CustomDepth stencil 2 on spline meshes, SplineNetwork rebuild, PP occluded (disabled)

- Enable RenderCustomDepth + stencil value 2 on spline tube mesh
- Restore stencil 2 on deselect (selection sets stencil 1 for outline)
- Auto-generated M_PS_Editor_SplineOccluded PP material (stencil + depth compare)
- PP occluded effect disabled for now (depth comparison unreliable)
- AISpline triggers SplineNetwork::RebuildNetwork on BeginPlay (next tick)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Unreal/Plugins/PS_BehaviorEditor/Source/PS_BehaviorEditor/PS_BehaviorEditor_AISpline.cpp

@@ -28,6 +28,8 @@ APS_BehaviorEditor_AISpline::APS_BehaviorEditor_AISpline()
 	SplineMeshComp->SetCollisionResponseToChannel(ECC_Camera, ECR_Block);
 	SplineMeshComp->bUseComplexAsSimpleCollision = true;
 	SplineMeshComp->SetCastShadow(false);
+	SplineMeshComp->SetRenderCustomDepth(true);
+	SplineMeshComp->SetCustomDepthStencilValue(2);
 
 	// Handle parent
 	HandleRoot = CreateDefaultSubobject<USceneComponent>(TEXT("HandleRoot"));
@@ -386,6 +388,7 @@ void APS_BehaviorEditor_AISpline::SetSelected(bool bSelected)
 	{
 		UMaterialInstanceDynamic* Mat = bSelected ? SplineMatSelected : SplineMat;
 		if (Mat) SplineMeshComp->SetMaterial(0, Mat);
+		SplineMeshComp->SetCustomDepthStencilValue(bSelected ? 1 : 2);
 	}
 	if (CenterCubeMat)
 	{

Unreal/Plugins/PS_Editor/Source/PS_Editor/GameMode/PS_Editor_Pawn.cpp

@@ -53,6 +53,9 @@ void APS_Editor_Pawn::BeginPlay()
 		OutlinePostProcess->Settings.WeightedBlendables.Array.Add(FWeightedBlendable(1.0f, OutlineMat));
 		UE_LOG(LogTemp, Log, TEXT("PS_Editor: Selection outline material loaded"));
 	}
+
+	// TODO: Spline occluded PP material — disabled for now, depth comparison unreliable
+	// Consider translucent second-pass approach instead of post-process
 	else
 	{
 		UE_LOG(LogTemp, Warning, TEXT("PS_Editor: Outline material /PS_Editor/M_PS_Editor_SelectionOutline not found. "

Unreal/Plugins/PS_Editor/Source/PS_Editor/PS_Editor.cpp

@@ -16,6 +16,7 @@
 #include "Materials/MaterialExpressionComponentMask.h"
 #include "Materials/MaterialExpressionAppendVector.h"
 #include "Materials/MaterialExpressionVectorParameter.h"
+#include "Materials/MaterialExpressionIf.h"
 #include "AssetRegistry/AssetRegistryModule.h"
 #include "UObject/SavePackage.h"
 #include "Misc/PackageName.h"
@@ -220,6 +221,168 @@ static void CreateOutlineMaterialAsset()
 	UE_LOG(LogTemp, Log, TEXT("PS_Editor: Selection outline material auto-generated (8-sample, dynamic resolution)"));
 }
 
+static void CreateSplineOccludedMaterialAsset()
+{
+	const FString MaterialPath = TEXT("/PS_Editor/M_PS_Editor_SplineOccluded");
+	const FString AssetName = TEXT("M_PS_Editor_SplineOccluded");
+
+	if (LoadObject<UMaterial>(nullptr, *(MaterialPath + TEXT(".") + AssetName)))
+	{
+		return;
+	}
+
+	UPackage* Package = CreatePackage(*MaterialPath);
+	UMaterial* Mat = NewObject<UMaterial>(Package, *AssetName, RF_Public | RF_Standalone);
+	Mat->MaterialDomain = EMaterialDomain::MD_PostProcess;
+	Mat->BlendableLocation = BL_SceneColorAfterDOF;
+
+	auto AddExpr = [&](UMaterialExpression* Expr) { Mat->GetExpressionCollection().AddExpression(Expr); };
+
+	// ---- Scene inputs ----
+	UMaterialExpressionSceneTexture* SceneColor = NewObject<UMaterialExpressionSceneTexture>(Mat);
+	SceneColor->SceneTextureId = PPI_PostProcessInput0;
+	AddExpr(SceneColor);
+	SceneColor->MaterialExpressionEditorX = -400;
+	SceneColor->MaterialExpressionEditorY = 0;
+
+	UMaterialExpressionSceneTexture* CustomStencil = NewObject<UMaterialExpressionSceneTexture>(Mat);
+	CustomStencil->SceneTextureId = PPI_CustomStencil;
+	AddExpr(CustomStencil);
+	CustomStencil->MaterialExpressionEditorX = -400;
+	CustomStencil->MaterialExpressionEditorY = 200;
+
+	UMaterialExpressionSceneTexture* CustomDepthTex = NewObject<UMaterialExpressionSceneTexture>(Mat);
+	CustomDepthTex->SceneTextureId = PPI_CustomDepth;
+	AddExpr(CustomDepthTex);
+	CustomDepthTex->MaterialExpressionEditorX = -400;
+	CustomDepthTex->MaterialExpressionEditorY = 400;
+
+	UMaterialExpressionSceneTexture* SceneDepthTex = NewObject<UMaterialExpressionSceneTexture>(Mat);
+	SceneDepthTex->SceneTextureId = PPI_SceneDepth;
+	AddExpr(SceneDepthTex);
+	SceneDepthTex->MaterialExpressionEditorX = -400;
+	SceneDepthTex->MaterialExpressionEditorY = 600;
+
+	// ---- Stencil == 2 check: abs(stencil - 2) < 0.5 ----
+	UMaterialExpressionConstant* StencilTarget = NewObject<UMaterialExpressionConstant>(Mat);
+	StencilTarget->R = 2.0f;
+	AddExpr(StencilTarget);
+	StencilTarget->MaterialExpressionEditorX = -200;
+	StencilTarget->MaterialExpressionEditorY = 200;
+
+	UMaterialExpressionSubtract* StencilDiff = NewObject<UMaterialExpressionSubtract>(Mat);
+	AddExpr(StencilDiff);
+	StencilDiff->A.Connect(0, CustomStencil);
+	StencilDiff->B.Connect(0, StencilTarget);
+	StencilDiff->MaterialExpressionEditorX = 0;
+	StencilDiff->MaterialExpressionEditorY = 200;
+
+	UMaterialExpressionAbs* StencilAbs = NewObject<UMaterialExpressionAbs>(Mat);
+	AddExpr(StencilAbs);
+	StencilAbs->Input.Connect(0, StencilDiff);
+	StencilAbs->MaterialExpressionEditorX = 200;
+	StencilAbs->MaterialExpressionEditorY = 200;
+
+	// Constants for IF outputs
+	UMaterialExpressionConstant* One = NewObject<UMaterialExpressionConstant>(Mat);
+	One->R = 1.0f;
+	AddExpr(One);
+	One->MaterialExpressionEditorX = 200;
+	One->MaterialExpressionEditorY = 100;
+
+	UMaterialExpressionConstant* Zero = NewObject<UMaterialExpressionConstant>(Mat);
+	Zero->R = 0.0f;
+	AddExpr(Zero);
+	Zero->MaterialExpressionEditorX = 200;
+	Zero->MaterialExpressionEditorY = 350;
+
+	UMaterialExpressionConstant* Half = NewObject<UMaterialExpressionConstant>(Mat);
+	Half->R = 0.5f;
+	AddExpr(Half);
+	Half->MaterialExpressionEditorX = 200;
+	Half->MaterialExpressionEditorY = 250;
+
+	// IF(Half > StencilAbs, 1, 0) → IsSpline
+	UMaterialExpressionIf* IsSpline = NewObject<UMaterialExpressionIf>(Mat);
+	AddExpr(IsSpline);
+	IsSpline->A.Connect(0, Half);
+	IsSpline->B.Connect(0, StencilAbs);
+	IsSpline->AGreaterThanB.Connect(0, One);
+	IsSpline->AEqualsB.Connect(0, Zero);
+	IsSpline->ALessThanB.Connect(0, Zero);
+	IsSpline->MaterialExpressionEditorX = 400;
+	IsSpline->MaterialExpressionEditorY = 200;
+
+	// ---- Depth comparison: CustomDepth > SceneDepth + 1 ----
+	UMaterialExpressionConstant* DepthBias = NewObject<UMaterialExpressionConstant>(Mat);
+	DepthBias->R = 1.0f;
+	AddExpr(DepthBias);
+	DepthBias->MaterialExpressionEditorX = -200;
+	DepthBias->MaterialExpressionEditorY = 600;
+
+	UMaterialExpressionAdd* SceneDepthBiased = NewObject<UMaterialExpressionAdd>(Mat);
+	AddExpr(SceneDepthBiased);
+	SceneDepthBiased->A.Connect(0, SceneDepthTex);
+	SceneDepthBiased->B.Connect(0, DepthBias);
+	SceneDepthBiased->MaterialExpressionEditorX = 0;
+	SceneDepthBiased->MaterialExpressionEditorY = 600;
+
+	// IF(CustomDepth > SceneDepth+1, 1, 0) → IsOccluded
+	UMaterialExpressionIf* IsOccluded = NewObject<UMaterialExpressionIf>(Mat);
+	AddExpr(IsOccluded);
+	IsOccluded->A.Connect(0, CustomDepthTex);
+	IsOccluded->B.Connect(0, SceneDepthBiased);
+	IsOccluded->AGreaterThanB.Connect(0, One);
+	IsOccluded->AEqualsB.Connect(0, Zero);
+	IsOccluded->ALessThanB.Connect(0, Zero);
+	IsOccluded->MaterialExpressionEditorX = 400;
+	IsOccluded->MaterialExpressionEditorY = 500;
+
+	// ---- Final mask = IsSpline * IsOccluded * 0.6 ----
+	UMaterialExpressionMultiply* CombinedMask = NewObject<UMaterialExpressionMultiply>(Mat);
+	AddExpr(CombinedMask);
+	CombinedMask->A.Connect(0, IsSpline);
+	CombinedMask->B.Connect(0, IsOccluded);
+	CombinedMask->MaterialExpressionEditorX = 600;
+	CombinedMask->MaterialExpressionEditorY = 350;
+
+	UMaterialExpressionMultiply* FinalMask = NewObject<UMaterialExpressionMultiply>(Mat);
+	AddExpr(FinalMask);
+	FinalMask->A.Connect(0, CombinedMask);
+	FinalMask->ConstB = 0.6f;
+	FinalMask->MaterialExpressionEditorX = 800;
+	FinalMask->MaterialExpressionEditorY = 350;
+
+	// ---- Gray color ----
+	UMaterialExpressionConstant4Vector* GrayColor = NewObject<UMaterialExpressionConstant4Vector>(Mat);
+	GrayColor->Constant = FLinearColor(0.35f, 0.35f, 0.35f, 1.0f);
+	AddExpr(GrayColor);
+	GrayColor->MaterialExpressionEditorX = 600;
+	GrayColor->MaterialExpressionEditorY = 600;
+
+	// ---- Lerp(SceneColor, GrayColor, FinalMask) ----
+	UMaterialExpressionLinearInterpolate* Lerp = NewObject<UMaterialExpressionLinearInterpolate>(Mat);
+	AddExpr(Lerp);
+	Lerp->A.Connect(0, SceneColor);
+	Lerp->B.Connect(0, GrayColor);
+	Lerp->Alpha.Connect(0, FinalMask);
+	Lerp->MaterialExpressionEditorX = 1000;
+	Lerp->MaterialExpressionEditorY = 200;
+
+	Mat->GetEditorOnlyData()->EmissiveColor.Connect(0, Lerp);
+
+	Mat->PreEditChange(nullptr);
+	Mat->PostEditChange();
+
+	FString PackageFilename = FPackageName::LongPackageNameToFilename(MaterialPath, FPackageName::GetAssetPackageExtension());
+	FSavePackageArgs SaveArgs;
+	SaveArgs.TopLevelFlags = RF_Public | RF_Standalone;
+	UPackage::SavePackage(Package, Mat, *PackageFilename, SaveArgs);
+	FAssetRegistryModule::AssetCreated(Mat);
+
+	UE_LOG(LogTemp, Log, TEXT("PS_Editor: Spline occluded PP material auto-generated (stencil 2, depth compare)"));
+}
+
 static void CreateSplineLineMaterialAsset()
 {
 	const FString MaterialPath = TEXT("/PS_Editor/M_PS_Editor_SplineLine");
@@ -270,6 +433,7 @@ void FPS_EditorModule::StartupModule()
 #if WITH_EDITOR
 	FCoreDelegates::OnPostEngineInit.AddStatic(&CreateOutlineMaterialAsset);
 	FCoreDelegates::OnPostEngineInit.AddStatic(&CreateSplineLineMaterialAsset);
+	FCoreDelegates::OnPostEngineInit.AddStatic(&CreateSplineOccludedMaterialAsset);
 #endif
 }
 

Unreal/Plugins/PS_Editor/Source/PS_Editor/Spline/PS_Editor_SplineActor.cpp

@@ -30,6 +30,8 @@ APS_Editor_SplineActor::APS_Editor_SplineActor()
 	SplineMeshComp->SetCollisionResponseToChannel(ECC_Camera, ECR_Block);
 	SplineMeshComp->bUseComplexAsSimpleCollision = true;
 	SplineMeshComp->SetCastShadow(false);
+	SplineMeshComp->SetRenderCustomDepth(true);
+	SplineMeshComp->SetCustomDepthStencilValue(2);
 
 	// Handle parent
 	HandleRoot = CreateDefaultSubobject<USceneComponent>(TEXT("HandleRoot"));
@@ -421,15 +423,12 @@ void APS_Editor_SplineActor::SetSelected(bool bSelected)
 	if (SplineMeshComp)
 	{
 		UMaterialInstanceDynamic* Mat = bSelected ? SplineMatSelected : SplineMat;
-		UE_LOG(LogTemp, Log, TEXT("PS_Editor: SetSelected(%s) - SplineMat=%s, SplineMatSelected=%s, Using=%s"),
-			bSelected ? TEXT("true") : TEXT("false"),
-			SplineMat ? TEXT("valid") : TEXT("NULL"),
-			SplineMatSelected ? TEXT("valid") : TEXT("NULL"),
-			Mat ? TEXT("valid") : TEXT("NULL"));
 		if (Mat)
 		{
 			SplineMeshComp->SetMaterial(0, Mat);
 		}
+		// Restore stencil 2 for occluded PP effect when deselected (selection sets it to 1)
+		SplineMeshComp->SetCustomDepthStencilValue(bSelected ? 1 : 2);
 	}
 
 	// Center cube: selected color when selected, normal color otherwise