Added some Geometry Processing methods with tests

Author: apdevelop

LinqToDBPostGisNetTopologySuite.Tests/GeometryProcessingTests.cs

@@ -144,7 +144,6 @@ public void TestSTFlipCoordinates()
             }
         }
 
-
         [Test]
         public void TestSTGeneratePoints()
         {
@@ -159,6 +158,81 @@ public void TestSTGeneratePoints()
             }
         }
 
+        [Test]
+        public void TestSTGeometricMedian()
+        {
+            using (var db = new PostGisTestDataConnection(TestDatabaseConnectionString))
+            {
+                const string wkt = "MULTIPOINT((0 0), (1 1), (2 2), (200 200))";
+                db.TestGeometries.Value(g => g.Id, 1).Value(p => p.Geometry, () => GeometryInput.STGeomFromText(wkt)).Insert();
+
+                var median = db.TestGeometries
+                    .Where(g => g.Id == 1)
+                    .Select(g => g.Geometry.STGeometricMedian())
+                    .Single() as NTSG.Point;
+
+                Assert.AreEqual(1.9761550281255, median.X, 1.0E-8);
+                Assert.AreEqual(1.9761550281255, median.Y, 1.0E-8);
+            }
+        }
+
+        [Test]
+        public void TestSTLineToCurve()
+        {
+            using (var db = new PostGisTestDataConnection(TestDatabaseConnectionString))
+            {
+                const string wkt = "POINT(1 3)";
+                db.TestGeometries
+                    .Value(g => g.Id, 1)
+                    .Value(p => p.Geometry, () =>
+                        GeometryInput.STGeomFromText(wkt).STBuffer(3.0))
+                    .Insert();
+
+                // NTS error: 'Geometry type not recognized. GeometryCode: 10'
+                var curvePolygon = db.TestGeometries
+                    .Where(g => g.Id == 1)
+                    .Select(g => g.Geometry.STLineToCurve().STAsText())
+                    .Single();
+
+                Assert.AreEqual("CURVEPOLYGON(CIRCULARSTRING(4 3,-2 2.99999999999999,4 3))", curvePolygon);
+            }
+        }
+
+        [Test]
+        public void TestSTMakeValid()
+        {
+            using (var db = new PostGisTestDataConnection(TestDatabaseConnectionString))
+            {
+                const string wkt1 = "LINESTRING(0 0,1 1)";
+                db.TestGeometries
+                    .Value(g => g.Id, 1)
+                    .Value(p => p.Geometry, () => GeometryInput.STGeomFromText(wkt1))
+                    .Insert();
+
+                const string wkt2 = "POLYGON((0 0, 1 1, 1 2, 1 1, 0 0))";
+                db.TestGeometries
+                    .Value(g => g.Id, 2)
+                    .Value(p => p.Geometry, () => GeometryInput.STGeomFromText(wkt2))
+                    .Insert();
+
+                var result1 = db.TestGeometries
+                    .Where(g => g.Id == 1)
+                    .Select(g => g.Geometry.STMakeValid().STAsText())
+                    .Single();
+
+                var result2 = db.TestGeometries
+                    .Where(g => g.Id == 2)
+                    .Select(g => g.Geometry.STMakeValid().STAsText())
+                    .Single();
+
+                // Already-valid geometries are returned without further intervention:
+                Assert.AreEqual(wkt1, result1);
+
+                // Single polygons may become multi-geometries in case of self-intersections:
+                Assert.AreEqual("MULTILINESTRING((0 0,1 1),(1 1,1 2))", result2);
+            }
+        }
+
         [Test]
         public void TestSTUnion()
         {
@@ -177,4 +251,4 @@ public void TestSTUnion()
             }
         }
     }
-}
+}

LinqToDBPostGisNetTopologySuite/GeometryProcessing.cs

@@ -246,7 +246,36 @@ public static NTSG STGeneratePoints(this NTSG geometry, int numberOfPoints, int
             throw new InvalidOperationException();
         }
 
+        /// <summary>
+        /// Returns approximate geometric median of input MultiPoint geometry using the Weiszfeld algorithm.
+        /// </summary>
+        /// <remarks>
+        /// See https://postgis.net/docs/manual-3.0/ST_GeometricMedian.html
+        /// </remarks>
+        /// <param name="geometry">Input geometry (MultiPoint)</param>
+        /// <param name="tolerance">Tolerance value</param>
+        /// <param name="maxIterations">Maximum number of iterations</param>
+        /// <param name="failIfNotConverged">Fail if not converged after maxIterations</param>
+        /// <returns>Geometric median</returns>
+        [Sql.Function("ST_GeometricMedian", ServerSideOnly = true)]
+        public static NTSG STGeometricMedian(this NTSG geometry, double tolerance, int maxIterations, bool failIfNotConverged)
+        {
+            throw new InvalidOperationException();
+        }
 
+        /// <summary>
+        /// Returns approximate geometric median of input MultiPoint geometry using the Weiszfeld algorithm.
+        /// </summary>
+        /// <remarks>
+        /// See https://postgis.net/docs/manual-3.0/ST_GeometricMedian.html
+        /// </remarks>
+        /// <param name="geometry">Input geometry (MultiPoint)</param>
+        /// <returns>Geometric median</returns>
+        [Sql.Function("ST_GeometricMedian", ServerSideOnly = true)]
+        public static NTSG STGeometricMedian(this NTSG geometry)
+        {
+            throw new InvalidOperationException();
+        }
 
         /// <summary>
         /// Returns geometry that represents the point set intersection of given geometries.
@@ -263,6 +292,36 @@ public static NTSG STIntersection(this NTSG geometry, NTSG other)
             throw new InvalidOperationException();
         }
 
+        /// <summary>
+        /// Converts plain input LineString/Polygon to CircularString/CurvePolygon.
+        /// </summary>
+        /// <remarks>
+        /// See https://postgis.net/docs/manual-3.0/ST_LineToCurve.html
+        /// </remarks>
+        /// <param name="geometry">Input geometry (LineString/Polygon)</param>
+        /// <returns>Curved equivalent of input geometry</returns>
+        [Sql.Function("ST_LineToCurve", ServerSideOnly = true)]
+        public static NTSG STLineToCurve(this NTSG geometry)
+        {
+            throw new InvalidOperationException();
+        }
+
+        /// <summary>
+        /// Attempts to create a valid representation of input invalid geometry without losing any of input vertices.
+        /// </summary>
+        /// <remarks>
+        /// See https://postgis.net/docs/manual-3.0/ST_MakeValid.html
+        /// </remarks>
+        /// <param name="geometry">Input geometry</param>
+        /// <returns>Fixed valid geometry</returns>
+        [Sql.Function("ST_MakeValid", ServerSideOnly = true)]
+        public static NTSG STMakeValid(this NTSG geometry)
+        {
+            throw new InvalidOperationException();
+        }
+
+        // TODO: ST_MemUnion(geometry set)
+
         /// <summary>
         /// Returns POINT guaranteed to intersect a surface.
         /// </summary>
@@ -293,7 +352,7 @@ public static NTSG STSymDifference(this NTSG geometry, NTSG other)
         }
 
         /// <summary>
-        /// Returns union of given geometries.
+        /// Returns union of input geometries.
         /// </summary>
         /// <remarks>
         /// See https://postgis.net/docs/manual-3.0/ST_Union.html
@@ -307,4 +366,4 @@ public static NTSG STUnion(this NTSG geometry, NTSG other) // TODO: other varian
             throw new InvalidOperationException();
         }
     }
-}
+}