Add rate limiting for preview updates

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/AbstractMaterialGraphEditWindow.cs

 
         void Repaint();
 
-        void ToggleRequiresTime();
         void ToSubGraph();
 
         void Show();
         public abstract AbstractMaterialGraph GetMaterialGraph();
         public abstract void PingAsset();
         public abstract void UpdateAsset();
-        public abstract void ToggleRequiresTime();
         public abstract void ToSubGraph();
         public abstract Object selected { get; set; }
         public abstract void ChangeSelection(Object newSelection);
             graphEditorView.onUpdateAssetClick += UpdateAsset;
             graphEditorView.onConvertToSubgraphClick += ToSubGraph;
             graphEditorView.onShowInProjectClick += PingAsset;
-            graphEditorView.onTimeClick += ToggleRequiresTime;
             rootVisualContainer.Add(graphEditorView);
         }
 
             File.WriteAllText(path, EditorJsonUtility.ToJson(inMemoryAsset, true));
             shaderImporter.SaveAndReimport();
             AssetDatabase.ImportAsset(path);
-        }
-
-        public override void ToggleRequiresTime()
-        {
-            allowAlwaysRepaint = !allowAlwaysRepaint;
         }
 
         public override void ChangeSelection(Object newSelection)

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

 
         PreviewSystem m_PreviewSystem;
 
+        public PreviewRate previewRate
+        {
+            get { return m_PreviewSystem.previewRate; }
+            set { m_PreviewSystem.previewRate = value; }
+        }
+
         public MaterialGraphPresenter graphPresenter
         {
             get { return m_GraphPresenter; }

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/PreviewSystem.cs

         MaterialPropertyBlock m_PreviewPropertyBlock;
         MaterialGraphPreviewGenerator m_PreviewGenerator = new MaterialGraphPreviewGenerator();
         Texture2D m_ErrorTexture;
+        DateTime m_LastUpdate;
+
+        public PreviewRate previewRate { get; set; }
 
         public PreviewSystem(AbstractMaterialGraph graph)
         {
 
         public void Update()
         {
+            if (previewRate == PreviewRate.Off)
+                return;
+
+            var updateTime = DateTime.Now;
+            if (previewRate == PreviewRate.Throttled && (updateTime - m_LastUpdate) < TimeSpan.FromSeconds(1.0 / 10.0))
+                return;
+
+            m_LastUpdate = updateTime;
+
             PropagateNodeSet(m_DirtyShaders);
             foreach (var nodeGuid in m_DirtyShaders)
             {

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/Views/GraphEditorView.cs

         public Action onUpdateAssetClick { get; set; }
         public Action onConvertToSubgraphClick { get; set; }
         public Action onShowInProjectClick { get; set; }
-        public Action onTimeClick { get; set; }
 
         public GraphEditorView()
         {
                 m_ToolbarView.Add(new ToolbarSpaceView());
                 m_ToolbarView.Add(new ToolbarSeparatorView());
 
-                var timeButton = new ToolbarButtonView { text = "Time" };
-                timeButton.AddManipulator(new Clickable(() =>
+                m_TimeButton = new ToolbarButtonView { text = "" };
+                m_TimeButton.AddManipulator(new Clickable(() =>
-                    if (onTimeClick != null) onTimeClick();
+                    if (presenter == null)
+                        return;
+                    if (presenter.previewRate == PreviewRate.Full)
+                        presenter.previewRate = PreviewRate.Throttled;
+                    else if (presenter.previewRate == PreviewRate.Throttled)
+                        presenter.previewRate = PreviewRate.Off;
+                    else if (presenter.previewRate == PreviewRate.Off)
+                        presenter.previewRate = PreviewRate.Full;
+                    m_TimeButton.text = "Preview rate: " + presenter.previewRate;
-                m_ToolbarView.Add(timeButton);
+                m_ToolbarView.Add(m_TimeButton);
 
                 m_ToolbarView.Add(new ToolbarSeparatorView());
             }
         {
             m_GraphView.presenter = m_Presenter.graphPresenter;
             m_GraphInspectorView.presenter = m_Presenter.graphInspectorPresenter;
+            m_TimeButton.text = "Preview rate: " + presenter.previewRate;
+        ToolbarButtonView m_TimeButton;
 
         public GraphEditorPresenter presenter
         {
             onUpdateAssetClick = null;
             onConvertToSubgraphClick = null;
             onShowInProjectClick = null;
-            onTimeClick = null;
             if (m_GraphInspectorView != null) m_GraphInspectorView.Dispose();
         }
     }

MaterialGraphProject/ProjectSettings/ProjectVersion.txt

-m_EditorVersion: 2017.3.0b1
+m_EditorVersion: 2018.1.0a1

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/PreviewRate.cs

+namespace UnityEditor.MaterialGraph.Drawing
+{
+    public enum PreviewRate
+    {
+        Full,
+        Throttled,
+        Off
+    }
+}

MaterialGraphProject/Assets/UnityShaderEditor/Editor/Drawing/PreviewRate.cs.meta

+fileFormatVersion: 2
+guid: fa070520993a4b839e705dcd7f22e4d6
+timeCreated: 1506421104