Add LegacyAttribute for declaring old class names directly on the node class

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Graphs/AbstractMaterialGraph.cs

 using System.Collections.Generic;
 using System.Linq;
 using System.Text.RegularExpressions;
+using UnityEditor.Compilation;
 using UnityEngine;
 using UnityEditor.Graphing;
 using UnityEditor.Graphing.Util;
         Dictionary<SerializationHelper.TypeSerializationInfo, SerializationHelper.TypeSerializationInfo> GetLegacyTypeRemapping()
         {
             var result = new Dictionary<SerializationHelper.TypeSerializationInfo, SerializationHelper.TypeSerializationInfo>();
-            var viewNode = new SerializationHelper.TypeSerializationInfo
-            {
-                fullName = "UnityEngine.MaterialGraph.ViewDirectionNode"
-            };
-            result[viewNode] = SerializationHelper.GetTypeSerializableAsString(typeof(ViewDirectionNode));
-
-            var normalNode = new SerializationHelper.TypeSerializationInfo
-            {
-                fullName = "UnityEngine.MaterialGraph.NormalNode"
-            };
-            result[normalNode] = SerializationHelper.GetTypeSerializableAsString(typeof(NormalVectorNode));
-
-            var worldPosNode = new SerializationHelper.TypeSerializationInfo
-            {
-                fullName = "UnityEngine.MaterialGraph.WorldPosNode"
-            };
-            result[worldPosNode] = SerializationHelper.GetTypeSerializableAsString(typeof(PositionNode));
-
-            var sampleTexture2DNode = new SerializationHelper.TypeSerializationInfo
+            foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
-                fullName = "UnityEditor.ShaderGraph.Texture2DNode"
-            };
-            result[sampleTexture2DNode] = SerializationHelper.GetTypeSerializableAsString(typeof(SampleTexture2DNode));
+                foreach (var type in assembly.GetTypes())
+                {
+                    if (type.IsAbstract)
+                        continue;
+                    foreach (var attribute in type.GetCustomAttributes(typeof(LegacyAttribute), false))
+                    {
+                        var legacyAttribute = (LegacyAttribute)attribute;
+                        var serializationInfo = new SerializationHelper.TypeSerializationInfo { fullName = legacyAttribute.fullName };
+                        result[serializationInfo] = SerializationHelper.GetTypeSerializableAsString(type);
+                    }
-            var sampleCubemapNode = new SerializationHelper.TypeSerializationInfo
-            {
-                fullName = "UnityEditor.ShaderGraph.CubemapNode"
-            };
-            result[sampleCubemapNode] = SerializationHelper.GetTypeSerializableAsString(typeof(SampleCubemapNode));
+                }
+            }
 
             return result;
         }

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Nodes/Input/Geometry/NormalVectorNode.cs

 
 namespace UnityEditor.ShaderGraph
 {
+    [Legacy("UnityEngine.MaterialGraph.NormalNode")]
     [Title("Input", "Geometry", "Normal Vector")]
     public class NormalVectorNode : GeometryNode, IMayRequireNormal
     {

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Nodes/Input/Geometry/PositionNode.cs

 
 namespace UnityEditor.ShaderGraph
 {
+    [Legacy("UnityEngine.MaterialGraph.WorldPosNode")]
     [Title("Input", "Geometry", "Position")]
     public class PositionNode : GeometryNode, IMayRequirePosition
     {

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Nodes/Input/Geometry/ViewDirectionNode.cs

 
 namespace UnityEditor.ShaderGraph
 {
+    [Legacy("UnityEngine.MaterialGraph.ViewDirectionNode")]
     [Title("Input", "Geometry", "View Direction")]
     public class ViewDirectionNode : GeometryNode, IMayRequireViewDirection
     {

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Nodes/Input/Texture/SampleCubemapNode.cs

 
 namespace UnityEditor.ShaderGraph
 {
+    [Legacy("UnityEditor.ShaderGraph.CubemapNode")]
     [Title("Input", "Texture", "Sample Cubemap")]
     public class SampleCubemapNode : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireViewDirection, IMayRequireNormal
     {

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Nodes/Input/Texture/SampleTexture2DNode.cs

         Normal
     };
 
+    [Legacy("UnityEditor.ShaderGraph.Texture2DNode")]
     [Title("Input", "Texture", "Sample Texture 2D")]
     public class SampleTexture2DNode : AbstractMaterialNode, IGeneratesBodyCode, IMayRequireMeshUV
     {

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Nodes/LegacyAttribute.cs

+using System;
+
+namespace UnityEditor.ShaderGraph
+{
+    [AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
+    public class LegacyAttribute : Attribute
+    {
+        public string fullName { get; private set; }
+
+        public LegacyAttribute(string fullName)
+        {
+            this.fullName = fullName;
+        }
+    }
+}

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Data/Nodes/LegacyAttribute.cs.meta

+fileFormatVersion: 2
+guid: ae5b0289aecc42c2b6f5b5b08b80bdd9
+timeCreated: 1513592955