diff --git a/src/lib/StdAdaptors.h b/src/lib/StdAdaptors.h
index f6d1439f9..d4f0803ae 100644
--- a/src/lib/StdAdaptors.h
+++ b/src/lib/StdAdaptors.h
@@ -426,6 +426,9 @@ struct StdArrayDefaultArrayAdapt
 template <class T, class D>
 inline StdArrayDefaultArrayAdapt<T, D> mkArrayAdaptDefArr(T *pArray, size_t iSize, const D &rDefault) { return StdArrayDefaultArrayAdapt<T, D>(pArray, iSize, rDefault); }
 #define mkArrayAdaptDMA(A, D) mkArrayAdaptDefArr(A, sizeof(A) / sizeof(*(A)), D)
+template <class T, class D, class M>
+inline StdArrayDefaultArrayAdapt<T, D, M> mkArrayAdaptDefArrMap(T *pArray, size_t iSize, const D &rDefault, const M &map) { return StdArrayDefaultArrayAdapt<T, D, M>(pArray, iSize, rDefault, map); }
+#define mkArrayAdaptDMAM(A, D, M) mkArrayAdaptDefArrMap(A, sizeof(A) / sizeof(*(A)), D, M)
 
 // * Insertion Adaptor
 // Compile a value before / after another
@@ -934,12 +937,14 @@ struct StdBitfieldAdapt
 		// writing?
 		if (!pComp->isCompiler())
 		{
-			T val = rVal;
+			T val = rVal, orig_val = rVal;
 			// Write until value is comsumed
 			bool fFirst = true;
-			for (const Entry *pName = pNames; val && pName->Name; pName++)
+			for (const Entry *pName = pNames; pName->Name; pName++)
 				if ((pName->Val & val) == pName->Val)
 				{
+					// Avoid writing meaningless none-values (e.g. Category=C4D_None|C4D_Object)
+					if (orig_val && !pName->Val) continue;
 					// Put "|"
 					if (!fFirst) pComp->Separator(StdCompiler::SEP_VLINE);
 					// Put name
diff --git a/src/object/C4Shape.cpp b/src/object/C4Shape.cpp
index c9a93351b..c31f2bfe1 100644
--- a/src/object/C4Shape.cpp
+++ b/src/object/C4Shape.cpp
@@ -528,6 +528,21 @@ void C4Shape::CreateOwnOriginalCopy(C4Shape &rFrom)
 
 void C4Shape::CompileFunc(StdCompiler *pComp, const C4Shape *default_shape)
 {
+	const StdBitfieldEntry<int32_t> ContactDirections[] =
+	{
+
+		{ "CNAT_None", CNAT_None },
+		{ "CNAT_Left", CNAT_Left },
+		{ "CNAT_Right", CNAT_Right },
+		{ "CNAT_Top", CNAT_Top },
+		{ "CNAT_Bottom", CNAT_Bottom },
+		{ "CNAT_Center", CNAT_Center },
+		{ "CNAT_MultiAttach", CNAT_MultiAttach },
+		{ "CNAT_NoCollision", CNAT_NoCollision },
+
+		{ NULL, 0 }
+	};
+
 	// a default shape is given in object compilation context only
 	bool fRuntime = !!default_shape;
 	C4Shape default_def_shape;
@@ -540,7 +555,7 @@ void C4Shape::CompileFunc(StdCompiler *pComp, const C4Shape *default_shape)
 	pComp->Value(mkNamingAdapt( VtxNum,                                                   "Vertices",           default_shape->VtxNum));
 	pComp->Value(mkNamingAdapt( mkArrayAdaptDMA(VtxX, default_shape->VtxX),               "VertexX",            default_shape->VtxX));
 	pComp->Value(mkNamingAdapt( mkArrayAdaptDMA(VtxY, default_shape->VtxY),               "VertexY",            default_shape->VtxY));
-	pComp->Value(mkNamingAdapt( mkArrayAdaptDMA(VtxCNAT, default_shape->VtxCNAT),         "VertexCNAT",         default_shape->VtxCNAT));
+	pComp->Value(mkNamingAdapt( mkArrayAdaptDMAM(VtxCNAT, default_shape->VtxCNAT, [&](decltype(*VtxCNAT) &elem){ return mkBitfieldAdapt<int32_t>(elem, ContactDirections); }), "VertexCNAT", default_shape->VtxCNAT));
 	pComp->Value(mkNamingAdapt( mkArrayAdaptDMA(VtxFriction, default_shape->VtxFriction), "VertexFriction",     default_shape->VtxFriction));
 	pComp->Value(mkNamingAdapt( ContactDensity,             "ContactDensity",     default_shape->ContactDensity));
 	pComp->Value(mkNamingAdapt( FireTop,                    "FireTop",            default_shape->FireTop));