fix: incorrect handling of shape key deletion (#1258)

This change reworks delete handling to be more consistent with other properties,
by treating it as a virtual property (`deletedShape.{blendshapeName}`) instead of
a weird additional field of blendshape keys. This then fixes a number of issues
(e.g. broken preview for delete keys).

Fixes: #1253

Editor/ReactiveObjects/AnimationGeneration/AnimatedProperty.cs

@@ -8,7 +8,6 @@ namespace nadena.dev.modular_avatar.core.editor
         public TargetProp TargetProp { get; }
         public string ControlParam { get; set; }
 
-        public bool alwaysDeleted;
         public object currentState;
 
         // Objects which trigger deletion of this shape key. 

Editor/ReactiveObjects/AnimationGeneration/ReactionRule.cs

@@ -1,6 +1,5 @@
 using System.Collections.Generic;
 using System.Linq;
-using nadena.dev.modular_avatar.animation;
 using UnityEngine;
 
 namespace nadena.dev.modular_avatar.core.editor
@@ -9,8 +8,8 @@ namespace nadena.dev.modular_avatar.core.editor
     {
         public ReactionRule(TargetProp key, float value)
             : this(key, (object)value) { }
-            
+
-        public  ReactionRule(TargetProp key, UnityEngine.Object value)
+        public ReactionRule(TargetProp key, Object value)
             : this(key, (object)value) { }
             
         private ReactionRule(TargetProp key, object value)
@@ -31,15 +30,15 @@ namespace nadena.dev.modular_avatar.core.editor
 
         public bool InitiallyActive =>
             ((ControllingConditions.Count == 0) || ControllingConditions.All(c => c.InitiallyActive)) ^ Inverted;
-        public bool IsDelete;
 
         public bool Inverted;
 
         public bool IsConstant => ControllingConditions.Count == 0
                                   || ControllingConditions.All(c => c.IsConstant)
                                   || ControllingConditions.Any(c => c.IsConstant && !c.InitiallyActive);
-        public bool IsConstantOn => IsConstant && InitiallyActive;
 
+        public bool IsConstantActive => IsConstant && InitiallyActive ^ Inverted;
+        
         public override string ToString()
         {
             return $"AGK: {TargetProp}={Value}";
@@ -57,7 +56,6 @@ namespace nadena.dev.modular_avatar.core.editor
             }
             else return false;
             if (!ControllingConditions.SequenceEqual(other.ControllingConditions)) return false;
-            if (IsDelete || other.IsDelete) return false;
 
             return true;
         }

Editor/ReactiveObjects/AnimationGeneration/ReactiveObjectAnalyzer.LocateReactions.cs

@@ -124,50 +124,55 @@ namespace nadena.dev.modular_avatar.core.editor
                     var key = new TargetProp
                     {
                         TargetObject = renderer,
-                        PropertyName = "blendShape." + shape.ShapeName,
+                        PropertyName = BlendshapePrefix + shape.ShapeName
                     };
 
+                    var currentValue = renderer.GetBlendShapeWeight(shapeId);
                     var value = shape.ChangeType == ShapeChangeType.Delete ? 100 : shape.Value;
-                    if (!shapeKeys.TryGetValue(key, out var info))
+
+                    RegisterAction(key, renderer, currentValue, value, changer, shape);
+
+                    key = new TargetProp
                     {
-                        info = new AnimatedProperty(key, renderer.GetBlendShapeWeight(shapeId));
+                        TargetObject = renderer,
-                        shapeKeys[key] = info;
+                        PropertyName = DeletedShapePrefix + shape.ShapeName
+                    };
 
-                        // Add initial state
+                    value = shape.ChangeType == ShapeChangeType.Delete ? 1 : 0;
-                        var agk = new ReactionRule(key, value);
+                    RegisterAction(key, renderer, 0, value, changer, shape);
-                        agk.Value = renderer.GetBlendShapeWeight(shapeId);
-                        info.actionGroups.Add(agk);
-                    }
-
-                    var action = ObjectRule(key, changer, value);
-                    action.Inverted = _computeContext.Observe(changer, c => c.Inverted);
-                    var isCurrentlyActive = changer.gameObject.activeInHierarchy;
-
-                    if (shape.ChangeType == ShapeChangeType.Delete)
-                    {
-                        action.IsDelete = true;
-                        
-                        if (isCurrentlyActive) info.currentState = 100;
-
-                        info.actionGroups.Add(action); // Never merge
-
-                        continue;
-                    }
-
-                    if (changer.gameObject.activeInHierarchy) info.currentState = action.Value;
-
-                    if (info.actionGroups.Count == 0)
-                    {
-                        info.actionGroups.Add(action);
-                    }
-                    else if (!info.actionGroups[^1].TryMerge(action))
-                    {
-                        info.actionGroups.Add(action);
-                    }
                 }
             }
 
             return shapeKeys;
+
+            void RegisterAction(TargetProp key, SkinnedMeshRenderer renderer, float currentValue, float value,
+                ModularAvatarShapeChanger changer, ChangedShape shape)
+            {
+                if (!shapeKeys.TryGetValue(key, out var info))
+                {
+                    info = new AnimatedProperty(key, currentValue);
+                    shapeKeys[key] = info;
+
+                    // Add initial state
+                    var agk = new ReactionRule(key, value);
+                    agk.Value = currentValue;
+                    info.actionGroups.Add(agk);
+                }
+
+                var action = ObjectRule(key, changer, value);
+                action.Inverted = _computeContext.Observe(changer, c => c.Inverted);
+
+                if (changer.gameObject.activeInHierarchy) info.currentState = action.Value;
+
+                if (info.actionGroups.Count == 0)
+                {
+                    info.actionGroups.Add(action);
+                }
+                else if (!info.actionGroups[^1].TryMerge(action))
+                {
+                    info.actionGroups.Add(action);
+                }
+            }
         }
         
         private void FindMaterialSetters(Dictionary<TargetProp, AnimatedProperty> objectGroups, GameObject root)

Editor/ReactiveObjects/AnimationGeneration/ReactiveObjectAnalyzer.cs

@@ -18,6 +18,9 @@ namespace nadena.dev.modular_avatar.core.editor
         private readonly ndmf.BuildContext _context;
         private readonly AnimationServicesContext _asc;
         private Dictionary<string, float> _simulationInitialStates;
+
+        public const string BlendshapePrefix = "blendShape.";
+        public const string DeletedShapePrefix = "deletedShape.";
         
         public ImmutableDictionary<string, float> ForcePropertyOverrides { get; set; } = ImmutableDictionary<string, float>.Empty;
 
@@ -58,7 +61,6 @@ namespace nadena.dev.modular_avatar.core.editor
         {
             public Dictionary<TargetProp, AnimatedProperty> Shapes;
             public Dictionary<TargetProp, object> InitialStates;
-            public HashSet<TargetProp> DeletedShapes;
         }
 
         private static PropCache<GameObject, AnalysisResult> _analysisCache;
@@ -86,7 +88,6 @@ namespace nadena.dev.modular_avatar.core.editor
         /// </summary>
         /// <param name="root">The avatar root</param>
         /// <param name="initialStates">A dictionary of target property to initial state (float or UnityEngine.Object)</param>
-        /// <param name="deletedShapes">A hashset of blendshape properties which are always deleted</param>
         /// <returns></returns>
         public AnalysisResult Analyze(
             GameObject root
@@ -98,7 +99,6 @@ namespace nadena.dev.modular_avatar.core.editor
             {
                 result.Shapes = new();
                 result.InitialStates = new();
-                result.DeletedShapes = new();
                 return result;
             }
             
@@ -109,7 +109,7 @@ namespace nadena.dev.modular_avatar.core.editor
             ApplyInitialStateOverrides(shapes);
             AnalyzeConstants(shapes); 
             ResolveToggleInitialStates(shapes);
-            PreprocessShapes(shapes, out result.InitialStates, out result.DeletedShapes);
+            PreprocessShapes(shapes, out result.InitialStates);
             result.Shapes = shapes;
 
             return result;
@@ -165,7 +165,7 @@ namespace nadena.dev.modular_avatar.core.editor
                 group.actionGroups.RemoveAll(agk => agk.IsConstant && !agk.InitiallyActive);
                 
                 // Remove all action groups up until the last one where we're always on
-                var lastAlwaysOnGroup = group.actionGroups.FindLastIndex(ag => ag.IsConstantOn);
+                var lastAlwaysOnGroup = group.actionGroups.FindLastIndex(ag => ag.IsConstantActive);
                 if (lastAlwaysOnGroup > 0)
                     group.actionGroups.RemoveRange(0, lastAlwaysOnGroup - 1);
             }
@@ -264,18 +264,17 @@ namespace nadena.dev.modular_avatar.core.editor
         }
 
         /// <summary>
-        /// Determine initial state and deleted shapes for all properties
+        /// Determine initial state for all properties
         /// </summary>
         /// <param name="shapes"></param>
         /// <param name="initialStates"></param>
-        /// <param name="deletedShapes"></param>
+        private void PreprocessShapes(Dictionary<TargetProp, AnimatedProperty> shapes,
-        private void PreprocessShapes(Dictionary<TargetProp, AnimatedProperty> shapes, out Dictionary<TargetProp, object> initialStates, out HashSet<TargetProp> deletedShapes)
+            out Dictionary<TargetProp, object> initialStates)
         {
             // For each shapekey, determine 1) if we can just set an initial state and skip and 2) if we can delete the
             // corresponding mesh. If we can't, delete ops are merged into the main list of operations.
             
             initialStates = new Dictionary<TargetProp, object>();
-            deletedShapes = new HashSet<TargetProp>();
 
             foreach (var (key, info) in shapes.ToList())
             {
@@ -285,18 +284,6 @@ namespace nadena.dev.modular_avatar.core.editor
                     shapes.Remove(key);
                     continue;
                 }
-                
-                var deletions = info.actionGroups.Where(agk => agk.IsDelete).ToList();
-                if (deletions.Any(d => d.InitiallyActive))
-                {
-                    // always deleted
-                    shapes.Remove(key);
-                    deletedShapes.Add(key);
-                    continue;
-                }
-                
-                // Move deleted shapes to the end of the list, so they override all Set actions
-                info.actionGroups = info.actionGroups.Where(agk => !agk.IsDelete).Concat(deletions).ToList();
 
                 var initialState = info.actionGroups.Where(agk => agk.InitiallyActive)
                     .Select(agk => agk.Value)

Editor/ReactiveObjects/AnimationGeneration/ReactiveObjectPass.cs

@@ -2,7 +2,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Collections.Immutable;
 using System.Linq;
 using nadena.dev.modular_avatar.animation;
 using UnityEditor;
@@ -42,10 +41,11 @@ namespace nadena.dev.modular_avatar.core.editor
 
             var shapes = analysis.Shapes;
             var initialStates = analysis.InitialStates;
-            var deletedShapes = analysis.DeletedShapes;
             
             GenerateActiveSelfProxies(shapes);
 
+            ProcessMeshDeletion(initialStates, shapes);
+
             ProcessInitialStates(initialStates, shapes);
             ProcessInitialAnimatorVariables(shapes);
             
@@ -53,8 +53,6 @@ namespace nadena.dev.modular_avatar.core.editor
             {
                 ProcessShapeKey(groups);
             }
-
-            ProcessMeshDeletion(deletedShapes);
         }
 
         private void GenerateActiveSelfProxies(Dictionary<TargetProp, AnimatedProperty> shapes)
@@ -225,30 +223,65 @@ namespace nadena.dev.modular_avatar.core.editor
 
         #region Mesh processing
 
-        private void ProcessMeshDeletion(HashSet<TargetProp> deletedKeys)
+        private void ProcessMeshDeletion(Dictionary<TargetProp, object> initialStates,
+            Dictionary<TargetProp, AnimatedProperty> shapes)
         {
-            ImmutableDictionary<SkinnedMeshRenderer, List<TargetProp>> renderers = deletedKeys
+            var renderers = initialStates
-                .GroupBy(
+                .Where(kvp => kvp.Key.PropertyName.StartsWith(ReactiveObjectAnalyzer.DeletedShapePrefix))
-                    v => (SkinnedMeshRenderer) v.TargetObject
+                .Where(kvp => kvp.Key.TargetObject is SkinnedMeshRenderer)
-                ).ToImmutableDictionary(
+                .Where(kvp => kvp.Value is float f && f > 0.5f)
-                    g => (SkinnedMeshRenderer) g.Key,
+                // Filter any non-constant keys
-                    g => g.ToList()
+                .Where(kvp =>
-                );
+                {
+                    if (!shapes.ContainsKey(kvp.Key))
+                    {
+                        // Constant value
+                        return true;
+                    }
 
-            foreach (var (renderer, infos) in renderers)
+                    var lastGroup = shapes[kvp.Key].actionGroups.LastOrDefault();
+                    return lastGroup?.IsConstantActive == true && lastGroup.Value is float f && f > 0.5f;
+                })
+                .GroupBy(kvp => kvp.Key.TargetObject as SkinnedMeshRenderer)
+                .Select(grouping => (grouping.Key, grouping.Select(
+                    kvp => kvp.Key.PropertyName.Substring(ReactiveObjectAnalyzer.DeletedShapePrefix.Length)
+                ).ToList()))
+                .ToList();
+            foreach (var (renderer, shapeNamesToDelete) in renderers)
             {
                 if (renderer == null) continue;
 
                 var mesh = renderer.sharedMesh;
                 if (mesh == null) continue;
 
-                renderer.sharedMesh = RemoveBlendShapeFromMesh.RemoveBlendshapes(
+                var shapesToDelete = shapeNamesToDelete
-                    mesh,
+                    .Select(shape => mesh.GetBlendShapeIndex(shape))
-                    infos
+                    .Where(k => k >= 0)
-                        .Select(i => mesh.GetBlendShapeIndex(i.PropertyName.Substring("blendShape.".Length)))
+                    .ToList();
-                        .Where(k => k >= 0)
+
-                        .ToList()
+                renderer.sharedMesh = RemoveBlendShapeFromMesh.RemoveBlendshapes(mesh, shapesToDelete);
-                );
+
+                foreach (var name in shapeNamesToDelete)
+                {
+                    // Don't need to animate this anymore...!
+                    shapes.Remove(new TargetProp
+                    {
+                        TargetObject = renderer,
+                        PropertyName = ReactiveObjectAnalyzer.BlendshapePrefix + name
+                    });
+
+                    shapes.Remove(new TargetProp
+                    {
+                        TargetObject = renderer,
+                        PropertyName = ReactiveObjectAnalyzer.DeletedShapePrefix + name
+                    });
+
+                    initialStates.Remove(new TargetProp
+                    {
+                        TargetObject = renderer,
+                        PropertyName = ReactiveObjectAnalyzer.BlendshapePrefix + name
+                    });
+                }
             }
         }
 
@@ -257,10 +290,6 @@ namespace nadena.dev.modular_avatar.core.editor
         private void ProcessShapeKey(AnimatedProperty info)
         {
             // TODO: prune non-animated keys
-
-            // Check if this is non-animated and skip most processing if so
-            if (info.alwaysDeleted || info.actionGroups[^1].IsConstant) return;
-
             var asm = GenerateStateMachine(info);
             ApplyController(asm, "MA Responsive: " + info.TargetProp.TargetObject.name);
         }

Editor/ReactiveObjects/ShapeChangerPreview.cs

@@ -72,8 +72,8 @@ namespace nadena.dev.modular_avatar.core.editor
             var analysis = ReactiveObjectAnalyzer.CachedAnalyze(context, avatarRoot);
             var shapes = analysis.Shapes;
 
-            ImmutableDictionary<SkinnedMeshRenderer, ImmutableList<(int, float)>>.Builder rendererStates =
+            var rendererStates =
-                ImmutableDictionary.CreateBuilder<SkinnedMeshRenderer, ImmutableList<(int, float)>>(
+                ImmutableDictionary.CreateBuilder<SkinnedMeshRenderer, ImmutableDictionary<int, float>>(
                     
                 );
             var avatarRootTransform = avatarRoot.transform;
@@ -83,16 +83,29 @@ namespace nadena.dev.modular_avatar.core.editor
                 var target = prop.TargetProp;
                 if (target.TargetObject == null || target.TargetObject is not SkinnedMeshRenderer r) continue;
                 if (!r.transform.IsChildOf(avatarRootTransform)) continue;
-                if (!target.PropertyName.StartsWith("blendShape.")) continue;
 
+                var isDelete = false;
+                string shapeName = null;
+                if (target.PropertyName.StartsWith(ReactiveObjectAnalyzer.DeletedShapePrefix))
+                {
+                    isDelete = true;
+                    shapeName = target.PropertyName.Substring(ReactiveObjectAnalyzer.DeletedShapePrefix.Length);
+                }
+                else if (target.PropertyName.StartsWith(ReactiveObjectAnalyzer.BlendshapePrefix))
+                {
+                    shapeName = target.PropertyName.Substring(ReactiveObjectAnalyzer.BlendshapePrefix.Length);
+                }
+                else
+                {
+                    continue;
+                }
+                
                 var mesh = r.sharedMesh;
                 if (mesh == null) continue;
                 
-                var shapeName = target.PropertyName.Substring("blendShape.".Length);
-                
                 if (!rendererStates.TryGetValue(r, out var states))
                 {
-                    states = ImmutableList<(int, float)>.Empty;
+                    states = ImmutableDictionary<int, float>.Empty;
                     rendererStates[r] = states;
                 }
                 
@@ -103,15 +116,30 @@ namespace nadena.dev.modular_avatar.core.editor
                 if (activeRule == null || activeRule.Value is not float value) continue;
                 if (activeRule.ControllingObject == null) continue; // default value is being inherited
 
-                value = Math.Clamp(value, 0, 100);
+                if (isDelete)
-                
+                {
-                if (activeRule.IsDelete) value = -1;
+                    if (value < 0.5f) continue;
-                
+                    value = -1;
-                states = states.Add((index, value));
+                }
+                else
+                {
+                    if (states.ContainsKey(index))
+                    {
+                        // Delete takes precedence over set in preview
+                        continue;
+                    }
+
+                    value = Math.Clamp(value, 0, 100);
+                }
+
+                states = states.SetItem(index, value);
                 rendererStates[r] = states;
             }
-            
+
-            return rendererStates.ToImmutableDictionary();
+            return rendererStates.ToImmutableDictionary(
+                kvp => kvp.Key,
+                kvp => kvp.Value.Select(shapePair => (shapePair.Key, shapePair.Value)
+                ).ToImmutableList());
         }
         
         private IEnumerable<RenderGroup> ShapesToGroups(GameObject avatarRoot, ImmutableDictionary<SkinnedMeshRenderer, ImmutableList<(int, float)>> shapes)

Editor/ReactiveObjects/Simulator/ROSimulator.cs

@@ -471,7 +471,7 @@ namespace nadena.dev.modular_avatar.core.editor.Simulator
                     var f_set_inactive = effectGroup.Q<VisualElement>("effect__set-inactive");
                     var f_value = effectGroup.Q<FloatField>("effect__value");
                     var f_material = effectGroup.Q<ObjectField>("effect__material");
-                    var f_delete = effectGroup.Q("effect__deleted");
+                    var f_delete = effectGroup.Q<TextField>("effect__deleted");
                     
                     f_target_component.style.display = DisplayStyle.None;
                     f_target_component.SetEnabled(false);
@@ -504,9 +504,10 @@ namespace nadena.dev.modular_avatar.core.editor.Simulator
                         f_property.value = targetProp.PropertyName;
                         f_property.style.display = DisplayStyle.Flex;
 
-                        if (reactionRule.IsDelete)
+                        if (reactionRule.TargetProp.PropertyName.StartsWith(ReactiveObjectAnalyzer.DeletedShapePrefix))
                         {
                             f_delete.style.display = DisplayStyle.Flex;
+                            f_delete.value = reactionRule.Value is > 0.5f ? "DELETE" : "RETAIN";
                         } else if (reactionRule.Value is float f)
                         {
                             f_value.SetValueWithoutNotify(f);

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@@ -0,0 +1,666 @@
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UnitTests~/ReactiveComponent/DeletionTest.prefab.meta

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UnitTests~/ReactiveComponent/ShapeDeletionAnalysis.cs

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+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using modular_avatar_tests;
+using nadena.dev.modular_avatar.core;
+using nadena.dev.modular_avatar.core.editor;
+using NUnit.Framework;
+using UnityEngine;
+
+public class ShapeDeletionAnalysis : TestBase
+{
+    [Test]
+    public void BasicShapeDeletionAnalysis()
+    {
+        var root = CreatePrefab("DeletionTest.prefab");
+
+        var mesh = AssertPreviewDeletion(root);
+
+        AssertBuildDeletion(mesh, root);
+    }
+
+    [Test]
+    public void WhenShapeDeletionIsConditionedOnSubsequentChanger_DoesNotDelete()
+    {
+        var root = CreatePrefab("DeletionTest.prefab");
+        root.transform.Find("MenuSet").gameObject.SetActive(true);
+
+        AssertPreviewDeletion(root);
+        AssertNoMeshDeletion(root);
+        
+        var mesh = root.GetComponentInChildren<SkinnedMeshRenderer>();
+        Assert.AreEqual(100, mesh.GetBlendShapeWeight(mesh.sharedMesh.GetBlendShapeIndex("bottom")));
+    }
+
+
+    [Test]
+    public void WhenShapeDeletionIsConditionedOnItself_DoesNotDelete()
+    {
+        var root = CreatePrefab("DeletionTest.prefab");
+        root.transform.Find("Delete").gameObject.AddComponent<ModularAvatarMenuItem>().InitSettings();
+        
+        AssertNoPreviewDeletion(root);
+        AssertNoMeshDeletion(root);
+        
+        var mesh = root.GetComponentInChildren<SkinnedMeshRenderer>();
+        // deletion action is initially off, so we use the shape changer above it, which is set to 50.
+        Assert.AreEqual(50f, mesh.GetBlendShapeWeight(mesh.sharedMesh.GetBlendShapeIndex("bottom")));
+    }
+    
+    private static void AssertBuildDeletion(SkinnedMeshRenderer mesh, GameObject root)
+    {
+        var originalSharedMesh = mesh.sharedMesh;
+        AvatarProcessor.ProcessAvatar(root);
+        Assert.AreNotEqual(originalSharedMesh, mesh.sharedMesh);
+
+        Assert.IsTrue(mesh.sharedMesh.vertices.All(v => v.z >= 0));
+    }
+
+    private static SkinnedMeshRenderer AssertPreviewDeletion(GameObject root)
+    {
+        var mesh = root.GetComponentInChildren<SkinnedMeshRenderer>();
+        var analysis = new ReactiveObjectAnalyzer().Analyze(root);
+        var deletedShape = analysis.Shapes.GetValueOrDefault(new TargetProp()
+        {
+            TargetObject = mesh,
+            PropertyName = "deletedShape.bottom"
+        });
+        Assert.IsNotNull(deletedShape);
+        var activeGroup = deletedShape.actionGroups.LastOrDefault(ag => ag.InitiallyActive);
+        Assert.AreEqual(1.0f, activeGroup?.Value);
+        return mesh;
+    }
+    
+    private static void AssertNoPreviewDeletion(GameObject root)
+    {
+        var mesh = root.GetComponentInChildren<SkinnedMeshRenderer>();
+        var analysis = new ReactiveObjectAnalyzer().Analyze(root);
+        var deletedShape = analysis.Shapes.GetValueOrDefault(new TargetProp()
+        {
+            TargetObject = mesh,
+            PropertyName = "deletedShape.bottom"
+        });
+        if (deletedShape != null)
+        {
+            var activeGroup = deletedShape.actionGroups.LastOrDefault(ag => ag.InitiallyActive);
+            Assert.IsFalse(activeGroup?.Value is float f && f > 0);
+        }
+        
+    }
+
+    private static void AssertNoMeshDeletion(GameObject root)
+    {
+        var mesh = root.GetComponentInChildren<SkinnedMeshRenderer>();
+        var originalSharedMesh = mesh.sharedMesh;
+        AvatarProcessor.ProcessAvatar(root);
+        Assert.AreEqual(originalSharedMesh, mesh.sharedMesh);
+    }
+}

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