Add Modification API:

- The Modification API is designed specifically for the creation and distribution of modular prefabs, where a developer generates assets on their machine and distributes those generated assets to their users.
  - Add AacFlModification class.
  - Add (AacFlBase).Modification() which returns a AacFlModification.

Packages/dev.hai-vr.animator-as-code.v1/V1/Editor/Aac.cs

@@ -523,13 +523,15 @@ namespace AnimatorAsCode.V1
             return new AacFlClip(_configuration, clip);
         }
         
-        /// Create a new BlendTree asset with a name. However, the name is only used as a suffix for the asset. The asset is generated into the container.
+        /// Create a new BlendTree asset with a name. However, the name is only used as a suffix for the asset. The asset is generated into the container.<br/>
+        /// Added in 1.3.0.
         public AacFlNonInitializedBlendTree NewBlendTree(string name)
         {
             return new AacFlNonInitializedBlendTree(AacInternals.NewBlendTreeAsRaw(_configuration, name));
         }
 
-        /// Create a new BlendTree asset with a name and returns a native BlendTree object. However, the name is only used as a suffix for the asset. The asset is generated into the container. You may use NewBlendTree() instead to obtain a fluent interface.
+        /// Create a new BlendTree asset with a name and returns a native BlendTree object. However, the name is only used as a suffix for the asset. The asset is generated into the container. You may use NewBlendTree() instead to obtain a fluent interface.<br/>
+        /// Added in 1.3.0.
         public BlendTree NewBlendTreeAsRaw(string name)
         {
             return AacInternals.NewBlendTreeAsRaw(_configuration, name);
@@ -640,6 +642,13 @@ namespace AnimatorAsCode.V1
         {
             return new AacFlNoAnimator();
         }
+
+        /// Returns a new AacFlModification instance, granting you access to this destructive modification API. You will need to reuse this object throughout.<br/>
+        /// Added in 1.3.0.
+        public AacFlModification Modification()
+        {
+            return new AacFlModification(_configuration, this);
+        }
     }
 
     public class AacFlNoAnimator

Packages/dev.hai-vr.animator-as-code.v1/V1/Editor/AacFlModification.cs

@@ -0,0 +1,108 @@
+using System;
+using System.Collections.Generic;
+using UnityEditor;
+using UnityEditor.Animations;
+using Object = UnityEngine.Object;
+using UnityEngine;
+
+// ReSharper disable once CheckNamespace
+namespace AnimatorAsCode.V1
+{
+    public class AacFlModification
+    {
+        private readonly AacConfiguration _configuration;
+        private readonly AacFlBase _base;
+        
+        private readonly HashSet<Object> _objects = new();
+
+        internal AacFlModification(AacConfiguration configuration, AacFlBase originalBase)
+        {
+            _configuration = configuration;
+            _base = originalBase;
+        }
+        
+        /// Immediately removes all layers and all parameters from the given AnimatorController, and returns a AacFlController that will edit the given AnimatorController.<br/>
+        /// This AnimatorController instance is memorized in the current AacFlModification instance memory.<br/>
+        /// Note: The AnimatorController class is editor-only, so they can't be referenced inside scene components or asset objects. If you have a RuntimeAnimatorController instance, you should cast it to AnimatorController.
+        public AacFlController ResetAnimatorController(AnimatorController controllerToReset)
+        {
+            _objects.Add(controllerToReset);
+            
+            Internal_ClearAnimatorController(controllerToReset);
+
+            return new AacFlController(_configuration, controllerToReset, _base);
+        }
+
+        /// Immediately removes all curves on the clip, and returns a AacFlClip that will edit the given AnimationClip.<br/>
+        /// This does not reset any other attribute of the clip (e.g., is looping, etc.).<br/>
+        /// This AnimationClip instance is memorized in the current AacFlModification instance memory.
+        public AacFlClip ResetClip(AnimationClip clipToReset)
+        {
+            _objects.Add(clipToReset);
+            
+            clipToReset.ClearCurves();
+
+            return new AacFlClip(_configuration, clipToReset);
+        }
+
+        /// Immediately clears the list of children in the given BlendTree, sets the parameters to empty strings, and returns a AacFlNonInitializedBlendTree that will edit the given BlendTree.<br/>
+        /// This does not reset any other attribute of the blend tree (e.g., automatic thresholds, etc.).<br/>
+        /// This BlendTree instance is memorized in the current AacFlModification instance memory.<br/>
+        /// Note: The BlendTree class is editor-only, so they can't be referenced inside scene components or asset objects. If you have a Motion instance that is a BlendTree instance, you should cast it to BlendTree.
+        public AacFlNonInitializedBlendTree ResetBlendTree(BlendTree blendTreeToReset)
+        {
+            _objects.Add(blendTreeToReset);
+            
+            blendTreeToReset.children = Array.Empty<ChildMotion>();
+            blendTreeToReset.blendParameter = "";
+            blendTreeToReset.blendParameterY = "";
+
+            return new AacFlNonInitializedBlendTree(blendTreeToReset);
+        }
+
+        /// Immediately removes all layers and all parameters from the given AnimatorController.<br/>
+        /// This AnimatorController instance is memorized in the current AacFlModification instance memory.<br/>
+        /// Note: The AnimatorController class is editor-only, so they can't be referenced inside scene components or asset objects. If you have a RuntimeAnimatorController instance, you should cast it to AnimatorController.
+        public AacFlModification ClearAnimatorController(AnimatorController controllerToReset)
+        {
+            _objects.Add(controllerToReset);
+            
+            Internal_ClearAnimatorController(controllerToReset);
+
+            return this;
+        }
+
+        /// Returns a AacFlController that will edit the given AnimatorController. This does not reset the AnimatorController.<br/>
+        /// This AnimatorController instance is memorized in the current AacFlModification instance memory.<br/>
+        /// Note: The AnimatorController class is editor-only, so they can't be referenced inside scene components or asset objects. If you have a RuntimeAnimatorController instance, you should cast it to AnimatorController.
+        public AacFlController EditAnimatorController(AnimatorController controllerToReset)
+        {
+            _objects.Add(controllerToReset);
+            
+            return new AacFlController(_configuration, controllerToReset, _base);
+        }
+
+        /// Calls `EditorUtility.SetDirty(...)` on every single AnimatorController, AnimationClip, and BlendTree asset instances previously memorized by this AacFlModification instance.
+        public void SetDirtyAll()
+        {
+            foreach (var obj in _objects)
+            {
+                EditorUtility.SetDirty(obj);
+            }
+        }
+
+        private static void Internal_ClearAnimatorController(AnimatorController controllerToReset)
+        {
+            while (controllerToReset.layers.Length > 0)
+            {
+                controllerToReset.RemoveLayer(0);
+            }
+            
+            var parameters = controllerToReset.parameters;
+            for (var i = parameters.Length - 1; i >= 0; i--)
+            {
+                controllerToReset.RemoveParameter(i);
+            }
+        }
+    }
+}

Packages/dev.hai-vr.animator-as-code.v1/V1/Editor/AacFlModification.cs.meta

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