From 3ba1ebb847c056dc94230f1900b2c118ee0b88a7 Mon Sep 17 00:00:00 2001
From: Chandler Cox <mr.chandlercox@gmail.com>
Date: Thu, 12 Dec 2024 20:41:11 -0600
Subject: [PATCH] Add rotate position shape as particle module.

---
 .../Surface/Archetypes/ParticleModules.cs     | 19 ++++++++++
 ...rticleEmitterGraph.CPU.ParticleModules.cpp | 37 +++++++++++++++++++
 ...rticleEmitterGraph.GPU.ParticleModules.cpp | 14 +++++++
 3 files changed, 70 insertions(+)

diff --git a/Source/Editor/Surface/Archetypes/ParticleModules.cs b/Source/Editor/Surface/Archetypes/ParticleModules.cs
index 9dbfbce77..6ee1270ac 100644
--- a/Source/Editor/Surface/Archetypes/ParticleModules.cs
+++ b/Source/Editor/Surface/Archetypes/ParticleModules.cs
@@ -924,6 +924,25 @@ namespace FlaxEditor.Surface.Archetypes
                     (int)ModuleType.Initialize,
                 },
             },
+            new NodeArchetype
+            {
+                TypeID = 216,
+                Create = CreateParticleModuleNode,
+                Title = "Rotate Position Shape",
+                Description = "Rotate the shape.",
+                Flags = DefaultModuleFlags,
+                Size = new Float2(200, 1 * Surface.Constants.LayoutOffsetY),
+                DefaultValues = new object[]
+                {
+                    true,
+                    (int)ModuleType.Initialize,
+                    Quaternion.Identity,
+                },
+                Elements = new []
+                {
+                    NodeElementArchetype.Factory.Input(-0.5f, "Rotation", true, typeof(Quaternion), 0, 2),
+                }
+            },
             GetParticleAttribute(ModuleType.Initialize, 250, "Set Position", "Sets the particle position", typeof(Float3), Float3.Zero),
             GetParticleAttribute(ModuleType.Initialize, 251, "Set Lifetime", "Sets the particle lifetime (in seconds)", typeof(float), 10.0f),
             GetParticleAttribute(ModuleType.Initialize, 252, "Set Age", "Sets the particle age (in seconds)", typeof(float), 0.0f),
diff --git a/Source/Engine/Particles/Graph/CPU/ParticleEmitterGraph.CPU.ParticleModules.cpp b/Source/Engine/Particles/Graph/CPU/ParticleEmitterGraph.CPU.ParticleModules.cpp
index 28013b5b9..98642b34f 100644
--- a/Source/Engine/Particles/Graph/CPU/ParticleEmitterGraph.CPU.ParticleModules.cpp
+++ b/Source/Engine/Particles/Graph/CPU/ParticleEmitterGraph.CPU.ParticleModules.cpp
@@ -1150,6 +1150,43 @@ void ParticleEmitterGraphCPUExecutor::ProcessModule(ParticleEmitterGraphCPUNode*
         // Not supported
         break;
     }
+    // Rotate Position Shape
+    case 216:
+    {
+        PARTICLE_EMITTER_MODULE("Rotate Position Shape");
+        auto& positionAttr = context.Data->Buffer->Layout->Attributes[node->Attributes[0]];
+
+        byte* positionPtr = start + positionAttr.Offset;
+
+        auto quatBox = node->GetBox(0);
+
+#define INPUTS_FETCH() \
+const Quaternion quat = (Quaternion)GetValue(quatBox, 2);
+#define LOGIC() \
+*(Float3*)positionPtr = quat * *((Float3*)positionPtr); \
+positionPtr += stride;
+
+        if (node->UsePerParticleDataResolve())
+        {
+            for (int32 particleIndex = particlesStart; particleIndex < particlesEnd; particleIndex++)
+            {
+                context.ParticleIndex = particleIndex;
+                INPUTS_FETCH();
+                LOGIC();
+            }
+        }
+        else
+        {
+            INPUTS_FETCH();
+            for (int32 particleIndex = particlesStart; particleIndex < particlesEnd; particleIndex++)
+            {
+                LOGIC();
+            }
+        }
+#undef INPUTS_FETCH
+#undef LOGIC
+        break;
+    }
 
     // Helper macros for collision modules to share the code
 #define COLLISION_BEGIN() \
diff --git a/Source/Engine/Particles/Graph/GPU/ParticleEmitterGraph.GPU.ParticleModules.cpp b/Source/Engine/Particles/Graph/GPU/ParticleEmitterGraph.GPU.ParticleModules.cpp
index bbf4ccdf7..160097b75 100644
--- a/Source/Engine/Particles/Graph/GPU/ParticleEmitterGraph.GPU.ParticleModules.cpp
+++ b/Source/Engine/Particles/Graph/GPU/ParticleEmitterGraph.GPU.ParticleModules.cpp
@@ -632,6 +632,20 @@ void ParticleEmitterGPUGenerator::ProcessModule(Node* node)
             ), position.Value, param.ShaderName, wsPos);
         break;
     }
+    // Rotate position shape
+    case 216:
+    {
+        auto positionAttr = AccessParticleAttribute(node, nodeGpu->Attributes[0], AccessMode::Write);
+        const Value quaternion = tryGetValue(node->GetBox(0), Value::InitForZero(VariantType::Quaternion)).Cast(VariantType::Quaternion);
+        _writer.Write(
+            TEXT(
+                "   {{\n"
+                "       // Rotate position shape\n"
+                "       {0} = QuatRotateVector({1}, {0});\n"
+                "   }}\n"
+                ), positionAttr.Value, quaternion.Value);
+        break;
+    }
 
     // Helper macros for collision modules to share the code
 #define COLLISION_BEGIN() \