From dbd829761265dd718b951324b67bb7efead2ea0e Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Tue, 24 Jun 2025 19:25:18 +0200
Subject: [PATCH] Add `SortOrder` to Environment Probe

---
 Source/Engine/Level/Actors/EnvironmentProbe.cpp |  3 +++
 Source/Engine/Level/Actors/EnvironmentProbe.h   |  6 ++++++
 Source/Engine/Renderer/ReflectionsPass.cpp      | 13 +++++++++----
 Source/Engine/Renderer/RenderList.h             |  1 +
 4 files changed, 19 insertions(+), 4 deletions(-)

diff --git a/Source/Engine/Level/Actors/EnvironmentProbe.cpp b/Source/Engine/Level/Actors/EnvironmentProbe.cpp
index 3c49611d4..71b403eb9 100644
--- a/Source/Engine/Level/Actors/EnvironmentProbe.cpp
+++ b/Source/Engine/Level/Actors/EnvironmentProbe.cpp
@@ -197,6 +197,7 @@ void EnvironmentProbe::Draw(RenderContext& renderContext)
             data.Position = position;
             data.Radius = radius;
             data.Brightness = Brightness;
+            data.SortOrder = SortOrder;
             data.HashID = GetHash(_id);
             renderContext.List->EnvironmentProbes.Add(data);
         }
@@ -234,6 +235,7 @@ void EnvironmentProbe::Serialize(SerializeStream& stream, const void* otherObj)
     SERIALIZE_MEMBER(Radius, _radius);
     SERIALIZE(CubemapResolution);
     SERIALIZE(Brightness);
+    SERIALIZE(SortOrder);
     SERIALIZE(UpdateMode);
     SERIALIZE(CaptureNearPlane);
     SERIALIZE_MEMBER(IsCustomProbe, _isUsingCustomProbe);
@@ -248,6 +250,7 @@ void EnvironmentProbe::Deserialize(DeserializeStream& stream, ISerializeModifier
     DESERIALIZE_MEMBER(Radius, _radius);
     DESERIALIZE(CubemapResolution);
     DESERIALIZE(Brightness);
+    DESERIALIZE(SortOrder);
     DESERIALIZE(UpdateMode);
     DESERIALIZE(CaptureNearPlane);
     DESERIALIZE_MEMBER(IsCustomProbe, _isUsingCustomProbe);
diff --git a/Source/Engine/Level/Actors/EnvironmentProbe.h b/Source/Engine/Level/Actors/EnvironmentProbe.h
index 7131dc0ba..09f771437 100644
--- a/Source/Engine/Level/Actors/EnvironmentProbe.h
+++ b/Source/Engine/Level/Actors/EnvironmentProbe.h
@@ -51,6 +51,12 @@ public:
     API_FIELD(Attributes="EditorOrder(10), Limit(0, 1000, 0.01f), EditorDisplay(\"Probe\")")
     float Brightness = 1.0f;
 
+    /// <summary>
+    /// The probe rendering order. The higher values are render later (on top).
+    /// </summary>
+    API_FIELD(Attributes = "EditorOrder(25), EditorDisplay(\"Probe\")")
+    int32 SortOrder = 0;
+
     /// <summary>
     /// The probe update mode.
     /// </summary>
diff --git a/Source/Engine/Renderer/ReflectionsPass.cpp b/Source/Engine/Renderer/ReflectionsPass.cpp
index 3aa0ed6ee..631543010 100644
--- a/Source/Engine/Renderer/ReflectionsPass.cpp
+++ b/Source/Engine/Renderer/ReflectionsPass.cpp
@@ -335,12 +335,17 @@ void ReflectionsPass::Dispose()
 
 bool SortProbes(RenderEnvironmentProbeData const& p1, RenderEnvironmentProbeData const& p2)
 {
-    // Compare by radius
-    int32 res = static_cast<int32>(p2.Radius - p1.Radius);
+    // Compare by Sort Order
+    int32 res = p1.SortOrder - p2.SortOrder;
     if (res == 0)
     {
-        // Compare by ID to prevent flickering
-        res = p2.HashID - p1.HashID;
+        // Compare by radius
+        res = static_cast<int32>(p2.Radius - p1.Radius);
+        if (res == 0)
+        {
+            // Compare by ID to prevent flickering
+            res = p2.HashID - p1.HashID;
+        }
     }
     return res < 0;
 }
diff --git a/Source/Engine/Renderer/RenderList.h b/Source/Engine/Renderer/RenderList.h
index 469bc2cdd..d5288e6ee 100644
--- a/Source/Engine/Renderer/RenderList.h
+++ b/Source/Engine/Renderer/RenderList.h
@@ -155,6 +155,7 @@ struct RenderEnvironmentProbeData
     Float3 Position;
     float Radius;
     float Brightness;
+    int32 SortOrder;
     uint32 HashID;
 
     void SetShaderData(ShaderEnvProbeData& data) const;