Override GradientShaderProperty declaration for preview rendering

com.unity.shadergraph/Editor/Data/Graphs/GradientShaderProperty.cs

                 alphas[i] = GetAlphaKey(i, gradient.alphaKeys[i].alpha, gradient.alphaKeys[i].time);
 
             s.AppendLine("Gradient g;");
-            s.AppendLine("g.type = 0;");
+            s.AppendLine("g.type = {0};",
+                (int)gradient.mode);
             s.AppendLine("g.colorsLength = {0};",
                 gradient.colorKeys.Length);
             s.AppendLine("g.alphasLength = {0};",
 
         public static bool CheckEquivalency(Gradient A, Gradient B)
         {
+            var currentMode = A.mode;
+            var newMode = B.mode;
-            if (currentColorKeys.Length != newColorKeys.Length || currentAlphaKeys.Length != newAlphaKeys.Length)
+            if (currentMode != newMode || currentColorKeys.Length != newColorKeys.Length || currentAlphaKeys.Length != newAlphaKeys.Length)
             {
                 return false;
             }
             value = new Gradient();
         }
 
+        private bool m_OverrideMembers = false;
+
+        private string m_OverrideSlotName;
+
         public override PropertyType propertyType
         {
             get { return PropertyType.Gradient; }
         {
             return string.Empty;
         }
+
+        public void OverrideMembers(string slotName)
+        {
+            m_OverrideMembers = true;
+            m_OverrideSlotName = slotName;
+        }
-            ShaderStringBuilder s = new ShaderStringBuilder();
-            s.AppendLine("Gradient Unity{0} ()", referenceName);
-            using (s.BlockScope())
+            if(m_OverrideMembers)
+            {
+                ShaderStringBuilder s = new ShaderStringBuilder();
+                s.AppendLine("Gradient Unity{0} ()",
+                referenceName);
+                using (s.BlockScope())
+                {
+                    s.AppendLine("Gradient g;");
+                    s.AppendLine("g.type = {0}_Type;", m_OverrideSlotName);
+                    s.AppendLine("g.colorsLength = {0}_ColorsLength;", m_OverrideSlotName);
+                    s.AppendLine("g.alphasLength = {0}_AlphasLength;", m_OverrideSlotName);
+                    for(int i = 0; i < 8; i++)
+                    {
+                        s.AppendLine("g.colors[{0}] = {1}_ColorKey{0};", i, m_OverrideSlotName);
+                    }
+                    for(int i = 0; i < 8; i++)
+                    {
+                        s.AppendLine("g.alphas[{0}] = {1}_AlphaKey{0};", i, m_OverrideSlotName);
+                    }
+                    s.AppendLine("return g;", true);
+                }
+                return s.ToString();
+            }
+            else
-                GradientUtils.GetGradientDeclaration(value, ref s);
-                s.AppendLine("return g;", true);
+                ShaderStringBuilder s = new ShaderStringBuilder();
+                s.AppendLine("Gradient Unity{0} ()", referenceName);
+                using (s.BlockScope())
+                {
+                    GradientUtils.GetGradientDeclaration(value, ref s);
+                    s.AppendLine("return g;", true);
+                }
+                return s.ToString();
-            return s.ToString();
         }
 
         public override PreviewProperty GetPreviewMaterialProperty()

com.unity.shadergraph/Editor/Data/Nodes/Input/Gradient/GradientAssetNode.cs

                     var newAlphaKeys = value.alphaKeys;
 
                     m_Gradient.SetKeys(newColorKeys, newAlphaKeys);
+                    m_Gradient.mode = value.mode;
                     Dirty(ModificationScope.Node);
                 }
             }
             properties.Add(new PreviewProperty(PropertyType.Vector1)
             {
                 name = string.Format("_{0}_Type", GetVariableNameForNode()),
-                floatValue = 0
+                floatValue = (int)m_Gradient.mode
             });
 
             properties.Add(new PreviewProperty(PropertyType.Vector1)