Seed legacy type-level material relation GlobalIds from material identity

CHANGELOG.md

@@ -6,6 +6,10 @@ API between minor releases.
 
 ## [Unreleased]
 
+### Breaking changes
+
+- Legacy IFC profile: the `GlobalId` of a type-level `IfcRelAssociatesMaterial` relation is now seeded from the material element id list (`type-materials:{materialIds}`, as `materials:{materialIds}` already is for product-level relations, and `type-layer-set:{seed}` from the host type id or layer-set group key) instead of the STEP entity number of the relating material, material list or layer set. Type-level material relation `GlobalId`s in the legacy profile change once and no longer shift when entities are added or removed earlier in the file; product-level material relations and the current IFC profile are unchanged. (Closes #88)
+
 ### Added
 
 - Default output, current IFC profile: every beam with a straight drive curve gets `Pset_BeamCommon.Slope`, the angle in degrees of its drive curve to the horizontal (0 for a horizontal beam, never negative), whether or not BaseQuantities are exported and whatever its body; its quantities are unchanged. A beam without a straight drive curve gets no Slope.

src/RvtIO/Ifc/IfcExporter.cs

@@ -5834,7 +5834,7 @@ int EnsureUnnamedMaterial() =>
         }
 
         var layerSetByKey = new Dictionary<string, (int LayerSetId, double TotalThicknessMm)>();
-        var layerSetByProductEntity = new Dictionary<int, int>();
+        var layerSetByProductEntity = new Dictionary<int, (int EntityId, string Seed)>();
         var layerUsageProductEntities = new HashSet<int>();
         var layeredProducts = exportedIfcElements
             .Select(pair => (ElementId: pair.Key, Product: pair.Value,
@@ -5913,7 +5913,9 @@ int EnsureUnnamedMaterial() =>
                 layerSetByKey[layerSetKey] = layerSet;
             }
 
-            foreach (var item in group) layerSetByProductEntity[item.Product.entityId] = layerSet.LayerSetId;
+            string layerSetSeed = first.Native is { } nativeSeed
+                ? nativeSeed.TypeId.ToString(CultureInfo.InvariantCulture) : group.Key;
+            foreach (var item in group) layerSetByProductEntity[item.Product.entityId] = (layerSet.LayerSetId, layerSetSeed);
             var associated = CurrentProfile ? group.Where(item => item.Product.ifcType != "IFCWALL").ToList() : group.ToList();
             if (associated.Count == 0) continue;
 
@@ -6152,7 +6154,7 @@ int EnsureUnnamedMaterial() =>
             for (int part = 0; part < (partMaterials?.Count ?? 1); part++)
             {
                 var partIds = partMaterials == null ? materialElementIds : [partMaterials[part]];
-                string materialKey = string.Join(',', partIds);
+                string materialKey = string.Join(',', partIds.Select(id => id.ToString(CultureInfo.InvariantCulture)));
                 if (!directMaterialProducts.TryGetValue(materialKey, out var association))
                     association = (partIds, new List<int>());
                 if (pieceBased && product.ifcType == "IFCSLAB" && element.CategoryId == -2001300)
@@ -6166,7 +6168,7 @@ int EnsureUnnamedMaterial() =>
             }
         }
 
-        var relatingMaterialByProductEntity = new Dictionary<int, int>();
+        var relatingMaterialByProductEntity = new Dictionary<int, (int EntityId, string Seed)>();
         var directRelationByRelating = new Dictionary<int, (int Index, string GuidArg, List<int> Products)>();
         foreach (var (materialKey, association) in directMaterialProducts)
         {
@@ -6177,9 +6179,9 @@ int EnsureUnnamedMaterial() =>
                 ? materialIds[0]
                 : w.Add("IFCMATERIALLIST", StepWriter.List(materialIds.Select(R)));
             foreach (int productEntityId in association.ProductIds)
-                relatingMaterialByProductEntity[productEntityId] = relatingMaterialId;
+                relatingMaterialByProductEntity[productEntityId] = (relatingMaterialId, materialKey);
             foreach (int productEntityId in typeOnlyMaterialProducts.GetValueOrDefault(materialKey) ?? [])
-                relatingMaterialByProductEntity[productEntityId] = relatingMaterialId;
+                relatingMaterialByProductEntity[productEntityId] = (relatingMaterialId, materialKey);
             if (association.ProductIds.Count > 0)
             {
                 string guidArg = S(IfcGuid.FromName($"materials:{materialKey}"));
@@ -67077,7 +67079,7 @@ internal static (string? Full, string? Own) TypeObjectNameParts(Element typeElem
     /// </summary>
     private static void AssociateTypeObjectMaterials(
         StepWriter w, int ownerHistId, int startIndex,
-        IReadOnlyDictionary<int, int> relatingMaterialByProductEntity, HostLayerSets? layerSets = null,
+        IReadOnlyDictionary<int, (int EntityId, string Seed)> relatingMaterialByProductEntity, HostLayerSets? layerSets = null,
         IReadOnlyDictionary<int, (int Index, string GuidArg, List<int> Products)>? directRelations = null)
     {
         var typeClassByEntity = new Dictionary<int, string>();
@@ -67096,8 +67098,8 @@ private static void AssociateTypeObjectMaterials(
             firstMemberByType.Add((typeEntityId, firstMember));
         }
 
-        var typesByRelatingMaterial = new SortedDictionary<int, List<int>>();
-        var typesByLayerSet = new SortedDictionary<int, List<int>>();
+        var typesByRelatingMaterial = new SortedDictionary<int, (string Seed, List<int> Types)>();
+        var typesByLayerSet = new SortedDictionary<int, (string Seed, List<int> Types)>();
         foreach (var (typeEntityId, firstMember) in firstMemberByType)
         {
             if (layerSets != null && typeClassByEntity.GetValueOrDefault(typeEntityId) == "IFCSTAIRFLIGHTTYPE") continue;
@@ -67106,10 +67108,11 @@ private static void AssociateTypeObjectMaterials(
             // usage (the host-object export with the type handle); ceilings and roofs do not.
             if (layerSets != null && typeClassByEntity.GetValueOrDefault(typeEntityId) is { } hostTypeClass
                 && (hostTypeClass == "IFCWALLTYPE" || hostTypeClass == "IFCSLABTYPE" && layerSets.UsageProducts.Contains(firstMember))
-                && layerSets.ByProduct.TryGetValue(firstMember, out int typeLayerSet))
+                && layerSets.ByProduct.TryGetValue(firstMember, out var typeLayerSet))
             {
-                if (!typesByLayerSet.TryGetValue(typeLayerSet, out var typed)) typesByLayerSet[typeLayerSet] = typed = new List<int>();
-                typed.Add(typeEntityId);
+                if (!typesByLayerSet.TryGetValue(typeLayerSet.EntityId, out var typed))
+                    typesByLayerSet[typeLayerSet.EntityId] = typed = (typeLayerSet.Seed, new List<int>());
+                typed.Types.Add(typeEntityId);
                 continue;
             }
             // Host objects (walls, floors, ceilings, roofs) give their type the layer set instead.
@@ -67119,13 +67122,13 @@ private static void AssociateTypeObjectMaterials(
             bool hostType = hostOrFamilyTypeClass is null or "IFCCURTAINWALLTYPE" or "IFCWALLTYPE"
                 or "IFCSLABTYPE" or "IFCCOVERINGTYPE" or "IFCROOFTYPE";
             if (hostType && !slabFamilyType
-                || !relatingMaterialByProductEntity.TryGetValue(firstMember, out int relatingMaterial))
+                || !relatingMaterialByProductEntity.TryGetValue(firstMember, out var relatingMaterial))
                 continue;
-            if (!typesByRelatingMaterial.TryGetValue(relatingMaterial, out var types))
-                typesByRelatingMaterial[relatingMaterial] = types = new List<int>();
-            types.Add(typeEntityId);
+            if (!typesByRelatingMaterial.TryGetValue(relatingMaterial.EntityId, out var types))
+                typesByRelatingMaterial[relatingMaterial.EntityId] = types = (relatingMaterial.Seed, new List<int>());
+            types.Types.Add(typeEntityId);
         }
-        foreach (var (relatingMaterial, typeEntityIds) in typesByRelatingMaterial)
+        foreach (var (relatingMaterial, (materialSeed, typeEntityIds)) in typesByRelatingMaterial)
         {
             if (directRelations != null && directRelations.TryGetValue(relatingMaterial, out var direct))
             {
@@ -67134,12 +67137,12 @@ private static void AssociateTypeObjectMaterials(
                 continue;
             }
             w.Add("IFCRELASSOCIATESMATERIAL",
-                $"{S(IfcGuid.FromName($"type-materials:{relatingMaterial}"))},{R(ownerHistId)},$,$,"
+                $"{S(IfcGuid.FromName($"type-materials:{materialSeed}"))},{R(ownerHistId)},$,$,"
                 + $"{StepWriter.List(typeEntityIds.Select(R))},{R(relatingMaterial)}");
         }
-        foreach (var (layerSet, typeEntityIds) in typesByLayerSet)
+        foreach (var (layerSet, (layerSetSeed, typeEntityIds)) in typesByLayerSet)
             w.Add("IFCRELASSOCIATESMATERIAL",
-                $"{S(IfcGuid.FromName($"type-layer-set:{layerSet}"))},{R(ownerHistId)},$,$,"
+                $"{S(IfcGuid.FromName($"type-layer-set:{layerSetSeed}"))},{R(ownerHistId)},$,$,"
                 + $"{StepWriter.List(typeEntityIds.Select(R))},{R(layerSet)}");
     }
 
@@ -67186,8 +67189,8 @@ private static int WriteInsulationCoverings(
     /// The layer sets of the host objects of one export: by product entity, and which products got
     /// a usage.
     /// </summary>
-    private sealed record HostLayerSets(IReadOnlyDictionary<int, int> ByProduct, IReadOnlySet<int> UsageProducts,
-        IReadOnlySet<int> TypeOnlyProducts);
+    private sealed record HostLayerSets(IReadOnlyDictionary<int, (int EntityId, string Seed)> ByProduct,
+        IReadOnlySet<int> UsageProducts, IReadOnlySet<int> TypeOnlyProducts);
 
     /// <summary>
     /// The connector export creates a distribution port for every unconnected connector of an MEP

tests/RvtIO.Tests/IfcExporterTypeObjectsTests.cs

@@ -523,8 +523,126 @@ public void ComponentType_ReceivesTheMaterialOfItsFirstInstance()
             .Select(id => EntityArgs(ifc, id, "IFCRELASSOCIATESMATERIAL")).ToList();
         Assert.Equal(2, relations.Count);
         Assert.All(relations, args => Assert.Equal($"#{material}", args[5]));
-        Assert.Contains(relations, args => args[4] == $"(#{memberEntity})");
-        Assert.Contains(relations, args => args[4] == $"(#{typeEntity})");
+        var productRel = Assert.Single(relations, args => args[4] == $"(#{memberEntity})");
+        var typeRel = Assert.Single(relations, args => args[4] == $"(#{typeEntity})");
+        Assert.Equal($"'{IfcGuid.FromName("materials:0")}'", productRel[0]);
+        Assert.Equal($"'{IfcGuid.FromName("type-materials:0")}'", typeRel[0]);
+    }
+
+    [Fact]
+    public void LegacyTypeMaterialRelationGlobalIds_StayStableWhenEarlierStepEntitiesShift()
+    {
+        Element MaterialElement(int id, string name) => new()
+        {
+            Id = id,
+            TypeId = -1,
+            IsBlockOnly = true,
+            CategoryId = -2000700,
+            Category = "OST_Materials",
+            Name = name,
+            HasShadingAppearance = true,
+            Parameters =
+            [
+                new Parameter { Id = id + 1, Definition = new Definition { Name = "MATERIAL_PARAM_COLOR" }, Value = 0x112233, StorageType = StorageType.Integer },
+                new Parameter { Id = id + 2, Definition = new Definition { Name = "MATERIAL_PARAM_SHININESS" }, Value = 25, StorageType = StorageType.Integer },
+            ],
+        };
+
+        Element[] BuildBaseElements()
+        {
+            var steel = MaterialElement(700, "Steel");
+            var glass = MaterialElement(710, "Glass");
+            var wood = MaterialElement(720, "Wood");
+
+            var singleType = TypeElement(500, "SingleType", "MullionFamily");
+            singleType.CategoryId = -2000171;
+            singleType.Parameters.Add(new Parameter { Id = -1002107, StorageType = StorageType.ElementId, Value = 700 });
+            var singleMullion = Product(100, -2000171, "Mullion", 500, 500, centreX: 0);
+            singleMullion.TypeId = 500;
+            foreach (var face in singleMullion.Geometry!.Faces)
+                face.RenderStyleId = 700;
+
+            var multiType = TypeElement(510, "MultiType", "DoorFamily");
+            multiType.CategoryId = DoorCategoryId;
+            var door = Product(110, DoorCategoryId, "Doors", 510, 510, centreX: 10);
+            door.TypeId = 510;
+            door.Geometry!.Faces[0].RenderStyleId = 710;
+            door.Geometry.Faces[1].RenderStyleId = 720;
+            for (int i = 2; i < door.Geometry.Faces.Count; i++)
+                door.Geometry.Faces[i].RenderStyleId = 710;
+
+            var hostWall = Product(999, WallCategoryId, "Walls", elemTypeParamId: null, nativeMasterSymbolId: null, centreX: 20);
+            return [steel, glass, wood, hostWall, singleType, singleMullion, multiType, door];
+        }
+
+        string baselineIfc = ExportToText(IfcProfile.Legacy, BuildBaseElements());
+
+        // Prepend extra elements and custom properties so STEP entity numbers of materials,
+        // material lists, products and types all shift significantly.
+        var extraColumnType = TypeElement(400, "ExtraColType", "ExtraFamily");
+        extraColumnType.CategoryId = -2001330;
+        var extraColumn = Product(50, -2001330, "Structural Columns", 400, 400, centreX: -20);
+        for (int p = 0; p < 12; p++)
+        {
+            extraColumn.Parameters.Add(new Parameter
+            {
+                Id = 800000 + p,
+                Definition = new Definition { Id = 800000 + p, Name = $"SpanExtra_{p}" },
+                StorageType = StorageType.Double,
+                Value = 10.0 + p,
+            });
+        }
+        string shiftedIfc = ExportToText(IfcProfile.Legacy, [extraColumnType, extraColumn, .. BuildBaseElements()]);
+
+        // Verify the relating IFCMATERIAL and IFCMATERIALLIST STEP numbers actually shifted.
+        int baseSteelEntity = EntityIds(baselineIfc, "IFCMATERIAL")
+            .Single(id => EntityArgs(baselineIfc, id, "IFCMATERIAL")[0] == "'Steel'");
+        int shiftedSteelEntity = EntityIds(shiftedIfc, "IFCMATERIAL")
+            .Single(id => EntityArgs(shiftedIfc, id, "IFCMATERIAL")[0] == "'Steel'");
+        Assert.NotEqual(baseSteelEntity, shiftedSteelEntity);
+
+        int baseMatList = SoleEntityId(baselineIfc, "IFCMATERIALLIST");
+        int shiftedMatList = SoleEntityId(shiftedIfc, "IFCMATERIALLIST");
+        Assert.NotEqual(baseMatList, shiftedMatList);
+
+        string expectedSingleProductGuid = $"'{IfcGuid.FromName("materials:700")}'";
+        string expectedSingleTypeGuid = $"'{IfcGuid.FromName("type-materials:700")}'";
+        string expectedMultiProductGuid = $"'{IfcGuid.FromName("materials:710,720")}'";
+        string expectedMultiTypeGuid = $"'{IfcGuid.FromName("type-materials:710,720")}'";
+
+        foreach ((string ifc, int steelEntity, int matListEntity) in new[]
+        {
+            (baselineIfc, baseSteelEntity, baseMatList),
+            (shiftedIfc, shiftedSteelEntity, shiftedMatList),
+        })
+        {
+            var rels = EntityIds(ifc, "IFCRELASSOCIATESMATERIAL")
+                .Select(id => EntityArgs(ifc, id, "IFCRELASSOCIATESMATERIAL")).ToList();
+            int memberTypeEntity = SoleEntityId(ifc, "IFCMEMBERTYPE");
+            int doorStyleEntity = SoleEntityId(ifc, "IFCDOORSTYLE");
+
+            var singleTypeRel = Assert.Single(rels, a => a[4] == $"(#{memberTypeEntity})" && a[5] == $"#{steelEntity}");
+            Assert.Equal(expectedSingleTypeGuid, singleTypeRel[0]);
+
+            var multiTypeRel = Assert.Single(rels, a => a[4] == $"(#{doorStyleEntity})" && a[5] == $"#{matListEntity}");
+            Assert.Equal(expectedMultiTypeGuid, multiTypeRel[0]);
+
+            Assert.Contains(rels, a => a[0] == expectedSingleProductGuid && a[5] == $"#{steelEntity}");
+            Assert.Contains(rels, a => a[0] == expectedMultiProductGuid && a[5] == $"#{matListEntity}");
+        }
+
+        // Current profile keeps its existing MD5("{project GlobalId}IfcRelAssociatesMaterial:{first related GlobalId}") seed.
+        string currentIfc = ExportToText(IfcProfile.Current, BuildBaseElements());
+        int projectEntity = SoleEntityId(currentIfc, "IFCPROJECT");
+        string projectGuid = EntityArgs(currentIfc, projectEntity, "IFCPROJECT")[0].Trim('\'');
+        int currentMemberType = SoleEntityId(currentIfc, "IFCMEMBERTYPE");
+        string currentMemberTypeGuid = EntityArgs(currentIfc, currentMemberType, "IFCMEMBERTYPE")[0].Trim('\'');
+        var currentRels = EntityIds(currentIfc, "IFCRELASSOCIATESMATERIAL")
+            .Select(id => EntityArgs(currentIfc, id, "IFCRELASSOCIATESMATERIAL")).ToList();
+        var mergedSteelRel = Assert.Single(currentRels, a => a[4].Contains($"#{currentMemberType}"));
+        Assert.Equal(
+            $"'{IfcGuid.FromMd5($"{projectGuid}IfcRelAssociatesMaterial:{currentMemberTypeGuid}")}'",
+            mergedSteelRel[0]);
     }
 
     [Theory]