Added an IF node

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/Presenters/IfNodePresenter.cs

+using System;
+using System.Collections.Generic;
+using RMGUI.GraphView;
+using UnityEditor.Graphing.Drawing;
+using UnityEngine;
+using UnityEngine.MaterialGraph;
+
+namespace UnityEditor.MaterialGraph.Drawing
+{
+    class IfControlPresenter : GraphControlPresenter
+    {
+        public override void OnGUIHandler()
+        {
+            base.OnGUIHandler();
+
+            var tNode = node as UnityEngine.MaterialGraph.IfNode;
+            if (tNode == null)
+                return;
+
+            tNode.ComparisonOperation = (IfNode.ComparisonOperationType)EditorGUILayout.EnumPopup(tNode.ComparisonOperation);
+        }
+
+        public override float GetHeight()
+        {
+            return (EditorGUIUtility.singleLineHeight + EditorGUIUtility.standardVerticalSpacing) + EditorGUIUtility.standardVerticalSpacing;
+        }
+    }
+
+    [Serializable]
+    public class IfNodePresenter : PropertyNodePresenter
+    {
+        protected override IEnumerable<GraphElementPresenter> GetControlData()
+        {
+            var instance = CreateInstance<IfControlPresenter>();
+            instance.Initialize(node);
+            return new List<GraphElementPresenter>(base.GetControlData()) { instance };
+        }
+    }
+}

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/Presenters/IfNodePresenter.cs.meta

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+timeCreated: 1495614828
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+  defaultReferences: []
+  executionOrder: 0
+  icon: {instanceID: 0}
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+  assetBundleName: 
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MaterialGraphProject/Assets/UnityShaderEditor/Runtime/Nodes/Logic.meta

+fileFormatVersion: 2
+guid: ccd4e915255073341a538223ae6838f8
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+timeCreated: 1495614357
+licenseType: Pro
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+  userData: 
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+  assetBundleVariant: 

MaterialGraphProject/Assets/UnityShaderEditor/Runtime/Nodes/Logic/IFNode.cs

+using UnityEngine.MaterialGraph;
+using UnityEngine.Graphing;
+
+namespace UnityEngine.MaterialGraph
+{
+    [Title("Logic/If")]
+    public class IfNode : Function4Input, IGeneratesFunction
+    {
+        public enum ComparisonOperationType
+        {
+            Equal = 0,
+            NotEqual,
+            GreaterThan,
+            GreaterThanOfEqual,
+            LessThan,
+            LessThanOfEqual
+        }
+
+        [SerializeField]
+        private ComparisonOperationType m_comparisonOperation = ComparisonOperationType.Equal;
+
+        public ComparisonOperationType ComparisonOperation
+        {
+            get { return m_comparisonOperation; }
+            set
+            {
+                if (m_comparisonOperation == value)
+                    return;
+
+                m_comparisonOperation = value;
+                if (onModified != null)
+                {
+                    onModified(this, ModificationScope.Graph);
+                }
+            }
+        }
+
+        public IfNode()
+        {
+            name = "If";
+        }
+
+        protected override string GetFunctionName()
+        {
+            return "unity_if_" + precision;
+        }
+
+        protected override string GetInputSlot1Name()
+        {
+            return "A";
+        }
+
+        protected override string GetInputSlot2Name()
+        {
+            return "B";
+        }
+
+        protected override string GetInputSlot3Name()
+        {
+            return "True Value";
+        }
+
+        protected override string GetInputSlot4Name()
+        {
+            return "False Value";
+        }
+
+        protected override MaterialSlot GetInputSlot1()
+        {
+            return new MaterialSlot(InputSlot1Id, GetInputSlot1Name(), kInputSlot1ShaderName, UnityEngine.Graphing.SlotType.Input, SlotValueType.Dynamic, Vector4.zero);
+        }
+
+        protected override MaterialSlot GetInputSlot2()
+        {
+            return new MaterialSlot(InputSlot2Id, GetInputSlot2Name(), kInputSlot2ShaderName, UnityEngine.Graphing.SlotType.Input, SlotValueType.Dynamic, Vector4.zero);
+        }
+
+        protected override MaterialSlot GetInputSlot3()
+        {
+            return new MaterialSlot(InputSlot3Id, GetInputSlot3Name(), kInputSlot3ShaderName, UnityEngine.Graphing.SlotType.Input, SlotValueType.Dynamic, Vector4.zero);
+        }
+
+        protected override MaterialSlot GetOutputSlot()
+        {
+            return new MaterialSlot(OutputSlotId, GetOutputSlotName(), kOutputSlotShaderName, UnityEngine.Graphing.SlotType.Output, SlotValueType.Dynamic, Vector4.zero);
+        }
+
+        public void GenerateNodeFunction(ShaderGenerator visitor, GenerationMode generationMode)
+        {
+            var outputString = new ShaderGenerator();
+            outputString.AddShaderChunk(GetFunctionPrototype("a", "b", "trueOutputValue", "falseOutputValue"), false);
+            outputString.AddShaderChunk("{", false);
+            outputString.Indent();
+
+
+            if (m_comparisonOperation == ComparisonOperationType.Equal)
+            {
+                outputString.AddShaderChunk("if (a == b)", false);
+            }
+            else if (m_comparisonOperation == ComparisonOperationType.NotEqual)
+            {
+                outputString.AddShaderChunk("if (a != b)", false);
+            }
+            else if (m_comparisonOperation == ComparisonOperationType.GreaterThan)
+            {
+                outputString.AddShaderChunk("if (a > b)", false);
+            }
+            else if (m_comparisonOperation == ComparisonOperationType.GreaterThanOfEqual)
+            {
+                outputString.AddShaderChunk("if (a >= b)", false);
+            }
+            else if (m_comparisonOperation == ComparisonOperationType.LessThan)
+            {
+                outputString.AddShaderChunk("if (a < b)", false);
+            }
+            else if (m_comparisonOperation == ComparisonOperationType.LessThanOfEqual)
+            {
+                outputString.AddShaderChunk("if (a <= b)", false);
+            }
+
+            outputString.AddShaderChunk("{", false);
+            outputString.Indent();
+            outputString.AddShaderChunk("return trueOutputValue;", false);
+            outputString.Deindent();
+            outputString.AddShaderChunk("}", false);
+            outputString.AddShaderChunk("else", false);
+            outputString.AddShaderChunk("{", false);
+            outputString.Indent();
+            outputString.AddShaderChunk("return falseOutputValue;", false);
+            outputString.Deindent();
+            outputString.AddShaderChunk("}", false);
+
+
+            outputString.Deindent();
+            outputString.AddShaderChunk("}", false);
+
+            visitor.AddShaderChunk(outputString.GetShaderString(0), true);
+        }
+    }
+}

MaterialGraphProject/Assets/UnityShaderEditor/Runtime/Nodes/Logic/IFNode.cs.meta

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