Fix GPUEvent & SubGraph (#178)

* Fix SelectionHasCompleteSystems

Detect correctly if there are dependencies due to GPUEvent (or stripAttribute)

* Add allDependenciesIncludingNotCompilable in VFXData

This helper is usefull for UI + use it in SelectionHasCompleteSystems

* Add note without change the beahvior

* Remove debug ToArray()

Author: PaulDemeulenaere

com.unity.visualeffectgraph/CHANGELOG.md

@@ -15,6 +15,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Exclude Operator, Context, Block and Subgraph from Preset [Case 1232309](https://issuetracker.unity3d.com/product/unity/issues/guid/1232309/)
 - Fix [Case 1212002](https://fogbugz.unity3d.com/f/cases/1212002/)
 - Incorrect path on Linux while targetting Android, IOS or WebGL [Case 1279750](https://issuetracker.unity3d.com/product/unity/issues/guid/1279750/)
+- Prevent creation of subgraph containing only partial systems [Case 1284053](https://issuetracker.unity3d.com/product/unity/issues/guid/1284053/)
 
 ## [10.2.0] - 2020-10-19
 ### Added

com.unity.visualeffectgraph/Editor/Data/VFXData.cs

@@ -261,7 +261,7 @@ public void CollectAttributes()
             if (m_Contexts == null) // Context hasnt been initialized (may happen in unity tests but not during actual compilation)
                 InitImplicitContexts();
 
-            m_DependenciesIn = new HashSet<VFXData>(
+            var allDepenciesIn =
                 m_Contexts.Where(c => c.contextType == VFXContextType.Init)
                     .SelectMany(c => c.inputContexts.Where(i => i.contextType == VFXContextType.SpawnerGPU))
                     .SelectMany(c => c.allLinkedInputSlot)
@@ -281,18 +281,19 @@ public void CollectAttributes()
                         return false;
                     })
                     .Select(s => ((VFXModel)s.owner).GetFirstOfType<VFXContext>())
-                    .Where(c => c.CanBeCompiled())
-                    .Select(c => c.GetData())
-            );
+                    .Select(c => c.GetData());
 
-            m_DependenciesOut = new HashSet<VFXData>(
+            m_DependenciesIn = new HashSet<VFXData>(allDepenciesIn.Where(c => c.CanBeCompiled()));
+            m_DependenciesInNotCompilable = new HashSet<VFXData>(allDepenciesIn.Where(c => !c.CanBeCompiled()));
+
+            var allDependenciesOut =
                 owners.SelectMany(o => o.allLinkedOutputSlot)
                     .Select(s => (VFXContext)s.owner)
-                    .Where(c => c.CanBeCompiled())
                     .SelectMany(c => c.outputContexts)
-                    .Where(c => c.CanBeCompiled())
-                    .Select(c => c.GetData())
-            );
+                    .Select(c => c.GetData());
+
+            m_DependenciesOut = new HashSet<VFXData>(allDependenciesOut.Where(c => c.CanBeCompiled()));
+            m_DependenciesOutNotCompilable = new HashSet<VFXData>(allDependenciesOut.Where(c => !c.CanBeCompiled()));
 
             m_ContextsToAttributes.Clear();
             m_AttributesToContexts.Clear();
@@ -602,6 +603,7 @@ public uint layer
             }
         }
 
+        //Doesn't include not comilable context
         public IEnumerable<VFXData> dependenciesIn
         {
             get
@@ -618,6 +620,19 @@ public IEnumerable<VFXData> dependenciesOut
             }
         }
 
+        public IEnumerable<VFXData> allDependenciesIncludingNotCompilable
+        {
+            get
+            {
+                var all = Enumerable.Empty<VFXData>();
+                all = all.Concat(m_DependenciesIn);
+                all = all.Concat(m_DependenciesOut);
+                all = all.Concat(m_DependenciesInNotCompilable);
+                all = all.Concat(m_DependenciesOutNotCompilable);
+                return all;
+            }
+        }
+
         [SerializeField]
         protected List<VFXContext> m_Owners;
 
@@ -640,9 +655,15 @@ public IEnumerable<VFXData> dependenciesOut
         [NonSerialized]
         protected HashSet<VFXData> m_DependenciesIn = new HashSet<VFXData>();
 
+        [NonSerialized]
+        protected HashSet<VFXData> m_DependenciesInNotCompilable = new HashSet<VFXData>();
+
         [NonSerialized]
         protected HashSet<VFXData> m_DependenciesOut = new HashSet<VFXData>();
 
+        [NonSerialized]
+        protected HashSet<VFXData> m_DependenciesOutNotCompilable = new HashSet<VFXData>();
+
         [NonSerialized]
         protected uint m_Layer;
     }

com.unity.visualeffectgraph/Editor/GraphView/Views/VFXView.cs

@@ -2267,17 +2267,30 @@ void CollapseOperator(DropdownMenuAction a)
 
         public bool SelectionHasCompleteSystems()
         {
-            HashSet<VFXContextUI> selectedContexts = new HashSet<VFXContextUI>(selection.OfType<VFXContextUI>());
-            if (selectedContexts.Count() < 1)
+            HashSet<VFXContextUI> selectedContextUIs = new HashSet<VFXContextUI>(selection.OfType<VFXContextUI>());
+            if (selectedContextUIs.Count() < 1)
                 return false;
 
-            HashSet<VFXData> usedDatas = new HashSet<VFXData>(selectedContexts.Select(t => t.controller.model.GetData()).Where(t => t != null));
+            var relatedContext = selectedContextUIs.Select(t => t.controller.model);
 
+            //Adding manually VFXBasicGPUEvent, it doesn't appears as dependency.
+            var outputContextDataFromGPUEvent = relatedContext.OfType<VFXBasicGPUEvent>().SelectMany(o => o.outputContexts);
+            relatedContext = relatedContext.Concat(outputContextDataFromGPUEvent);
+            var selectedContextDatas = relatedContext.Select(o => o.GetData()).Where(o => o != null);
+
+            var selectedContextDependencies = selectedContextDatas.SelectMany(o => o.allDependenciesIncludingNotCompilable);
+            var allDatas = selectedContextDatas.Concat(selectedContextDependencies);
+
+            var allDatasHash = new HashSet<VFXData>(allDatas);
             foreach (var context in GetAllContexts())
             {
-                if (context.controller.model is VFXBlockSubgraphContext)
+                var model = context.controller.model;
+                if (model is VFXBlockSubgraphContext)
                     return false;
-                if (usedDatas.Contains(context.controller.model.GetData()) && !selectedContexts.Contains(context))
+
+                //We should exclude model.contextType == VFXContextType.Event of this condition.
+                //If VFXConvertSubgraph.TransferContextsFlowEdges has been fixed & renabled.
+                if (allDatasHash.Contains(model.GetData()) && !selectedContextUIs.Contains(context))
                     return false;
             }