Use a single GeometryFactory instance

Author: CorruptComputer

Alidade.Core/AlidadeCoreModule.cs

@@ -1,4 +1,6 @@
+using Alidade.Core.Consts;
 using Autofac;
+using NetTopologySuite.Geometries;
 
 namespace Alidade.Core;
 
@@ -11,5 +13,9 @@ public sealed class AlidadeCoreModule : Module
     protected override void Load(ContainerBuilder builder)
     {
         builder.RegisterType<SettingsStateService>().AsSelf().SingleInstance();
+
+        builder.RegisterInstance(new GeometryFactory(new PrecisionModel(), SpatialReferenceIDs.Wgs84))
+               .AsSelf()
+               .SingleInstance();
     }
 }

Alidade.Core/Consts/SpatialReferenceIDs.cs

@@ -0,0 +1,12 @@
+namespace Alidade.Core.Consts;
+
+/// <summary>
+///   EPSG spatial reference system identifiers.
+/// </summary>
+public static class SpatialReferenceIDs
+{
+    /// <summary>
+    ///   WGS 84 geographic coordinate system, EPSG:4326
+    /// </summary>
+    public const int Wgs84 = 4326;
+}

Alidade.Osm/Models/Imagery/ImageryEntry.cs

@@ -1,5 +1,6 @@
 using System.Text.Json.Serialization;
 using System.Text.RegularExpressions;
+using Alidade.Core.Consts;
 using NetTopologySuite;
 using NetTopologySuite.Geometries;
 
@@ -75,16 +76,13 @@ public int? MaxZoom
     ///   Builds an NTS <see cref="Geometry"/> for the coverage polygons,
     ///   or returns null for worldwide sources.
     /// </summary>
-    public Geometry? BuildCoverageGeometry()
+    public Geometry? BuildCoverageGeometry(GeometryFactory factory)
     {
         if (Polygon is not { Length: > 0 })
         {
             return null;
         }
 
-        GeometryFactory factory = NtsGeometryServices.Instance
-            .CreateGeometryFactory(srid: 4326);
-
         Polygon[] polys = [.. Polygon.Select(ring =>
         {
             Coordinate[] coords = [.. ring.Select(p => new Coordinate(p[0], p[1]))];

Alidade.Osm/Models/OsmGeoJsonExtensions.cs

@@ -1,3 +1,6 @@
+using NetTopologySuite.Features;
+using NetTopologySuite.Geometries;
+
 namespace Alidade.Osm.Models;
 
 /// <summary>
@@ -17,7 +20,7 @@ namespace Alidade.Osm.Models;
 /// <param name="Lat">Latitude in decimal degrees (WGS 84), in the range −90 to +90.</param>
 /// <param name="Lon">Longitude in decimal degrees (WGS 84), in the range −180 to +180.</param>
 /// <param name="Tags">Key-value pairs describing the node. Empty for geometry-only nodes (e.g. way vertices).</param>
-public record OsmNode(
+public sealed record OsmNode(
     long Id,
     int Version,
     int? ChangesetId,
@@ -31,4 +34,30 @@ public record OsmNode(
     ///   Returns a typed reference to this node.
     /// </summary>
     public OsmElementRef Ref => new(OsmElementTypes.Node, Id);
+
+    /// <summary>
+    ///   Converts this to an NTS <see cref="Feature"/> with a Point geometry.
+    ///   Tag key/value pairs are stored as attributes prefixed with <c>tag:</c>.
+    /// </summary>
+    /// <param name="factory">The geometry factory used to construct the Point.</param>
+    /// <returns>A GeoJSON-serializable Point <see cref="Feature"/>.</returns>
+    public Feature ToFeature(GeometryFactory factory)
+    {
+        AttributesTable attrs = new()
+        {
+            { "id", Id.ToString() },
+            { "type", "node" },
+            { "version", Version },
+            { "editState", (int)EditState.Fetched },
+            { "fill", "#fff" },
+            { "stroke", "#555" }
+        };
+
+        foreach ((string k, string v) in Tags)
+        {
+            attrs.Add("tag:" + k, v);
+        }
+
+        return new Feature(factory.CreatePoint(new Coordinate(Lon, Lat)), attrs);
+    }
 }