s125-aton

name: s125-aton description: | Expert knowledge of IHO S-125 Marine Aids to Navigation Product Specification. Covers GML encoding (S-100 Part 10b) using the S-100 GML 5.0 profile, the S-125 application schema (lights, buoys, beacons, daymarks, AIS aids), AtoN status indication and status information types, xlink-based information bindings, and the XSLT-based portrayal pipeline. USE FOR: S-125 datasets, marine aids to navigation, GML parsing for S-125, XSLT portrayal of AtoN, vector pipeline changes affecting S-125, S-125 reader/source code, S-125 tests. DO NOT USE FOR: S-101 ENC AtoN feature classes (use s101-enc), S-124 navigational warnings (use s124-nav-warnings), generic GML (use s100-framework).

S-125 Marine Aids to Navigation expert

When engaged

• Tasks touching src/EncDotNet.S100.Datasets.S125/** or tests/EncDotNet.S100.Datasets.S125.Tests/**
• GML/XSLT portrayal changes for AtoN
• Vector pipeline changes affecting S-125
• Bundled S-125 spec asset updates under src/EncDotNet.S100.Specifications/content/S125/

Spec anchors

• Canonical: S-125 Edition 1.0.0 Marine Aids to Navigation PS (development repo: https://github.com/iho-ohi/S-125-Product-Specification-Development)
• S-100 Part 10b: GML encoding (S-100 GML 5.0 profile)
• S-100 Part 9: Portrayal (XSLT path)
• S-125 Annex A: Feature Catalogue
• S-125 Annex B: Portrayal Catalogue

Concrete feature classes (Edition 1.0.0)

• Buoys: LateralBuoy, CardinalBuoy, IsolatedDangerBuoy, SafeWaterBuoy, SpecialPurposeGeneralBuoy, EmergencyWreckMarkingBuoy, MooringBuoy, InstallationBuoy
• Beacons: LateralBeacon, CardinalBeacon, IsolatedDangerBeacon, SafeWaterBeacon, SpecialPurposeGeneralBeacon
• Lights: LightAllAround, LightSectored, LightAirObstruction, LightFloat, LightVessel, LightFogDetector
• Structures: Landmark, Daymark, OffshorePlatform, Pile, SiloTank, WindTurbine, Topmark
• Signals & equipment: FogSignal, RadarReflector, Retroreflector, RadarTransponderBeacon, RadioStation
• AIS: PhysicalAISAidToNavigation, SyntheticAISAidToNavigation, VirtualAISAidToNavigation
• Lines/areas: NavigationLine, RecommendedTrack, LocalDirectionOfBuoyage, NavigationalSystemOfMarks, DangerousFeature, DataCoverage, QualityOfBathymetricData, SoundingDatum, VerticalDatumOfData
• Aggregations: AtonAggregation, AtonAssociation, AtonStatusIndication

Concrete information types

• AtonStatusInformation — AtoN change/status payload
• SpatialQuality — positional accuracy metadata

Review checklist

1. GML parsing tolerates both s100gml/5.0 and the older s100gml/1.0 (lower-case and S100/profile/s100gml/1.0) namespaces; do not hard-code one.
2. Coordinate ordering in <gml:pos> / <gml:posList> is lat lon for EPSG:4326 (S-100 Part 10b convention).
3. Information references on features (e.g. <AtoNStatus xlink:href="#info1"/>) preserve role name + trimmed identifier so the bundled XSLT can resolve them with id($ref) semantics.
4. The synthesised FeatureXML neutral form must include both <Dataset><Features> and <Dataset><InformationTypes> blocks, with information references emitted as <RoleName informationRef="…"/> children of the feature.
5. Container objects (AtonAggregation, AtonAssociation) carry no geometry — renderer must tolerate geometry-less features.
6. Portrayal goes through XSLT (no Lua). Top-level template is main.xsl; sub-templates load via xsl:include (resolved by the catalogue's XmlResolver).
7. Time validity (fixedDateRange, periodicDateRange) is UTC; do not coerce to local time at the source boundary.
8. Public API changes have xunit tests; synthetic GML fixtures live under tests/datasets/S125/.

Known pitfalls in this repo

• The bundled S-125 1.0.0 development PC is preliminary. It ships only AtoN status indication, AtoN status information, and DataCoverage rules. Most concrete feature classes therefore render as the QUESMRK1 question-mark fallback. Don't treat that as a parser bug.
• The XSLT references the association role with capital N (AtoNStatus) while the FC information-type code uses lowercase n (AtonStatusInformation). The reader and feature-XML projection must round-trip the role name as written in the dataset, not normalise it.
• The S-125 schema uses <Dataset> (single capital) as the root element, not <DataSet> as in S-124.
• AtoNStatus references appear as empty elements with xlink:href; the reader filters child-less elements with no text content as information references rather than simple attributes.