Geometry_Engine: implement GeometryHash

BHoM_Engine/Query/GeometryHash.cs

@@ -0,0 +1,74 @@
+/*
+ * This file is part of the Buildings and Habitats object Model (BHoM)
+ * Copyright (c) 2015 - 2022, the respective contributors. All rights reserved.
+ *
+ * Each contributor holds copyright over their respective contributions.
+ * The project versioning (Git) records all such contribution source information.
+ *                                           
+ *                                                                              
+ * The BHoM is free software: you can redistribute it and/or modify         
+ * it under the terms of the GNU Lesser General Public License as published by  
+ * the Free Software Foundation, either version 3.0 of the License, or          
+ * (at your option) any later version.                                          
+ *                                                                              
+ * The BHoM is distributed in the hope that it will be useful,              
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of               
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                 
+ * GNU Lesser General Public License for more details.                          
+ *                                                                            
+ * You should have received a copy of the GNU Lesser General Public License     
+ * along with this code. If not, see <https://www.gnu.org/licenses/lgpl-3.0.html>.      
+ */
+
+using BH.oM.Base;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Security.Cryptography;
+using System.Reflection;
+using BH.oM.Base.Attributes;
+using System.ComponentModel;
+using BH.Engine.Base;
+using System.Collections;
+using System.Data;
+using BH.oM.Geometry;
+
+namespace BH.Engine.Base
+{
+    public static partial class Query
+    {
+        /***************************************************/
+        /****               Public Methods              ****/
+        /***************************************************/
+
+        [Description("Returns the geometrical identity of any IBHoMObject, useful for distance-based comparisons and diffing. " +
+            "\nThe geometrical identity is computed by extracting the geometry of the object via the IGeometry() method." +
+            "\nThen, the hash is computed as an array representing the coordinate of significant points taken on the geometry." +
+            "\nThe number of points is reduced to the minimum essential to determine uniquely any geometry." +
+            "\nAdditionally, the resulting points are transformed based on the source geometry type, to remove or minimize collisions." +
+            "\n(Any transformation so performed is translational only, in order to support geometrical tolerance, i.e. numerical distance, when comparing GeometryHashes downstream).")]
+        [Input("bhomObj", "Input BHoMObject whose geometry will be queried by IGeometry() and which will be used for computing a Geometry Hash.")]
+        [Output("geomHash","Array of numbers representing a unique signature of the input object's geometry.")]
+        public static double[] GeometryHash(this IBHoMObject bhomObj)
+        {
+            IGeometry igeom = bhomObj.IGeometry();
+
+            if (igeom == null)
+                return null;
+
+            if (m_GeomHashFunc == null)
+            {
+                MethodInfo mi = Query.ExtensionMethodToCall(igeom, "IGeometryHash");
+                m_GeomHashFunc = (Func<IGeometry, double[]>)Delegate.CreateDelegate(typeof(Func<IGeometry, double[]>), mi);
+            }
+
+            return m_GeomHashFunc(igeom);
+        }
+
+        private static Func<IGeometry, double[]> m_GeomHashFunc = null;
+    }
+}
+
+

Geometry_Engine/Query/FaceIndices.cs

@@ -0,0 +1,56 @@
+/*
+ * This file is part of the Buildings and Habitats object Model (BHoM)
+ * Copyright (c) 2015 - 2022, the respective contributors. All rights reserved.
+ *
+ * Each contributor holds copyright over their respective contributions.
+ * The project versioning (Git) records all such contribution source information.
+ *                                           
+ *                                                                              
+ * The BHoM is free software: you can redistribute it and/or modify         
+ * it under the terms of the GNU Lesser General Public License as published by  
+ * the Free Software Foundation, either version 3.0 of the License, or          
+ * (at your option) any later version.                                          
+ *                                                                              
+ * The BHoM is distributed in the hope that it will be useful,              
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of               
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                 
+ * GNU Lesser General Public License for more details.                          
+ *                                                                            
+ * You should have received a copy of the GNU Lesser General Public License     
+ * along with this code. If not, see <https://www.gnu.org/licenses/lgpl-3.0.html>.      
+ */
+
+using BH.oM.Geometry;
+using System;
+using System.ComponentModel;
+
+using BH.oM.Base.Attributes;
+using System.Collections.Generic;
+
+namespace BH.Engine.Geometry
+{
+    public static partial class Query
+    {
+        /***************************************************/
+        /**** Public Methods                            ****/
+        /***************************************************/
+
+        [Description("Return the list of face indices for an input face. The last face index (D) is not added if it's equal to -1.")]
+        [Input("meshFace", "Mesh face to query the indices for.")]
+        [Output("indices", "List of indices.")]
+        public static List<int> FaceIndices(this Face meshFace)
+        {
+            List<int> result = new List<int>() { meshFace.A, meshFace.B, meshFace.C };
+
+            if (meshFace.D != -1)
+                result.Add(meshFace.D);
+
+            return result;
+        }
+
+        /***************************************************/
+
+    }
+}
+
+