feat: add 'AutoScaling' option for UIParticle

Transform.lossyScale (=world scale) is automatically set to (1, 1, 1).
It prevents the root-Canvas scale from affecting the hierarchy-scaled ParticleSystem.
This option works in reverse of ’IgnoreCanvasScaler’ option in v3.x.

Scripts/Editor/UIParticleEditor.cs

@@ -52,6 +52,7 @@ namespace Coffee.UIExtensions
         private static readonly GUIContent s_Content3D = new GUIContent("3D");
         private static readonly GUIContent s_ContentRandom = new GUIContent("Random");
         private static readonly GUIContent s_ContentScale = new GUIContent("Scale");
+        private static readonly GUIContent s_ContentAutoScaling = new GUIContent("Auto Scaling", "Transform.lossyScale (=world scale) is automatically set to (1, 1, 1), to prevent the root-Canvas scale from affecting the hierarchy-scaled ParticleSystem.");
         private static SerializedObject s_SerializedObject;
 
 #if !SERIALIZE_FIELD_MASKABLE
@@ -63,6 +64,7 @@ namespace Coffee.UIExtensions
         private SerializedProperty m_GroupId;
         private SerializedProperty m_GroupMaxId;
         private SerializedProperty m_AbsoluteMode;
+        private SerializedProperty m_IgnoreCanvasScaler;
 
 
         private ReorderableList _ro;
@@ -152,6 +154,7 @@ namespace Coffee.UIExtensions
             m_GroupId = serializedObject.FindProperty("m_GroupId");
             m_GroupMaxId = serializedObject.FindProperty("m_GroupMaxId");
             m_AbsoluteMode = serializedObject.FindProperty("m_AbsoluteMode");
+            m_IgnoreCanvasScaler = serializedObject.FindProperty("m_IgnoreCanvasScaler");
 
             var sp = serializedObject.FindProperty("m_Particles");
             _ro = new ReorderableList(sp.serializedObject, sp, true, true, true, true);
@@ -262,6 +265,18 @@ namespace Coffee.UIExtensions
             // Absolute Mode
             EditorGUILayout.PropertyField(m_AbsoluteMode);
 
+            // Auto Scaling
+            DrawInversedToggle(m_IgnoreCanvasScaler, s_ContentAutoScaling, () =>
+            {
+                foreach (var uip in targets.OfType<UIParticle>())
+                {
+                    if (uip && !uip.autoScaling)
+                    {
+                        uip.transform.localScale = Vector3.one;
+                    }
+                }
+            });
+
             // Target ParticleSystems.
             EditorGUI.BeginChangeCheck();
             EditorGUI.BeginDisabledGroup(targets.OfType<UIParticle>().Any(x => !x.canvas));
@@ -426,6 +441,24 @@ namespace Coffee.UIExtensions
             return showMax;
         }
 
+        private static void DrawInversedToggle(SerializedProperty inversedProperty, GUIContent label, Action onChanged)
+        {
+            EditorGUI.showMixedValue = inversedProperty.hasMultipleDifferentValues;
+            var autoScaling = !inversedProperty.boolValue;
+            EditorGUI.BeginChangeCheck();
+            if (autoScaling != EditorGUILayout.Toggle(label, autoScaling))
+            {
+                inversedProperty.boolValue = autoScaling;
+            }
+
+            if (EditorGUI.EndChangeCheck())
+            {
+                EditorApplication.delayCall += onChanged.Invoke;
+            }
+
+            EditorGUI.showMixedValue = false;
+        }
+
         private static void WindowFunction(UnityEngine.Object target, SceneView sceneView)
         {
             try
@@ -441,6 +474,17 @@ namespace Coffee.UIExtensions
                     EditorGUILayout.PropertyField(s_SerializedObject.FindProperty("m_Enabled"));
                     _xyzMode = DrawFloatOrVector3Field(s_SerializedObject.FindProperty("m_Scale3D"), _xyzMode);
                     EditorGUILayout.PropertyField(s_SerializedObject.FindProperty("m_AbsoluteMode"));
+                    DrawInversedToggle(s_SerializedObject.FindProperty("m_IgnoreCanvasScaler"), s_ContentAutoScaling,
+                        () =>
+                        {
+                            foreach (var uip in s_SerializedObject.targetObjects.OfType<UIParticle>())
+                            {
+                                if (uip && !uip.autoScaling)
+                                {
+                                    uip.transform.localScale = Vector3.one;
+                                }
+                            }
+                        });
                     EditorGUIUtility.labelWidth = labelWidth;
                 }
                 s_SerializedObject.ApplyModifiedProperties();

Scripts/UIParticle.cs

@@ -7,6 +7,7 @@ using System.Runtime.CompilerServices;
 using Coffee.UIParticleExtensions;
 using UnityEngine;
 using UnityEngine.Rendering;
+using UnityEngine.Serialization;
 using UnityEngine.UI;
 
 [assembly: InternalsVisibleTo("Coffee.UIParticle.Editor")]
@@ -59,6 +60,13 @@ namespace Coffee.UIExtensions
         [Tooltip("The particles will be emitted at the ParticleSystem position.\nMove the UIParticle/ParticleSystem to move the particle.")]
         private bool m_AbsoluteMode = false;
 
+        /// <summary>
+        /// This field uses the inverted value as "AutoScaling".
+        /// </summary>
+        [SerializeField]
+        [FormerlySerializedAs("m_IgnoreParent")]
+        private bool m_IgnoreCanvasScaler = false;
+
         private List<UIParticleRenderer> m_Renderers = new List<UIParticleRenderer>();
 
 #if !SERIALIZE_FIELD_MASKABLE
@@ -128,6 +136,17 @@ namespace Coffee.UIExtensions
             set { m_AbsoluteMode = value; }
         }
 
+        public bool autoScaling
+        {
+            get { return !m_IgnoreCanvasScaler; }
+            set
+            {
+                if (m_IgnoreCanvasScaler != value) return;
+                m_IgnoreCanvasScaler = !value;
+                UpdateTracker();
+            }
+        }
+
         internal bool useMeshSharing
         {
             get { return m_MeshSharing != MeshSharing.None; }
@@ -197,6 +216,8 @@ namespace Coffee.UIExtensions
         /// </summary>
         public bool isPaused { get; internal set; }
 
+        public Vector3 parentScale { get; private set; }
+
         public void Play()
         {
             particles.Exec(p => p.Simulate(0, false, true));
@@ -335,12 +356,10 @@ namespace Coffee.UIExtensions
 
         internal void UpdateTransformScale()
         {
-            //var newScale = Vector3.one;
+            parentScale = transform.parent.lossyScale;
-            //if (uiScaling)
+            if (!autoScaling) return;
-            //{
+
-            //    newScale = transform.parent.lossyScale.Inverse();
+            var newScale = parentScale.Inverse();
-            //}
-            var newScale = transform.parent.lossyScale.Inverse();
             if (transform.localScale != newScale)
             {
                 transform.localScale = newScale;
@@ -383,7 +402,7 @@ namespace Coffee.UIExtensions
             maskable = m_Maskable;
 #endif
             ResetGroupId();
-            _tracker.Add(this, rectTransform, DrivenTransformProperties.Scale);
+            UpdateTracker();
             UIParticleUpdater.Register(this);
             RegisterDirtyMaterialCallback(UpdateRendererMaterial);
 
@@ -416,7 +435,7 @@ namespace Coffee.UIExtensions
         /// </summary>
         protected override void OnDisable()
         {
-            _tracker.Clear();
+            UpdateTracker();
             UIParticleUpdater.Unregister(this);
             m_Renderers.ForEach(r => r.Reset());
             UnregisterDirtyMaterialCallback(UpdateRendererMaterial);
@@ -499,5 +518,25 @@ namespace Coffee.UIExtensions
 
             return _orthoCamera;
         }
+
+        private void UpdateTracker()
+        {
+            if (!enabled || !autoScaling)
+            {
+                _tracker.Clear();
+            }
+            else
+            {
+                _tracker.Add(this, rectTransform, DrivenTransformProperties.Scale);
+            }
+        }
+
+#if UNITY_EDITOR
+        protected override void OnValidate()
+        {
+            base.OnValidate();
+            UpdateTracker();
+        }
+#endif
     }
 }

Scripts/UIParticleRenderer.cs

@@ -430,16 +430,7 @@ namespace Coffee.UIExtensions
         private Vector3 GetWorldScale()
         {
             Profiler.BeginSample("[UIParticleRenderer] GetWorldScale");
-            var scale = _parent.scale3D;
+            var scale = _parent.scale3D.GetScaled(_parent.parentScale);
-            //if (_parent.uiScaling)
-            {
-                scale.Scale(_parent.transform.localScale.Inverse());
-            }
-            //else if (_parent.scalingMode == UIParticle.ScalingMode.UI && _particleSystem.main.scalingMode != ParticleSystemScalingMode.Hierarchy)
-            //{
-            //    var gscale = _parent.transform.lossyScale.GetScaled(canvas.transform.lossyScale.Inverse());
-            //    scale.Scale(gscale * canvas.scaleFactor);
-            //}
             Profiler.EndSample();
             return scale;
         }