[VFX] Release batch instance when disabled

Author: gabrieldelacruz

Packages/com.unity.visualeffectgraph/Editor/Inspector/VisualEffectEditor.cs

@@ -72,6 +72,7 @@ class VisualEffectEditor : Editor
         SerializedProperty m_RandomSeed;
         SerializedProperty m_VFXPropertySheet;
         SerializedProperty m_AllowInstancing;
+        SerializedProperty m_ReleaseInstanceOnDisable;
 
         RendererEditor m_RendererEditor;
 
@@ -107,6 +108,7 @@ protected void OnEnable()
             m_VisualEffectAsset = serializedObject.FindProperty("m_Asset");
             m_VFXPropertySheet = m_SingleSerializedObject.FindProperty("m_PropertySheet");
             m_AllowInstancing = serializedObject.FindProperty("m_AllowInstancing");
+            m_ReleaseInstanceOnDisable = serializedObject.FindProperty("m_ReleaseInstanceOnDisable");
 
             var renderers = targets.Cast<Component>().Select(t => t.GetComponent<VFXRenderer>()).ToArray();
             m_RendererEditor = new RendererEditor(renderers);
@@ -1271,13 +1273,14 @@ private void DrawInstancingProperties()
                 {
                     EditorGUI.BeginChangeCheck();
                     EditorGUILayout.PropertyField(m_AllowInstancing, Contents.allowInstancing);
+                    EditorGUILayout.PropertyField(m_ReleaseInstanceOnDisable, Contents.releaseInstanceOnDisable);
                     if (EditorGUI.EndChangeCheck())
                     {
                         serializedObject.ApplyModifiedProperties();
 
                         foreach (var visualEffect in targets.OfType<VisualEffect>())
                         {
-                            visualEffect.RecreateData();
+                            visualEffect.RecreateBatchInstance();
                         }
                     }
                 }
@@ -1503,6 +1506,7 @@ protected static class Contents
             public static readonly GUILayoutOption playRateDropdownWidth = GUILayout.Width(40);
 
             public static readonly GUIContent allowInstancing = EditorGUIUtility.TrTextContent("Allow Instancing", "When enabled, the effect will try to be batched with other of the same type.");
+            public static readonly GUIContent releaseInstanceOnDisable = EditorGUIUtility.TrTextContent("Release Instance On Disable", "When enabled, the effect instance will be created when the component is enabled, and released when it is disabled, to optimize memory usage.");
 
             public static readonly GUIContent graphInBundle = EditorGUIUtility.TrTextContent("Exposed properties are hidden in the Inspector when Visual Effect Assets are stored in Asset Bundles.");
             public static readonly GUIContent play = new GUIContent("Send Play Event");

Tests/SRPTests/Packages/com.unity.testing.visualeffectgraph/Tests/Runtime/VFXRuntimeTests.cs

@@ -576,6 +576,50 @@ public IEnumerator Load_Keyword_Scene_With_Instancing()
         }
 #endif
 
+        private IEnumerator Release_Batch_Instance_When_Disabled_CompareInstanceCount(string testName, VisualEffectAsset vfxAsset, uint expectedInstanceCount)
+        {
+            yield return null;
+
+            uint currentInstanceCount = VFXManager.GetBatchedEffectInfo(vfxAsset).activeInstanceCount;
+            Assert.AreEqual(expectedInstanceCount, currentInstanceCount, $"{testName}: Instance count should match:");
+        }
+
+
+        [UnityTest]
+        public IEnumerator Release_Batch_Instance_When_Disabled()
+        {
+            SceneManagement.SceneManager.LoadScene("Packages/com.unity.testing.visualeffectgraph/Scenes/024_StripIndirectAndSorting.unity");
+            yield return null;
+
+            VisualEffect vfxComponent = null;
+            foreach (var component in Object.FindObjectsByType<VisualEffect>(FindObjectsSortMode.None))
+            {
+                if (component.visualEffectAsset.name == "024_StripIndirectAndSorting_NoIndirect")
+                {
+                    vfxComponent = component;
+                    break;
+                }
+            }
+            var vfxAsset = vfxComponent.visualEffectAsset;
+
+            uint initialInstanceCount = VFXManager.GetBatchedEffectInfo(vfxAsset).activeInstanceCount;
+
+            vfxComponent.enabled = false;
+            yield return Release_Batch_Instance_When_Disabled_CompareInstanceCount("Disable keeps instances by default", vfxAsset, initialInstanceCount);
+
+            vfxComponent.releaseInstanceWhenDisabled = true;
+            yield return Release_Batch_Instance_When_Disabled_CompareInstanceCount("Setting releaseInstanceWhenDisabled releases instance if already disabled", vfxAsset, initialInstanceCount - 1);
+
+            vfxComponent.enabled = true;
+            yield return Release_Batch_Instance_When_Disabled_CompareInstanceCount("Enabling the component again recreates the instance", vfxAsset, initialInstanceCount);
+
+            vfxComponent.enabled = false;
+            yield return Release_Batch_Instance_When_Disabled_CompareInstanceCount("Disabling the component with releaseInstanceWhenDisabled releases the instance", vfxAsset, initialInstanceCount - 1);
+
+            vfxComponent.releaseInstanceWhenDisabled = false;
+            yield return Release_Batch_Instance_When_Disabled_CompareInstanceCount("Clearing releaseInstanceWhenDisabled when disabled recreates the instance", vfxAsset, initialInstanceCount);
+        }
+
         private static Vector4[] s_SampleGradient_Branch_Instancing_Readback = null;
 
         static void SampleGradient_Branch_Instancing_Readback(AsyncGPUReadbackRequest request)