From 1c33dac1255dca4ee00214fcfd6e10cf79256c73 Mon Sep 17 00:00:00 2001
From: mob-sakai <12690315+mob-sakai@users.noreply.github.com>
Date: Wed, 1 Jan 2025 10:05:46 +0900
Subject: [PATCH] fix: sub-emitter's `inherit velocity` module doubles at
 runtime

close #349
---
 Runtime/UIParticle.cs                         |  6 +++--
 Runtime/UIParticleRenderer.cs                 | 10 ++++----
 Runtime/Utilities/ParticleSystemExtensions.cs | 25 +++++++++++++++++++
 3 files changed, 34 insertions(+), 7 deletions(-)

diff --git a/Runtime/UIParticle.cs b/Runtime/UIParticle.cs
index 5ad390d..f0a2bed 100644
--- a/Runtime/UIParticle.cs
+++ b/Runtime/UIParticle.cs
@@ -577,12 +577,14 @@ namespace Coffee.UIExtensions
             {
                 var ps = particleSystems[i];
                 if (!ps) continue;
-                GetRenderer(j++).Set(this, ps, false);
+
+                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);
                 }
             }
         }
diff --git a/Runtime/UIParticleRenderer.cs b/Runtime/UIParticleRenderer.cs
index 80936b8..e85d258 100644
--- a/Runtime/UIParticleRenderer.cs
+++ b/Runtime/UIParticleRenderer.cs
@@ -40,6 +40,7 @@ namespace Coffee.UIExtensions
         private Vector2Int _prevScreenSize;
         private bool _preWarm;
         private ParticleSystemRenderer _renderer;
+        private ParticleSystem _mainEmitter;
 
         public override Texture mainTexture => _isTrail ? null : _particleSystem.GetTextureForSprite();
 
@@ -112,6 +113,7 @@ namespace Coffee.UIExtensions
             _parent = null;
             _particleSystem = null;
             _renderer = null;
+            _mainEmitter = null;
             if (0 <= index)
             {
                 _index = index;
@@ -223,7 +225,7 @@ 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 +248,7 @@ 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 +265,7 @@ namespace Coffee.UIExtensions
             _prevScreenSize = new Vector2Int(Screen.width, Screen.height);
             _prevCanvasScale = canvas ? canvas.scaleFactor : 1f;
             _delay = true;
+            _mainEmitter = mainEmitter;
 
             canvasRenderer.SetTexture(null);
 
@@ -303,7 +303,7 @@ namespace Coffee.UIExtensions
 
             // Simulate particles.
             Profiler.BeginSample("[UIParticle] Bake Mesh > Simulate Particles");
-            if (!_isTrail && _parent.canSimulate)
+            if (!_isTrail && _parent.canSimulate && !_mainEmitter)
             {
 #if UNITY_EDITOR
                 if (!Application.isPlaying)
diff --git a/Runtime/Utilities/ParticleSystemExtensions.cs b/Runtime/Utilities/ParticleSystemExtensions.cs
index 48329f0..b9c08a0 100644
--- a/Runtime/Utilities/ParticleSystemExtensions.cs
+++ b/Runtime/Utilities/ParticleSystemExtensions.cs
@@ -171,5 +171,30 @@ namespace Coffee.UIParticleInternal
                 action.Invoke(p);
             }
         }
+
+        public static ParticleSystem GetMainEmitter(this ParticleSystem self, List<ParticleSystem> list)
+        {
+            if (!self || 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)
+        {
+            var subEmitters = parent.subEmitters;
+            var count = subEmitters.subEmittersCount;
+            for (var i = 0; i < count; i++)
+            {
+                if (subEmitters.GetSubEmitterSystem(i) == self) return true;
+            }
+
+            return false;
+        }
     }
 }