.16.0

EncDotNet.S100.Datasets.S57

Reader and S-101 translator for IHO S-57 Electronic Navigational Chart (ENC) datasets.

Overview

This library reads S-57 (Edition 3.1) ENC base cells via the EncDotNet.S57 NuGet package (itself layered on top of EncDotNet.Iso8211) and translates the parsed records into the S-101 in-memory document model so the existing S-100 Part 9A Lua portrayal pipeline (provided by EncDotNet.S100.Datasets.S101) can render them. This is not an S-52 implementation — symbology is whatever the S-101 portrayal catalogue produces when fed the translated data.

Mappings follow the IHO S-57 to S-101 Conversion Guidance (S-101PT6 INF02A, draft 2021).

Key types:

• S57Dataset — entry point; opens a .000 file and exposes the parsed EncDotNet.S57.S57Document from the upstream package, plus a static IsS57File(path) discriminator used by EncDotNet.S100.Datasets.Pipelines to disambiguate .000 files that could otherwise be S-101.
• S57ToS101Translator — translates an S57Document (package type) into an S101Document by remapping object/attribute codes, exploding multi-point soundings, synthesising the information complex attribute from textual fields, and converting nodes/edges/area-rings into S-101 spatial primitives.
• S57S101Mapping — embedded code-mapping table sourced from IHO's S-57 → S-101 conversion guidance.
• S101AllowedEnumValues — lazy-loaded helper that consults the bundled S-101 Feature Catalogue to drop emitted enumerated attribute values that aren't permitted by the destination FC binding.

Translation behaviour

Limitations

• Base cells only. Update files (.001, .002, …) are not applied; the reader rejects them with a clear error.
• Breadth-first feature coverage. Most common feature classes map to S-101 acronyms; uncommon classes pass through unmapped and may not portray.
• Listed-value remapping is best-effort. Some S-57 enumerated attribute values have different numeric codes in S-101; values that aren't permitted by the destination S-101 FC binding are silently dropped.
• Complex-attribute synthesis is minimal. Sector lights and similar features that require S-101 nested complex attributes may not portray correctly.
• information is emitted directly on the feature (per the "generally" path in the conversion guidance) rather than via a separate NauticalInformation information type with an Additional Information association.

Validation

S57DatasetProcessor.Validate() runs validation in two phases:

1. Pre-translation — S57PreTranslationRules.Default checks the raw EncDotNet.S57.S57Document for things that don't survive translation (DSID / DSPM presence and a positive compilation scale; the presence of an M_COVR meta-feature).
2. Post-translation — the translated S-101 document is fed into S101DatasetRules.Default (the same pack that runs against native S-101 datasets) and the resulting findings are rebadged with the prefix S101-as-S57/ so the user can tell whether a problem originated in the raw S-57 input or in the translated S-101 projection.

Pre-translation rules shipped by S57PreTranslationRules.Default:

The two reports are concatenated by ConcatReports.Concat(pre, post, rebadgePrefix: "S101-as-S57/") in EncDotNet.S100.Datasets.Pipelines and cached on the processor.

Usage

using EncDotNet.S100.Datasets.S57;
using EncDotNet.S100.Datasets.S101;

var s57 = S57Dataset.Open("US5NY16M.000");
var s101Document = new S57ToS101Translator().Translate(s57);
var dataset = S101Dataset.FromDocument(s101Document);
// Use the existing S-101 pipeline from here:
// S101LuaRuleExecutor, S101FeatureGeometryProvider, etc.

Installation

dotnet add package EncDotNet.S100.Datasets.S57