| name | s122-marine-protected-areas |
| description | Expert knowledge of IHO S-122 Marine Protected Areas Product
Specification (Edition 2.0.0). Covers GML encoding (S-100 Part 10b)
over the S-100 GML base, the S-122 application schema (marine
protected areas, restricted areas, regulated areas, and associated
text placement), and the XSLT-based portrayal pipeline. USE FOR:
S-122 datasets, marine protected areas, restricted/regulated areas,
GML parsing for S-122, XSLT portrayal of S-122, vector pipeline
changes affecting S-122, S122DatasetReader / S-122 reader/source
code, S-122 tests, edits to bundled `content/S122/**` assets.
DO NOT USE FOR: S-127 marine resources and services (use
s127-marine-services), S-124 nav warnings (use s124-nav-warnings),
S-125 AtoN (use s125-aton), S-101 ENC (use s101-enc), generic GML /
framework concerns (use s100-framework).
|
S-122 Marine Protected Areas expert
When engaged
- Tasks touching
src/EncDotNet.S100.Datasets.S122/** or
tests/EncDotNet.S100.Datasets.S122.Tests/**
- Edits to bundled portrayal assets under
src/EncDotNet.S100.Specifications/content/S122/**
- GML/XSLT portrayal changes for marine protected areas
- Vector pipeline changes (
IVectorSource, VectorPipeline)
affecting S-122
Spec anchors
- Canonical: S-122 Edition 2.0.0 Marine Protected Areas PS
- S-100 Part 10b: GML encoding
- S-100 Part 9: Portrayal (XSLT path)
- S-122 Feature/Information Catalogue (FC 2.0.0) + published XSD
- Upstream PC:
iho-ohi/S-122-Product-Specification-Development
Review checklist
- Product detection is identifier-driven, not namespace-driven.
The official 2.0.0 sample is mis-labelled with the S-123
namespace prefix on the dataset root
(
xmlns:S123="http://www.iho.int/S123/gml/1.0"). Detection must
key on the S-100 <productIdentifier>S-122…</productIdentifier>
element — keep that fallback in DatasetPipelineFactory.
- Tolerate every s100gml namespace variant seen across releases
(
http://www.iho.int/s100gml/1.0,
http://www.iho.int/S100/profile/s100gml/1.0,
http://www.iho.int/s100gml/5.0) via
S122DatasetReader.DetectS100Namespace — do not hard-code one.
- Coordinate ordering in
<gml:pos> / <gml:posList> is lat lon
for EPSG:4326 (S-100 Part 10b §6.2).
- Support both the standard
<member>/<imember> wrappers and
the inline <members>/<imembers> containers. Iterate descendants
of the dataset root and match by feature/information type code.
- Portrayal goes through XSLT (not Lua); inputs to the transform must
be the canonical GML, and transforms must stay within features
supported by .NET's
XslCompiledTransform.
- Renderers must tolerate geometry-less features (e.g.
TextPlacement may attach to a referenced feature rather than carry
its own geometry).
- Public API changes have xunit tests using the official sample under
tests/datasets/S122/.
Known pitfalls in this repo (producer-bug compensation)
S122DatasetReader already auto-corrects two real-world quirks; new
geometry parsing code must preserve both:
- lon-lat
posList vs. lat-lon envelope. The UKHO trial dataset
emits <gml:posList> in lon-lat order while keeping the
<gml:Envelope> corners correctly in lat-lon. The reader samples
parsed coords against the declared envelope and swaps every feature
when the as-parsed interpretation clearly falls outside but the
swapped one fits. Keep the heuristic conservative (≤25 % as-is fit,
≥75 % swapped fit) so spec-conformant samples are untouched.
- Comma-separated tuples in
posList. Some producers emit
lon,lat lon,lat … tokens (the gml:coordinates convention)
instead of all-whitespace. ParsePos / ParsePosList treat both
whitespace and commas as separators — do not regress that.
Portrayal / palette caveats
- The bundled
content/S122/pc/ tree is intended to be
byte-identical to upstream (PC 2.0.0). Do not edit those files.
If the upstream main.xsl ever needs adapting for this codebase's
display-list dialect, add a small adapter XSLT alongside it (mirror
the S-411 Adapter/main.xsl pattern).
- The v2.0.0 PC ships only a
Day <palette> block in
colorProfile.xml, so palette switching to Dusk/Night is currently a
no-op for S-122. Do not modify the upstream colorProfile.xml; if
local Dusk/Night palettes are needed before upstream publishes them,
synthesise them in code and document it explicitly.
Cite your sources
Cite the S-122 section number (or upstream catalogue path) in XML doc
comments when adding spec-derived constants or element names.
