chore(release): 4.12.1 [skip ci]

## [4.12.1](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.12.0...v4.12.1) (2026-03-24)

### Bug Fixes

* ignore "EditorOnly" tagged gameObjects on refresh ([031d46a](031d46a321))

.github/workflows/release.yml

@@ -27,10 +27,10 @@ jobs:
       split_to: ${{ steps.summary.outputs.split_to }}
     steps:
       - name: 🚚 Checkout (${{ github.ref_name }})
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: 🔖 Run semantic release
-        uses: cycjimmy/semantic-release-action@v4
+        uses: cycjimmy/semantic-release-action@v5
         id: release
         with:
           working_directory: Packages/src
@@ -67,7 +67,7 @@ jobs:
       contents: write
     steps:
       - name: 🚚 Checkout (${{ needs.release.outputs.merge_to }})
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: ${{ needs.release.outputs.merge_to }}
           fetch-depth: 0
@@ -88,7 +88,7 @@ jobs:
       contents: write
     steps:
       - name: 🚚 Checkout (${{ needs.release.outputs.tag }})
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: ${{ needs.release.outputs.tag }}
           fetch-depth: 0

.github/workflows/test.yml

@@ -10,6 +10,7 @@ env:
   MINIMUM_VERSION: 2019.4
   # EXCLUDE_FILTER: The excluded versions of Unity.
   EXCLUDE_FILTER: "(2020.2.0|2021.1|2023.3)"
+  PROJECT_PATH: .
 
 on:
   workflow_dispatch:
@@ -21,7 +22,7 @@ on:
   push:
     branches:
       - develop
-      - develop-preview
+      - "develop-*"
     tags:
       - "!*"
     paths-ignore:
@@ -71,11 +72,11 @@ jobs:
     steps:
       - name: 🚚 Checkout ($${{ github.ref }})
         if: github.event_name == 'push'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
 
       - name: 🚚 Checkout pull request (pull_request_target)
         if: github.event_name == 'pull_request_target'
-        uses: actions/checkout@v4
+        uses: actions/checkout@v5
         with:
           ref: ${{ github.event.pull_request.head.sha }}
           fetch-depth: 0
@@ -85,25 +86,27 @@ jobs:
         run: |
           git config user.name "GitHub Actions"
           git config user.email "actions@github.com"
-          git merge origin/${{ github.event.pull_request.base.ref }} --no-edit
+          git rebase ${{ github.event.pull_request.base.sha }}
+          git log --oneline -n 10
 
       - name: 📥 Cache library
         uses: actions/cache@v4
         with:
-          path: Library
-          key: Library-${{ matrix.unityVersion }}-${{ github.event.pull_request.head.sha || github.sha }}
+          path: ${{ env.PROJECT_PATH }}/Library
+          key: ${{ env.PROJECT_PATH }}-Library-${{ matrix.unityVersion }}-${{ github.event.pull_request.head.sha || github.sha }}
           restore-keys: |
-            Library-${{ matrix.unityVersion }}-
-            Library-
+            ${{ env.PROJECT_PATH }}-Library-${{ matrix.unityVersion }}-
+            ${{ env.PROJECT_PATH }}-Library-
 
       - name: 🛠️ Build Unity Project (Test)
-        uses: game-ci/unity-builder@v4
+        uses: game-ci/unity-builder@main
         timeout-minutes: 45
         with:
           customImage: ghcr.io/mob-sakai/unity3d:${{ matrix.unityVersion }}
           targetPlatform: StandaloneLinux64
           allowDirtyBuild: true
           customParameters: -nographics
+          projectPath: ${{ env.PROJECT_PATH }}
         env:
           UNITY_EMAIL: ${{ secrets.UNITY_EMAIL }}
           UNITY_PASSWORD: ${{ secrets.UNITY_PASSWORD }}
@@ -118,6 +121,7 @@ jobs:
           customParameters: -nographics
           checkName: ${{ matrix.unityVersion }} Test Results
           githubToken: ${{ github.token }}
+          projectPath: ${{ env.PROJECT_PATH }}
         env:
           UNITY_EMAIL: ${{ secrets.UNITY_EMAIL }}
           UNITY_PASSWORD: ${{ secrets.UNITY_PASSWORD }}

Assets/ProjectSettings/NanoMonitor.asset

@@ -18,11 +18,12 @@ MonoBehaviour:
   m_EnabledInEditor: 1
   m_AlwaysIncludeAssembly: 1
   m_InstantiateOnLoad: 1
-  m_Prefab: {fileID: 7211429669315726685, guid: b73940fc30a2f4eb9a73783e9c1f8da6,
+  m_Prefab: {fileID: 4567906826058368312, guid: 7cebff2d255b9433cbe23b243c193329,
     type: 3}
   m_Interval: 0.5
   m_Anchor: 0
   m_Width: 750
+  m_HelpUrl: https://github.com/mob-sakai/ParticleEffectForUGUI
   m_CustomMonitorItems:
   - m_Format: Screen:{0}x{1}
     m_Arg0:

Assets/ProjectSettings/NanoMonitor.prefab.meta

@@ -1,7 +0,0 @@
-fileFormatVersion: 2
-guid: b73940fc30a2f4eb9a73783e9c1f8da6
-PrefabImporter:
-  externalObjects: {}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Assets/ProjectSettings/UIParticleProjectSettings.asset

@@ -10,7 +10,7 @@ MonoBehaviour:
   m_Enabled: 1
   m_EditorHideFlags: 0
   m_Script: {fileID: 11500000, guid: f22a23b9d98e440478697f4adf30e61c, type: 3}
-  m_Name: UIParticle
+  m_Name: UIParticleProjectSettings
   m_EditorClassIdentifier: 
   m_EnableLinearToGamma: 1
   m_HideGeneratedObjects: 1

Assets/ProjectSettings/UIParticleProjectSettings.asset.meta

@@ -1,5 +1,5 @@
 fileFormatVersion: 2
-guid: 4b9df7b8a4193489299b8f477348ae0c
+guid: a5b9278dfbd194d04b1c6ae7031928c1
 NativeFormatImporter:
   externalObjects: {}
   mainObjectFileID: 11400000

Assets/Tests/Editor/NewTestScript.cs

@@ -1,16 +1,21 @@
 using System.Collections;
+using Coffee.UIParticleInternal;
 using NUnit.Framework;
+using UnityEngine;
 using UnityEngine.TestTools;
 
 namespace Coffee.UIParticle.Editor.Tests
 {
     public class NewTestScript
     {
-        // A Test behaves as an ordinary method
-        [Test]
-        public void NewTestScriptSimplePasses()
+        [TestCase(-1)]
+        [TestCase(0)]
+        [TestCase(2048)]
+        [TestCase(3000)]
+        public void GetParticleArray(int requiredSize)
         {
-            // Use the Assert class to test conditions
+            var array = ParticleSystemExtensions.GetParticleArray(requiredSize);
+            Debug.Log($"requiredSize: {requiredSize}, array.Length: {array.Length}");
         }
 
         // A UnityTest behaves like a coroutine in Play Mode. In Edit Mode you can use

Packages/manifest.json

@@ -1,6 +1,7 @@
 {
   "dependencies": {
     "com.coffee.development": "https://github.com/mob-sakai/Coffee.Internal.git?path=Packages/Development",
+    "com.coffee.minimal-resource": "https://github.com/mob-sakai/Coffee.Internal.git?path=Packages/MinimalResource",
     "com.coffee.nano-monitor": "https://github.com/mob-sakai/Coffee.Internal.git?path=Packages/NanoMonitor",
     "com.unity.ide.rider": "3.0.31",
     "com.unity.test-framework": "1.1.33",

Packages/packages-lock.json

@@ -5,7 +5,14 @@
       "depth": 0,
       "source": "git",
       "dependencies": {},
-      "hash": "4e5f735ccf956ee469b5014ae781068c49a2825d"
+      "hash": "3c280f1a8f4db5038b881ff07f270efd9638fa31"
+    },
+    "com.coffee.minimal-resource": {
+      "version": "https://github.com/mob-sakai/Coffee.Internal.git?path=Packages/MinimalResource",
+      "depth": 0,
+      "source": "git",
+      "dependencies": {},
+      "hash": "3c280f1a8f4db5038b881ff07f270efd9638fa31"
     },
     "com.coffee.nano-monitor": {
       "version": "https://github.com/mob-sakai/Coffee.Internal.git?path=Packages/NanoMonitor",
@@ -14,7 +21,7 @@
       "dependencies": {
         "com.unity.ugui": "1.0.0"
       },
-      "hash": "4e5f735ccf956ee469b5014ae781068c49a2825d"
+      "hash": "3c280f1a8f4db5038b881ff07f270efd9638fa31"
     },
     "com.coffee.ui-particle": {
       "version": "file:src",

Packages/src/CHANGELOG.md

@@ -1,3 +1,72 @@
+## [4.12.1](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.12.0...v4.12.1) (2026-03-24)
+
+
+### Bug Fixes
+
+* ignore "EditorOnly" tagged gameObjects on refresh ([031d46a](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/031d46a3216c942d2d1a6ccfadf5f0b9e3ce3006))
+
+# [4.12.0](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.11.4...v4.12.0) (2026-03-24)
+
+
+### Features
+
+* explicit null checks ([5384f61](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/5384f61c569e9f78ff9d5b45acfc6f5c2f021a87))
+
+## [4.11.4](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.11.3...v4.11.4) (2025-12-24)
+
+
+### Bug Fixes
+
+* add early return for case where subEmitter module is disabled ([d1386a1](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/d1386a12216743a6e09f1b9b87bea1dfcf7702e4))
+* avoid endless loop ([eb2e862](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/eb2e862e80e549c8cf16ddfed776c101c2413bac)), closes [#392](https://github.com/mob-sakai/ParticleEffectForUGUI/issues/392)
+
+## [4.11.3](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.11.2...v4.11.3) (2025-10-14)
+
+
+### Bug Fixes
+
+* fix icon ([a9461ec](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/a9461ecb4d40d7fe878e12465d6e38faae7ae65b))
+* fix URL link in README ([1c8c65d](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/1c8c65d25e7f6fe7b1d20da4461333df8fc7578e)), closes [#376](https://github.com/mob-sakai/ParticleEffectForUGUI/issues/376)
+* fix: second and subsequent bursts not displayed when world simulation and non-looping ([df2f3ca](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/df2f3caafbe279f1457d74f8183cb561ac14aa17)), closes [#326](https://github.com/mob-sakai/ParticleEffectForUGUI/issues/326)
+* UIParticle in canvas with 0f-0.01f alpha value does not start to play until alpha value is greater than 0.01f, causes play calls to be delayed unintentionally if canvas alpha value is set to mentioned value range ([38aec2e](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/38aec2ea1afd77677d629c86665a3342d92e49d9))
+
+## [4.11.2](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.11.1...v4.11.2) (2025-03-15)
+
+
+### Bug Fixes
+
+* IL2CPP build fails on older versions of Unity ([0da6525](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/0da652520cd165b43de7404c0b0ab1fbcf9349d1))
+* NRE on enable ([0cff50e](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/0cff50ef696aa53fb7c46a9a737b7cf3a05b7b9b)), closes [#359](https://github.com/mob-sakai/ParticleEffectForUGUI/issues/359)
+
+## [4.11.1](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.11.0...v4.11.1) (2025-02-21)
+
+
+### Bug Fixes
+
+* component icons will no longer be displayed in the scene view ([6dfbdae](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/6dfbdae38d3822ab9c2c6f0e4ca1ca32ee98a239))
+
+# [4.11.0](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.10.7...v4.11.0) (2025-02-21)
+
+
+### Features
+
+* add 'TimeScaleMultiplier' option ([925af0b](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/925af0b6046f65f23a778f67cefa8ff9cbedb513))
+
+## [4.10.7](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.10.6...v4.10.7) (2025-01-14)
+
+
+### Bug Fixes
+
+* editor crashed on exit play mode (editor, windows) ([47ee45c](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/47ee45cbbe651a8f87ca2b8a3948f8b88db8211e)), closes [#351](https://github.com/mob-sakai/ParticleEffectForUGUI/issues/351)
+
+## [4.10.6](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.10.5...v4.10.6) (2025-01-03)
+
+
+### Bug Fixes
+
+* sub-emitter particles may not render correctly in certain scenarios ([8276684](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/8276684c3b1646f0490ed64557547ba15281664a)), closes [#348](https://github.com/mob-sakai/ParticleEffectForUGUI/issues/348)
+* sub-emitter's `inherit velocity` module doubles at runtime ([67de3d1](https://github.com/mob-sakai/ParticleEffectForUGUI/commit/67de3d1bd3e16dc9b564625cb990c53d75769506)), closes [#349](https://github.com/mob-sakai/ParticleEffectForUGUI/issues/349)
+
 ## [4.10.5](https://github.com/mob-sakai/ParticleEffectForUGUI/compare/v4.10.4...v4.10.5) (2024-12-23)
 
 

Packages/src/Editor/AnimatablePropertyEditor.cs

@@ -76,7 +76,7 @@ namespace Coffee.UIExtensions
             for (var j = 0; j < mats.Count; j++)
             {
                 var mat = mats[j];
-                if (!mat || !mat.shader) continue;
+                if (mat == null || mat.shader == null) continue;
 
                 for (var i = 0; i < ShaderUtil.GetPropertyCount(mat.shader); i++)
                 {

Packages/src/Editor/UIParticleEditor.cs

@@ -62,6 +62,7 @@ namespace Coffee.UIExtensions
         private SerializedProperty _autoScalingMode;
         private SerializedProperty _useCustomView;
         private SerializedProperty _customViewSize;
+        private SerializedProperty _timeScaleMultiplier;
         private ReorderableList _ro;
         private bool _showMax;
         private bool _is3DScaleMode;
@@ -100,6 +101,7 @@ namespace Coffee.UIExtensions
             _autoScalingMode = serializedObject.FindProperty("m_AutoScalingMode");
             _useCustomView = serializedObject.FindProperty("m_UseCustomView");
             _customViewSize = serializedObject.FindProperty("m_CustomViewSize");
+            _timeScaleMultiplier = serializedObject.FindProperty("m_TimeScaleMultiplier");
 
             var sp = serializedObject.FindProperty("m_Particles");
             _ro = new ReorderableList(sp.serializedObject, sp, true, true, true, true)
@@ -108,7 +110,7 @@ namespace Coffee.UIExtensions
                 {
                     var ps = sp.GetArrayElementAtIndex(index).objectReferenceValue as ParticleSystem;
                     var materialCount = 0;
-                    if (ps && ps.TryGetComponent<ParticleSystemRenderer>(out var psr))
+                    if (ps != null && ps.TryGetComponent<ParticleSystemRenderer>(out var psr))
                     {
                         materialCount = psr.sharedMaterials.Length;
                     }
@@ -122,7 +124,7 @@ namespace Coffee.UIExtensions
                     var p = sp.GetArrayElementAtIndex(index);
                     EditorGUI.ObjectField(rect, p, GUIContent.none);
                     var ps = p.objectReferenceValue as ParticleSystem;
-                    if (!ps || !ps.TryGetComponent<ParticleSystemRenderer>(out var psr)) return;
+                    if (ps == null || !ps.TryGetComponent<ParticleSystemRenderer>(out var psr)) return;
 
                     rect.x += 15;
                     rect.width -= 15;
@@ -189,7 +191,7 @@ namespace Coffee.UIExtensions
         public override void OnInspectorGUI()
         {
             var current = target as UIParticle;
-            if (!current) return;
+            if (current == null) return;
 
             Profiler.BeginSample("(UIP:E) OnInspectorGUI");
             serializedObject.Update();
@@ -244,6 +246,9 @@ namespace Coffee.UIExtensions
                 _customViewSize.floatValue = Mathf.Max(0.1f, _customViewSize.floatValue);
             }
 
+            // Time Scale Multiplier
+            EditorGUILayout.PropertyField(_timeScaleMultiplier);
+
             // Target ParticleSystems.
             EditorGUI.BeginChangeCheck();
             _ro.DoLayoutList();
@@ -262,7 +267,7 @@ namespace Coffee.UIExtensions
             Profiler.BeginSample("(UIP:E) Non-UI built-in shader is not supported.");
             foreach (var mat in s_TempMaterials)
             {
-                if (!mat || !mat.shader) continue;
+                if (mat == null || mat.shader == null) continue;
                 var shader = mat.shader;
                 if (IsBuiltInObject(shader) && !shader.name.StartsWith("UI/"))
                 {
@@ -281,7 +286,7 @@ namespace Coffee.UIExtensions
             {
                 foreach (var mat in s_TempMaterials)
                 {
-                    if (!mat || !mat.shader) continue;
+                    if (mat == null || mat.shader == null) continue;
                     var shader = mat.shader;
                     if (!s_Shaders.Add(shader)) continue;
 

Packages/src/Icons.meta

@@ -1,8 +0,0 @@
-fileFormatVersion: 2
-guid: 7a55e246f37df405bac88eac692e3a86
-folderAsset: yes
-DefaultImporter:
-  externalObjects: {}
-  userData: 
-  assetBundleName: 
-  assetBundleVariant: 

Packages/src/README.md

@@ -144,7 +144,7 @@ _This package requires **Unity 2018.3 or later**._
 
 #### Install as Embedded Package
 
-1. Download a source code zip file from [Releases](https://github.com/mob-sakai/ParticleEffectForUGUI.git/releases) and extract it.
+1. Download a source code zip file from [Releases](https://github.com/mob-sakai/ParticleEffectForUGUI/releases) and extract it.
 2. Place it in your project's `Packages` directory.  
    ![](https://github.com/mob-sakai/mob-sakai/assets/12690315/0b7484b4-5fca-43b0-a9ef-e5dbd99bcdb4)
 - If you want to fix bugs or add features, install it as an embedded package.
@@ -158,7 +158,7 @@ _This package requires **Unity 2018.3 or later**._
 
 `UIParticle` controls the ParticleSystems that are attached to its own game objects and child game objects.
 
-![](https://github.com/mob-sakai/ParticleEffectForUGUI/assets/12690315/1cf5753b-33fc-4cef-91c3-413c515a954f)
+![](https://github.com/user-attachments/assets/bc9eb783-afce-4102-ac61-aee9ea8d6f2f)
 
 - **Maskable**: Does this graphic allow maskable.
 - **Scale**: Scale the rendering particles. When the `3D` toggle is enabled, 3D scale (x, y, z) is supported.
@@ -180,6 +180,7 @@ _This package requires **Unity 2018.3 or later**._
   - **UIParticle:** UIParticle.scale will be adjusted.
 - **Use Custom View:** Use this if the particles are not displayed correctly due to min/max particle size.
   - **Custom view size:** Change the bake view size.
+- **Time Scale Multiplier:** Time scale multiplier.
 - **Rendering Order**: The ParticleSystem list to be rendered. You can change the order and the materials.
 
 **NOTE:** Press the `Refresh` button to reconstruct the rendering order based on children ParticleSystem's sorting order
@@ -210,7 +211,7 @@ and z-position.
 If you want to mask particles, set a stencil-supported shader (such as `UI/UIAdditive`) to the material for
 ParticleSystem.
 If you use some custom shaders, see
-the [How to Make a Custom Shader to Support Mask/RectMask2D Component](#how-to-make-a-custom-shader-to-support-maskrectmask2d-component)
+the [How to Make a Custom Shader to Support Mask/RectMask2D Component](#how-to-make-a-custom-shader-to-support-mask-and-rectmask2d-component)
 section.
 
 ![](https://user-images.githubusercontent.com/12690315/95017591-3b512700-0695-11eb-864e-04166ea1809a.png)

Packages/src/Runtime/Coffee.UIParticle.R.dll.meta

@@ -0,0 +1,33 @@
+fileFormatVersion: 2
+guid: 4d73b3825bf044d418ae21bb331d3902
+PluginImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  iconMap: {}
+  executionOrder: {}
+  defineConstraints: []
+  isPreloaded: 0
+  isOverridable: 1
+  isExplicitlyReferenced: 0
+  validateReferences: 1
+  platformData:
+  - first:
+      Any: 
+    second:
+      enabled: 1
+      settings: {}
+  - first:
+      Editor: Editor
+    second:
+      enabled: 0
+      settings:
+        DefaultValueInitialized: true
+  - first:
+      Windows Store Apps: WindowsStoreApps
+    second:
+      enabled: 0
+      settings:
+        CPU: AnyCPU
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Packages/src/Runtime/Internal/Extensions/ComponentExtensions.cs

@@ -38,7 +38,7 @@ namespace Coffee.UIParticleInternal
         private static void GetComponentsInChildren_Internal<T>(this Component self, List<T> results, int depth)
             where T : Component
         {
-            if (!self || results == null || depth < 0) return;
+            if (self == null || results == null || depth < 0) return;
 
             var tr = self.transform;
             if (tr.TryGetComponent<T>(out var t))
@@ -59,7 +59,7 @@ namespace Coffee.UIParticleInternal
         /// </summary>
         public static T GetOrAddComponent<T>(this Component self) where T : Component
         {
-            if (!self) return null;
+            if (self == null) return null;
             return self.TryGetComponent<T>(out var component)
                 ? component
                 : self.gameObject.AddComponent<T>();
@@ -166,7 +166,7 @@ namespace Coffee.UIParticleInternal
 #if !UNITY_2021_2_OR_NEWER && !UNITY_2020_3_45 && !UNITY_2020_3_46 && !UNITY_2020_3_47 && !UNITY_2020_3_48
         public static T GetComponentInParent<T>(this Component self, bool includeInactive) where T : Component
         {
-            if (!self) return null;
+            if (self == null) return null;
             if (!includeInactive) return self.GetComponentInParent<T>();
 
             var current = self.transform;
@@ -184,9 +184,9 @@ namespace Coffee.UIParticleInternal
         /// <summary>
         /// Verify whether it can be converted to the specified component.
         /// </summary>
-        internal static bool CanConvertTo<T>(this Object context) where T : MonoBehaviour
+            internal static bool CanConvertTo<T>(this Object context) where T : MonoBehaviour
         {
-            return context && context.GetType() != typeof(T);
+            return context != null && context.GetType() != typeof(T);
         }
 
         /// <summary>
@@ -204,7 +204,7 @@ namespace Coffee.UIParticleInternal
             target.enabled = false;
 
             // Find MonoScript of the specified component.
-            foreach (var script in Resources.FindObjectsOfTypeAll<MonoScript>())
+            foreach (var script in MonoImporter.GetAllRuntimeMonoScripts())
             {
                 if (script.GetClass() != typeof(T))
                 {

Packages/src/Runtime/Internal/Extensions/SpriteExtensions.cs

@@ -32,10 +32,10 @@ namespace Coffee.UIParticleInternal
         /// </summary>
         public static Texture2D GetActualTexture(this Sprite self)
         {
-            if (!self) return null;
+            if (self == null) return null;
 
             var ret = s_GetActiveAtlasTextureMethod(self);
-            return ret ? ret : self.texture;
+            return ret != null ? ret : self.texture;
         }
 
         /// <summary>
@@ -43,7 +43,7 @@ namespace Coffee.UIParticleInternal
         /// </summary>
         public static SpriteAtlas GetActiveAtlas(this Sprite self)
         {
-            if (!self) return null;
+            if (self == null) return null;
 
             return s_GetActiveAtlasMethod(self);
         }
@@ -53,7 +53,7 @@ namespace Coffee.UIParticleInternal
         /// </summary>
         internal static Texture2D GetActualTexture(this Sprite self)
         {
-            return self ? self.texture : null;
+            return self != null ? self.texture : null;
         }
 #endif
     }

Packages/src/Runtime/Internal/ProjectSettings/PreloadedProjectSettings.cs

@@ -37,7 +37,7 @@ namespace Coffee.UIParticleInternal
             foreach (var t in TypeCache.GetTypesDerivedFrom(typeof(PreloadedProjectSettings<>)))
             {
                 var defaultSettings = GetDefaultSettings(t);
-                if (!defaultSettings)
+                if (defaultSettings == null)
                 {
                     // When create a new instance, automatically set it as default settings.
                     defaultSettings = CreateInstance(t) as PreloadedProjectSettings;
@@ -48,7 +48,7 @@ namespace Coffee.UIParticleInternal
                     SetDefaultSettings(defaultSettings);
                 }
 
-                if (defaultSettings)
+                if (defaultSettings != null)
                 {
                     defaultSettings.OnInitialize();
                 }
@@ -66,7 +66,7 @@ namespace Coffee.UIParticleInternal
         private static Object[] GetPreloadedSettings(Type type)
         {
             return PlayerSettings.GetPreloadedAssets()
-                .Where(x => x && x.GetType() == type)
+                .Where(x => x != null && x.GetType() == type)
                 .ToArray();
         }
 
@@ -76,12 +76,12 @@ namespace Coffee.UIParticleInternal
                    ?? AssetDatabase.FindAssets($"t:{nameof(PreloadedProjectSettings)}")
                        .Select(AssetDatabase.GUIDToAssetPath)
                        .Select(AssetDatabase.LoadAssetAtPath<PreloadedProjectSettings>)
-                       .FirstOrDefault(x => x && x.GetType() == type);
+                       .FirstOrDefault(x => x != null && x.GetType() == type);
         }
 
         protected static void SetDefaultSettings(PreloadedProjectSettings asset)
         {
-            if (!asset) return;
+            if (asset == null) return;
 
             var type = asset.GetType();
             if (string.IsNullOrEmpty(AssetDatabase.GetAssetPath(asset)))
@@ -103,7 +103,7 @@ namespace Coffee.UIParticleInternal
             var preloadedAssets = PlayerSettings.GetPreloadedAssets();
             var projectSettings = GetPreloadedSettings(type);
             PlayerSettings.SetPreloadedAssets(preloadedAssets
-                .Where(x => x)
+                .Where(x => x != null)
                 .Except(projectSettings.Except(new[] { asset }))
                 .Append(asset)
                 .Distinct()
@@ -133,17 +133,19 @@ namespace Coffee.UIParticleInternal
 #if UNITY_EDITOR
         private string _jsonText;
 
+        public static bool hasInstance => s_Instance != null;
+
         public static T instance
         {
             get
             {
-                if (s_Instance) return s_Instance;
+                if (s_Instance != null) return s_Instance;
 
                 s_Instance = GetDefaultSettings(typeof(T)) as T;
-                if (s_Instance) return s_Instance;
+                if (s_Instance != null) return s_Instance;
 
                 s_Instance = CreateInstance<T>();
-                if (!s_Instance)
+                if (s_Instance == null)
                 {
                     s_Instance = null;
                     return s_Instance;
@@ -172,7 +174,7 @@ namespace Coffee.UIParticleInternal
             }
         }
 #else
-        public static T instance => s_Instance ? s_Instance : s_Instance = CreateInstance<T>();
+    public static T instance => s_Instance != null ? s_Instance : s_Instance = CreateInstance<T>();
 #endif
 
         /// <summary>
@@ -181,7 +183,7 @@ namespace Coffee.UIParticleInternal
         protected virtual void OnEnable()
         {
 #if UNITY_EDITOR
-            var isDefaultSettings = !s_Instance || s_Instance == this || GetDefaultSettings(typeof(T)) == this;
+            var isDefaultSettings = s_Instance == null || s_Instance == this || GetDefaultSettings(typeof(T)) == this;
             if (!isDefaultSettings)
             {
                 DestroyImmediate(this, true);
@@ -191,7 +193,7 @@ namespace Coffee.UIParticleInternal
             EditorApplication.playModeStateChanged += OnPlayModeStateChanged;
 #endif
 
-            if (s_Instance) return;
+            if (s_Instance != null) return;
             s_Instance = this as T;
         }
 
@@ -220,7 +222,7 @@ namespace Coffee.UIParticleInternal
 
             public override void OnGUI(string searchContext)
             {
-                if (!_target)
+                if (_target == null)
                 {
                     if (_editor)
                     {

Packages/src/Runtime/Internal/Utilities/Logging.cs

@@ -48,7 +48,7 @@ namespace Coffee.UIParticleInternal
         public static void LogIf(bool enable, object tag, object message, Object context = null)
         {
             if (!enable) return;
-            Log_Internal(LogType.Log, tag, message, context ? context : tag as Object);
+            Log_Internal(LogType.Log, tag, message, context != null ? context : tag as Object);
         }
 
 #if !ENABLE_COFFEE_LOGGER
@@ -56,7 +56,7 @@ namespace Coffee.UIParticleInternal
 #endif
         public static void Log(object tag, object message, Object context = null)
         {
-            Log_Internal(LogType.Log, tag, message, context ? context : tag as Object);
+            Log_Internal(LogType.Log, tag, message, context != null ? context : tag as Object);
         }
 
 #if !ENABLE_COFFEE_LOGGER
@@ -64,13 +64,13 @@ namespace Coffee.UIParticleInternal
 #endif
         public static void LogWarning(object tag, object message, Object context = null)
         {
-            Log_Internal(LogType.Warning, tag, message, context ? context : tag as Object);
+            Log_Internal(LogType.Warning, tag, message, context != null ? context : tag as Object);
         }
 
         public static void LogError(object tag, object message, Object context = null)
         {
 #if ENABLE_COFFEE_LOGGER
-            Log_Internal(LogType.Error, tag, message, context ? context : tag as Object);
+            Log_Internal(LogType.Error, tag, message, context != null ? context : tag as Object);
 #else
             Debug.LogError($"{tag}: {message}", context);
 #endif

Packages/src/Runtime/Internal/Utilities/MaterialRepository.cs

@@ -15,7 +15,7 @@ namespace Coffee.UIParticleInternal
 
 #if UNITY_EDITOR
         [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
-        private static void Clear()
+        public static void Clear()
         {
             s_Repository.Clear();
         }

Packages/src/Runtime/Internal/Utilities/Misc.cs

@@ -3,11 +3,16 @@ using System.Diagnostics;
 using UnityEditor;
 using UnityEngine;
 using Object = UnityEngine.Object;
-#if UNITY_EDITOR && UNITY_2021_2_OR_NEWER
+#if UNITY_EDITOR
+using System.IO;
+using System.Linq;
+using System.Reflection;
+#if UNITY_2021_2_OR_NEWER
 using UnityEditor.SceneManagement;
-#elif UNITY_EDITOR
+#else
 using UnityEditor.Experimental.SceneManagement;
 #endif
+#endif
 
 namespace Coffee.UIParticleInternal
 {
@@ -24,7 +29,7 @@ namespace Coffee.UIParticleInternal
 
         public static void Destroy(Object obj)
         {
-            if (!obj) return;
+            if (obj == null) return;
 #if UNITY_EDITOR
             if (!Application.isPlaying)
             {
@@ -39,7 +44,7 @@ namespace Coffee.UIParticleInternal
 
         public static void DestroyImmediate(Object obj)
         {
-            if (!obj) return;
+            if (obj == null) return;
 #if UNITY_EDITOR
             if (Application.isEditor)
             {
@@ -56,7 +61,7 @@ namespace Coffee.UIParticleInternal
         public static void SetDirty(Object obj)
         {
 #if UNITY_EDITOR
-            if (!obj) return;
+            if (obj == null) return;
             EditorUtility.SetDirty(obj);
 #endif
         }
@@ -69,6 +74,59 @@ namespace Coffee.UIParticleInternal
 
             return prefabStage.prefabContentsRoot.GetComponentsInChildren<T>(true);
         }
+
+        public static bool isBatchOrBuilding => Application.isBatchMode || BuildPipeline.isBuildingPlayer;
+#endif
+
+        [Conditional("UNITY_EDITOR")]
+        public static void QueuePlayerLoopUpdate()
+        {
+#if UNITY_EDITOR
+            if (!EditorApplication.isPlaying)
+            {
+                EditorApplication.QueuePlayerLoopUpdate();
+            }
+#endif
+        }
+    }
+
+#if !UNITY_2021_2_OR_NEWER
+    [AttributeUsage(AttributeTargets.Class)]
+    [Conditional("UNITY_EDITOR")]
+    internal class IconAttribute : Attribute
+    {
+        private readonly string _path;
+
+        public IconAttribute(string path)
+        {
+            _path = path;
+        }
+
+#if UNITY_EDITOR
+        private static Action<Object, Texture2D> s_SetIconForObject = typeof(EditorGUIUtility)
+            .GetMethod("SetIconForObject", BindingFlags.Static | BindingFlags.NonPublic)
+            .CreateDelegate(typeof(Action<Object, Texture2D>), null) as Action<Object, Texture2D>;
+
+        [InitializeOnLoadMethod]
+        private static void InitializeOnLoadMethod()
+        {
+            if (Misc.isBatchOrBuilding) return;
+
+            var types = TypeCache.GetTypesWithAttribute<IconAttribute>();
+            var scripts = MonoImporter.GetAllRuntimeMonoScripts();
+            foreach (var type in types)
+            {
+                var script = scripts.FirstOrDefault(x => x.GetClass() == type);
+                if (script == null) continue;
+
+                var path = type.GetCustomAttribute<IconAttribute>()?._path;
+                var icon = AssetDatabase.LoadAssetAtPath<Texture2D>(path);
+                if (icon == null) continue;
+
+                s_SetIconForObject(script, icon);
+            }
+        }
 #endif
     }
+#endif
 }

Packages/src/Runtime/Internal/Utilities/ObjectRepository.cs

@@ -90,7 +90,7 @@ namespace Coffee.UIParticleInternal
             Profiler.BeginSample("(COF)[ObjectRepository] GetFromCache");
             if (_cache.TryGetValue(hash, out var entry))
             {
-                if (!entry.storedObject)
+                if (entry.storedObject == null)
                 {
                     Release(ref entry.storedObject);
                     Profiler.EndSample();
@@ -116,7 +116,7 @@ namespace Coffee.UIParticleInternal
 
         private void Add(Hash128 hash, ref T obj, T newObject)
         {
-            if (!newObject)
+            if (newObject == null)
             {
                 Release(ref obj);
                 obj = newObject;
@@ -151,7 +151,7 @@ namespace Coffee.UIParticleInternal
                 && _cache.TryGetValue(hash, out var entry))
             {
                 entry.reference--;
-                if (entry.reference <= 0 || !entry.storedObject)
+                if (entry.reference <= 0 || entry.storedObject == null)
                 {
                     Remove(entry);
                 }
@@ -192,7 +192,7 @@ namespace Coffee.UIParticleInternal
             public void Release(Action<T> onRelease)
             {
                 reference = 0;
-                if (storedObject)
+                if (storedObject != null)
                 {
                     onRelease?.Invoke(storedObject);
                 }

Packages/src/Runtime/UIParticle.cs

@@ -9,6 +9,7 @@ using UnityEngine.UI;
 using Random = UnityEngine.Random;
 
 [assembly: InternalsVisibleTo("Coffee.UIParticle.Editor")]
+[assembly: InternalsVisibleTo("Coffee.UIParticle.Editor.Tests")]
 [assembly: InternalsVisibleTo("Coffee.UIParticle.PerformanceDemo")]
 [assembly: InternalsVisibleTo("Coffee.UIParticle.Demo")]
 
@@ -17,6 +18,7 @@ namespace Coffee.UIExtensions
     /// <summary>
     /// Render maskable and sortable particle effect ,without Camera, RenderTexture or Canvas.
     /// </summary>
+    [Icon("Packages/com.coffee.ui-particle/Editor/UIParticleIcon.png")]
     [ExecuteAlways]
     [RequireComponent(typeof(RectTransform))]
     [RequireComponent(typeof(CanvasRenderer))]
@@ -119,6 +121,10 @@ namespace Coffee.UIExtensions
                  "Change the bake view size.")]
         private float m_CustomViewSize = 10;
 
+        [SerializeField]
+        [Tooltip("Time scale multiplier.")]
+        private float m_TimeScaleMultiplier = 1;
+
         private readonly List<UIParticleRenderer> _renderers = new List<UIParticleRenderer>();
         private Camera _bakeCamera;
         private int _groupId;
@@ -257,6 +263,15 @@ namespace Coffee.UIExtensions
             set => m_CustomViewSize = Mathf.Max(0.1f, value);
         }
 
+        /// <summary>
+        /// Time scale multiplier.
+        /// </summary>
+        public float timeScaleMultiplier
+        {
+            get => m_TimeScaleMultiplier;
+            set => m_TimeScaleMultiplier = value;
+        }
+
         internal bool useMeshSharing => m_MeshSharing != MeshSharing.None;
 
         internal bool isPrimary =>
@@ -456,7 +471,7 @@ namespace Coffee.UIExtensions
             for (var i = 0; i < _renderers.Count; i++)
             {
                 var r = _renderers[i];
-                if (!r || !r.material) continue;
+                if (r == null || r.material == null) continue;
                 result.Add(r.material);
             }
         }
@@ -474,7 +489,7 @@ namespace Coffee.UIExtensions
         /// </summary>
         public void SetParticleSystemInstance(GameObject instance, bool destroyOldParticles)
         {
-            if (!instance) return;
+            if (instance == null) return;
 
             var childCount = transform.childCount;
             for (var i = 0; i < childCount; i++)
@@ -503,7 +518,7 @@ namespace Coffee.UIExtensions
         /// </summary>
         public void SetParticleSystemPrefab(GameObject prefab)
         {
-            if (!prefab) return;
+            if (prefab == null) return;
 
             SetParticleSystemInstance(Instantiate(prefab.gameObject), true);
         }
@@ -523,12 +538,14 @@ namespace Coffee.UIExtensions
         /// </summary>
         private void RefreshParticles(GameObject root)
         {
-            if (!root) return;
+            if (root == null) return;
             root.GetComponentsInChildren(true, particles);
             for (var i = particles.Count - 1; 0 <= i; i--)
             {
                 var ps = particles[i];
-                if (!ps || ps.GetComponentInParent<UIParticle>(true) != this)
+                if (!ps
+                    || ps.gameObject.CompareTag("EditorOnly") // Ignore "EditorOnly" tagged ParticleSystems.
+                    || ps.GetComponentInParent<UIParticle>(true) != this) // Ignore ParticleSystems that are not under this UIParticle.
                 {
                     particles.RemoveAt(i);
                 }
@@ -576,13 +593,15 @@ namespace Coffee.UIExtensions
             for (var i = 0; i < particleSystems.Count; i++)
             {
                 var ps = particleSystems[i];
-                if (!ps) continue;
-                GetRenderer(j++).Set(this, ps, false);
+                if (ps == null) continue;
+
+                var mainEmitter = ps.GetMainEmitter(particleSystems);
+                GetRenderer(j++).Set(this, ps, false, mainEmitter);
 
                 // If the trail is enabled, set it additionally.
                 if (ps.trails.enabled)
                 {
-                    GetRenderer(j++).Set(this, ps, true);
+                    GetRenderer(j++).Set(this, ps, true, mainEmitter);
                 }
             }
         }
@@ -625,7 +644,7 @@ namespace Coffee.UIExtensions
             for (var i = 0; i < _renderers.Count; i++)
             {
                 var r = _renderers[i];
-                if (r) continue;
+                if (r != null) continue;
 
                 RefreshParticles(particles);
                 break;
@@ -635,7 +654,7 @@ namespace Coffee.UIExtensions
             for (var i = 0; i < _renderers.Count; i++)
             {
                 var r = _renderers[i];
-                if (!r) continue;
+                if (r == null) continue;
 
                 r.UpdateMesh(bakeCamera);
             }
@@ -664,7 +683,7 @@ namespace Coffee.UIExtensions
             for (var i = 0; i < _renderers.Count; i++)
             {
                 var r = _renderers[i];
-                if (!r) continue;
+                if (r == null) continue;
                 r.maskable = maskable;
                 r.SetMaterialDirty();
             }
@@ -677,7 +696,7 @@ namespace Coffee.UIExtensions
                 _renderers.Add(UIParticleRenderer.AddRenderer(this, index));
             }
 
-            if (!_renderers[index])
+            if (_renderers[index] == null)
             {
                 _renderers[index] = UIParticleRenderer.AddRenderer(this, index);
             }
@@ -687,13 +706,13 @@ namespace Coffee.UIExtensions
 
         private Camera GetBakeCamera()
         {
-            if (!canvas) return Camera.main;
+            if (canvas == null) return Camera.main;
             if (!useCustomView && canvas.renderMode != RenderMode.ScreenSpaceOverlay && canvas.rootCanvas.worldCamera)
             {
                 return canvas.rootCanvas.worldCamera;
             }
 
-            if (_bakeCamera)
+            if (_bakeCamera != null)
             {
                 _bakeCamera.orthographicSize = useCustomView ? customViewSize : 10;
                 return _bakeCamera;
@@ -712,7 +731,7 @@ namespace Coffee.UIExtensions
             }
 
             // Create baking camera.
-            if (!_bakeCamera)
+            if (_bakeCamera == null)
             {
                 var go = new GameObject("[generated] UIParticle BakingCamera");
                 go.SetActive(false);

Packages/src/Runtime/UIParticle.cs.meta

@@ -5,7 +5,7 @@ MonoImporter:
   serializedVersion: 2
   defaultReferences: []
   executionOrder: 0
-  icon: {fileID: 2800000, guid: 5f0675613942149309588d556e33d990, type: 3}
+  icon: {instanceID: 0}
   userData: 
   assetBundleName: 
   assetBundleVariant: 

Packages/src/Runtime/UIParticleAttractor.cs

@@ -208,7 +208,7 @@ namespace Coffee.UIExtensions
 
         private Vector3 GetDestinationPosition(UIParticle uiParticle, ParticleSystem particleSystem)
         {
-            var isUI = uiParticle && uiParticle.enabled;
+            var isUI = uiParticle != null && uiParticle.enabled;
             var psPos = particleSystem.transform.position;
             var attractorPos = transform.position;
             var dstPos = attractorPos;

Packages/src/Runtime/UIParticleRenderer.cs

@@ -15,6 +15,7 @@ using UnityEngine.UI;
 
 namespace Coffee.UIExtensions
 {
+    [Icon("Packages/com.coffee.ui-particle/Editor/UIParticleIcon.png")]
     [ExecuteAlways]
     [RequireComponent(typeof(RectTransform))]
     [RequireComponent(typeof(CanvasRenderer))]
@@ -40,6 +41,7 @@ namespace Coffee.UIExtensions
         private Vector2Int _prevScreenSize;
         private bool _preWarm;
         private ParticleSystemRenderer _renderer;
+        private ParticleSystem _mainEmitter;
 
         public override Texture mainTexture => _isTrail ? null : _particleSystem.GetTextureForSprite();
 
@@ -53,7 +55,7 @@ namespace Coffee.UIExtensions
                 s_Corners[1] = transform.TransformPoint(_lastBounds.min.x, _lastBounds.max.y, 0);
                 s_Corners[2] = transform.TransformPoint(_lastBounds.max.x, _lastBounds.max.y, 0);
                 s_Corners[3] = transform.TransformPoint(_lastBounds.max.x, _lastBounds.min.y, 0);
-                if (canvas)
+                if (canvas != null)
                 {
                     var worldToLocalMatrix = canvas.rootCanvas.transform.worldToLocalMatrix;
                     for (var i = 0; i < 4; ++i)
@@ -93,7 +95,7 @@ namespace Coffee.UIExtensions
         {
             get
             {
-                if (!_materialForRendering)
+                if (_materialForRendering == null)
                 {
                     _materialForRendering = base.materialForRendering;
                 }
@@ -104,7 +106,7 @@ namespace Coffee.UIExtensions
 
         public void Reset(int index = -1)
         {
-            if (_renderer)
+            if (_renderer != null)
             {
                 _renderer.enabled = true;
             }
@@ -112,13 +114,14 @@ namespace Coffee.UIExtensions
             _parent = null;
             _particleSystem = null;
             _renderer = null;
+            _mainEmitter = null;
             if (0 <= index)
             {
                 _index = index;
             }
 
             //_emitter = null;
-            if (this && isActiveAndEnabled)
+            if (isActiveAndEnabled)
             {
                 material = null;
                 canvasRenderer.Clear();
@@ -137,7 +140,7 @@ namespace Coffee.UIExtensions
             base.OnEnable();
 
             hideFlags = UIParticleProjectSettings.globalHideFlags;
-            if (!s_CombineInstances[0].mesh)
+            if (s_CombineInstances[0].mesh == null)
             {
                 s_CombineInstances[0].mesh = new Mesh
                 {
@@ -223,7 +226,7 @@ namespace Coffee.UIExtensions
             return _modifiedMaterial;
         }
 
-        public void Set(UIParticle parent, ParticleSystem ps, bool isTrail)
+        public void Set(UIParticle parent, ParticleSystem ps, bool isTrail, ParticleSystem mainEmitter)
         {
             _parent = parent;
             maskable = parent.maskable;
@@ -246,10 +249,7 @@ namespace Coffee.UIExtensions
 
             ps.TryGetComponent(out _renderer);
             _renderer.enabled = false;
-
-            //_emitter = emitter;
             _isTrail = isTrail;
-
             _renderer.GetSharedMaterials(s_Materials);
             material = s_Materials[isTrail ? 1 : 0];
             s_Materials.Clear();
@@ -266,6 +266,7 @@ namespace Coffee.UIExtensions
             _prevScreenSize = new Vector2Int(Screen.width, Screen.height);
             _prevCanvasScale = canvas ? canvas.scaleFactor : 1f;
             _delay = true;
+            _mainEmitter = mainEmitter;
 
             canvasRenderer.SetTexture(null);
 
@@ -282,10 +283,6 @@ namespace Coffee.UIExtensions
                 || !transform.lossyScale.GetScaled(_parent.scale3DForCalc).IsVisible() // Scale is not visible.
                 || (!_particleSystem.IsAlive() && !_particleSystem.isPlaying) // No particle.
                 || (_isTrail && !_particleSystem.trails.enabled) // Trail, but it is not enabled.
-#if UNITY_2018_3_OR_NEWER
-                || canvasRenderer.GetInheritedAlpha() <
-                0.01f // #102: Do not bake particle system to mesh when the alpha is zero.
-#endif
             )
             {
                 Profiler.BeginSample("[UIParticleRenderer] Clear Mesh");
@@ -297,13 +294,31 @@ namespace Coffee.UIExtensions
                 return;
             }
 
+            // Reset custom data.
+            // var customData = _particleSystem.customData;
+            // if (!customData.enabled || customData.GetMode(ParticleSystemCustomData.Custom1) == ParticleSystemCustomDataMode.Disabled)
+            // {
+            //     customData.SetVector(ParticleSystemCustomData.Custom1, 0, 0);
+            //     customData.SetVector(ParticleSystemCustomData.Custom1, 1, 0);
+            //     customData.SetVector(ParticleSystemCustomData.Custom1, 2, 0);
+            //     customData.SetVector(ParticleSystemCustomData.Custom1, 3, 0);
+            // }
+            //
+            // if (!customData.enabled || customData.GetMode(ParticleSystemCustomData.Custom2) == ParticleSystemCustomDataMode.Disabled)
+            // {
+            //     customData.SetVector(ParticleSystemCustomData.Custom2, 0, 0);
+            //     customData.SetVector(ParticleSystemCustomData.Custom2, 1, 0);
+            //     customData.SetVector(ParticleSystemCustomData.Custom2, 2, 0);
+            //     customData.SetVector(ParticleSystemCustomData.Custom2, 3, 0);
+            // }
+
             var main = _particleSystem.main;
             var scale = GetWorldScale();
             var psPos = _particleSystem.transform.position;
 
             // Simulate particles.
             Profiler.BeginSample("[UIParticle] Bake Mesh > Simulate Particles");
-            if (!_isTrail && _parent.canSimulate)
+            if (!_isTrail && _parent.canSimulate && !_mainEmitter)
             {
 #if UNITY_EDITOR
                 if (!Application.isPlaying)
@@ -314,6 +329,13 @@ namespace Coffee.UIExtensions
 #endif
                 {
                     ResolveResolutionChange(psPos, scale);
+
+                    // fix: second and subsequent bursts not displayed when world simulation and non-looping. (#326)
+                    if (!_particleSystem.IsLocalSpace() && !main.loop && _particleSystem.time == 0)
+                    {
+                        _delay = true;
+                    }
+
                     Simulate(scale, _parent.isPaused || _delay);
 
                     if (_delay && !_parent.isPaused)
@@ -548,6 +570,24 @@ namespace Coffee.UIExtensions
                                * Matrix4x4.Scale(scale)
                                * Matrix4x4.Translate(-psPos);
                     }
+
+                    if (_mainEmitter)
+                    {
+                        if (_mainEmitter.IsLocalSpace())
+                        {
+                            return Matrix4x4.Translate(psPos)
+                                   * Matrix4x4.Scale(scale)
+                                   * Matrix4x4.Translate(-psPos);
+                        }
+                        else
+                        {
+                            psPos = _particleSystem.transform.position - _mainEmitter.transform.position;
+                            return Matrix4x4.Translate(psPos)
+                                   * Matrix4x4.Scale(scale)
+                                   * Matrix4x4.Translate(-psPos);
+                        }
+                    }
+
                     return Matrix4x4.Scale(scale);
                 case ParticleSystemSimulationSpace.Custom:
                     return Matrix4x4.Translate(_particleSystem.main.customSimulationSpace.position.GetScaled(scale))
@@ -610,6 +650,7 @@ namespace Coffee.UIExtensions
                 : main.useUnscaledTime
                     ? Time.unscaledDeltaTime
                     : Time.deltaTime;
+            deltaTime *= _parent.timeScaleMultiplier;
 
             // Pre-warm:
             if (0 < deltaTime && _preWarm)
@@ -690,7 +731,7 @@ namespace Coffee.UIExtensions
             if (s_Mpb.isEmpty) return;
 
             // #41: Copy the value from MaterialPropertyBlock to CanvasRenderer
-            if (!materialForRendering) return;
+            if (materialForRendering == null) return;
 
             for (var i = 0; i < _parent.m_AnimatableProperties.Length; i++)
             {

Packages/src/Runtime/UIParticleRenderer.cs.meta

@@ -5,7 +5,7 @@ MonoImporter:
   serializedVersion: 2
   defaultReferences: []
   executionOrder: 0
-  icon: {fileID: 2800000, guid: 5f0675613942149309588d556e33d990, type: 3}
+  icon: {instanceID: 0}
   userData: 
   assetBundleName: 
   assetBundleVariant: 

Packages/src/Runtime/UIParticleUpdater.cs

@@ -16,37 +16,50 @@ namespace Coffee.UIExtensions
 
         public static void Register(UIParticle particle)
         {
-            if (!particle) return;
+            if (particle == null) return;
             s_ActiveParticles.Add(particle);
         }
 
         public static void Unregister(UIParticle particle)
         {
-            if (!particle) return;
+            if (particle == null) return;
             s_ActiveParticles.Remove(particle);
         }
 
         public static void Register(UIParticleAttractor attractor)
         {
-            if (!attractor) return;
+            if (attractor == null) return;
             s_ActiveAttractors.Add(attractor);
         }
 
         public static void Unregister(UIParticleAttractor attractor)
         {
-            if (!attractor) return;
+            if (attractor == null) return;
             s_ActiveAttractors.Remove(attractor);
         }
 
 #if UNITY_EDITOR
         [InitializeOnLoadMethod]
+        private static void InitializeOnLoad()
+        {
+            UIExtraCallbacks.onAfterCanvasRebuild += Refresh;
+
+            EditorApplication.playModeStateChanged += state =>
+            {
+                UIExtraCallbacks.onAfterCanvasRebuild -= Refresh;
+                if (state == PlayModeStateChange.EnteredEditMode || state == PlayModeStateChange.EnteredPlayMode)
+                {
+                    UIExtraCallbacks.onAfterCanvasRebuild += Refresh;
+                }
+            };
+        }
 #else
         [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.BeforeSceneLoad)]
-#endif
         private static void InitializeOnLoad()
         {
             UIExtraCallbacks.onAfterCanvasRebuild += Refresh;
         }
+#endif
 
         private static void Refresh()
         {
@@ -58,7 +71,7 @@ namespace Coffee.UIExtensions
             for (var i = 0; i < s_ActiveParticles.Count; i++)
             {
                 var uip = s_ActiveParticles[i];
-                if (!uip || !uip.canvas || !uip.isPrimary || !s_UpdatedGroupIds.Add(uip.groupId)) continue;
+                if (uip == null || uip.canvas == null || !uip.isPrimary || !s_UpdatedGroupIds.Add(uip.groupId)) continue;
 
                 uip.UpdateTransformScale();
                 uip.UpdateRenderers();
@@ -68,7 +81,7 @@ namespace Coffee.UIExtensions
             for (var i = 0; i < s_ActiveParticles.Count; i++)
             {
                 var uip = s_ActiveParticles[i];
-                if (!uip || !uip.canvas) continue;
+                if (uip == null || uip.canvas == null) continue;
 
                 uip.UpdateTransformScale();
 
@@ -112,7 +125,7 @@ namespace Coffee.UIExtensions
                 var uip = s_ActiveParticles[i];
                 if (!uip.useMeshSharing || uip.groupId != groupId) continue;
                 if (uip.isPrimary) return uip;
-                if (!primary && uip.canSimulate) primary = uip;
+                if (primary == null && uip.canSimulate) primary = uip;
             }
 
             return primary;

Packages/src/Runtime/Utilities/ParticleSystemExtensions.cs

@@ -13,11 +13,7 @@ namespace Coffee.UIParticleInternal
         {
             if (s_TmpParticles.Length < size)
             {
-                while (s_TmpParticles.Length < size)
-                {
-                    size = Mathf.NextPowerOfTwo(size);
-                }
-
+                size = Mathf.NextPowerOfTwo(size);
                 s_TmpParticles = new ParticleSystem.Particle[size];
             }
 
@@ -88,11 +84,11 @@ namespace Coffee.UIParticleInternal
                 var bRenderer = b.GetComponent<ParticleSystemRenderer>();
 
                 // Render queue: ascending
-                var aMat = aRenderer.sharedMaterial ? aRenderer.sharedMaterial : aRenderer.trailMaterial;
-                var bMat = bRenderer.sharedMaterial ? bRenderer.sharedMaterial : bRenderer.trailMaterial;
-                if (!aMat && !bMat) return 0;
-                if (!aMat) return -1;
-                if (!bMat) return 1;
+                var aMat = aRenderer.sharedMaterial != null ? aRenderer.sharedMaterial : aRenderer.trailMaterial;
+                var bMat = bRenderer.sharedMaterial != null ? bRenderer.sharedMaterial : bRenderer.trailMaterial;
+                if (aMat == null && bMat == null) return 0;
+                if (aMat == null) return -1;
+                if (bMat == null) return 1;
 
                 if (sortByMaterial)
                 {
@@ -146,7 +142,7 @@ namespace Coffee.UIParticleInternal
 
         public static Texture2D GetTextureForSprite(this ParticleSystem self)
         {
-            if (!self) return null;
+            if (self == null) return null;
 
             // Get sprite's texture.
             var tsaModule = self.textureSheetAnimation;
@@ -155,7 +151,7 @@ namespace Coffee.UIParticleInternal
             for (var i = 0; i < tsaModule.spriteCount; i++)
             {
                 var sprite = tsaModule.GetSprite(i);
-                if (!sprite) continue;
+                if (sprite == null) continue;
 
                 return sprite.GetActualTexture();
             }
@@ -167,9 +163,38 @@ namespace Coffee.UIParticleInternal
         {
             foreach (var p in self)
             {
-                if (!p) continue;
+                if (p == null) continue;
                 action.Invoke(p);
             }
         }
+
+        public static ParticleSystem GetMainEmitter(this ParticleSystem self, List<ParticleSystem> list)
+        {
+            if (self == null || list == null || list.Count == 0) return null;
+
+            for (var i = 0; i < list.Count; i++)
+            {
+                var parent = list[i];
+                if (parent != self && IsSubEmitterOf(self, parent)) return parent;
+            }
+
+            return null;
+        }
+
+        public static bool IsSubEmitterOf(this ParticleSystem self, ParticleSystem parent)
+        {
+            if (self == null || parent == null) return false;
+
+            var subEmitters = parent.subEmitters;
+            if (!subEmitters.enabled) return false; // No sub emitters.
+
+            var count = subEmitters.subEmittersCount;
+            for (var i = 0; i < count; i++)
+            {
+                if (subEmitters.GetSubEmitterSystem(i) == self) return true;
+            }
+
+            return false;
+        }
     }
 }

Packages/src/Samples~/Demo/Scripts/CopyItemOnStart.cs

@@ -15,7 +15,7 @@ namespace Coffee.UIExtensions.Demo
 
         private void Start()
         {
-            if (!m_Origin) return;
+            if (m_Origin == null) return;
             m_Origin.SetActive(false);
 
             var parent = m_Origin.transform.parent;

Packages/src/Samples~/Demo/Scripts/UIElementDragger.cs

@@ -42,7 +42,7 @@ public class UIElementDragger : MonoBehaviour, IBeginDragHandler, IDragHandler,
                 break;
             case Target.Custom:
                 _rectTransform.localPosition += delta;
-                if (m_CustomTarget)
+                if (m_CustomTarget != null)
                 {
                     if (m_UseCanvasScale)
                     {

Packages/src/package.json

@@ -2,7 +2,7 @@
   "name": "com.coffee.ui-particle",
   "displayName": "UI Particle",
   "description": "This package provides a component to render particle effects for uGUI.\nThe particle rendering is maskable and sortable, without the need for an extra Camera, RenderTexture, or Canvas.",
-  "version": "4.10.5",
+  "version": "4.12.1",
   "unity": "2018.2",
   "license": "MIT",
   "repository": {

ProjectSettings/MinimalResourceSettings.json

@@ -0,0 +1,11 @@
+{
+    "MonoBehaviour": {
+        "m_Enabled": true,
+        "m_EditorHideFlags": 0,
+        "m_Name": "",
+        "m_EditorClassIdentifier": "",
+        "m_OutputDllPaths": [
+            "Packages/com.coffee.ui-particle/Runtime/Coffee.UIParticle.R.dll"
+        ]
+    }
+}