MI stuff is now workign

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialInstance_ClearParameter.h

@@ -0,0 +1,80 @@
+#pragma once
+
+#include "CoreMinimal.h"
+#include "MCPHandler.h"
+#include "MCPFetcher.h"
+#include "MCPUtils.h"
+#include "Materials/MaterialInstanceConstant.h"
+#include "MaterialTypes.h"
+#include "MaterialInstance_ClearParameter.generated.h"
+
+
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+
+UCLASS()
+class UMCP_MaterialInstance_ClearParameter : public UObject, public IMCPHandler
+{
+	GENERATED_BODY()
+
+public:
+	UPROPERTY(meta=(Description="Material Instance path"))
+	FString Path;
+
+	UPROPERTY(meta=(Description="Parameter name to clear"))
+	FString Parameter;
+
+	UPROPERTY(meta=(Description="Parameter association: 'Global', 'Layer', or 'Blend'. Default: 'Global'", Optional))
+	FString ParameterAssociation = TEXT("Global");
+
+	UPROPERTY(meta=(Description="Layer/blend index (0-based). Only used when ParameterAssociation is 'Layer' or 'Blend'", Optional))
+	int32 ParameterLayer = INDEX_NONE;
+
+	virtual FString GetDescription() const override
+	{
+		return TEXT("Remove a parameter override from a Material Instance, reverting it to the parent material's value.");
+	}
+
+	virtual void Handle(const FJsonObject* Json, FStringBuilderBase& Result) override
+	{
+		MCPFetcher F(Result);
+		UMaterialInstanceConstant* MI = F.Asset(Path).Cast<UMaterialInstanceConstant>();
+		if (!MI) return;
+
+		// Parse the association string.
+		EMaterialParameterAssociation Association;
+		if (!MCPUtils::ParseMaterialParameterAssociation(ParameterAssociation, Association, Result))
+			return;
+
+		FMaterialParameterInfo ParamID(*Parameter, Association, ParameterLayer);
+
+		// Remove the override from all parameter arrays.
+		auto RemoveFrom = [&](auto& Arr) {
+			return Arr.RemoveAll([&](auto& Entry) { return Entry.ParameterInfo == ParamID; });
+		};
+
+		F.PreEdit();
+		int32 Removed = 0;
+		Removed += RemoveFrom(MI->ScalarParameterValues);
+		Removed += RemoveFrom(MI->VectorParameterValues);
+		Removed += RemoveFrom(MI->DoubleVectorParameterValues);
+		Removed += RemoveFrom(MI->TextureParameterValues);
+		Removed += RemoveFrom(MI->TextureCollectionParameterValues);
+		Removed += RemoveFrom(MI->RuntimeVirtualTextureParameterValues);
+		Removed += RemoveFrom(MI->SparseVolumeTextureParameterValues);
+		Removed += RemoveFrom(MI->FontParameterValues);
+		F.PostEdit();
+
+		if (Removed == 0)
+		{
+			Result.Appendf(TEXT("No override found for parameter '%s' (association=%s layer=%d) on %s"),
+				*Parameter, *ParameterAssociation, ParameterLayer, *MCPUtils::FormatName(MI));
+			return;
+		}
+
+		MCPUtils::SaveGenericPackage(MI);
+		Result.Appendf(TEXT("Cleared override for '%s' on %s\n"),
+			*Parameter, *MCPUtils::FormatName(MI));
+	}
+};

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialInstance_DumpParameters.h

@@ -2,16 +2,10 @@
 
 #include "CoreMinimal.h"
 #include "MCPHandler.h"
-#include "MCPAssetFinder.h"
+#include "MCPFetcher.h"
 #include "MCPUtils.h"
-#include "Materials/Material.h"
-#include "Materials/MaterialInterface.h"
 #include "Materials/MaterialInstanceConstant.h"
-#include "Materials/MaterialExpressionScalarParameter.h"
+#include "MaterialTypes.h"
-#include "Materials/MaterialExpressionVectorParameter.h"
-#include "Materials/MaterialExpressionTextureSampleParameter2D.h"
-#include "Materials/MaterialExpressionStaticSwitchParameter.h"
-#include "Engine/Texture.h"
 #include "MaterialInstance_DumpParameters.generated.h"
 
 
@@ -25,144 +19,38 @@ class UMCP_MaterialInstance_DumpParameters : public UObject, public IMCPHandler
 	GENERATED_BODY()
 
 public:
-	UPROPERTY(meta=(Description="Material Instance name or path to inspect"))
+	UPROPERTY(meta=(Description="Material Instance path"))
-	FString MaterialInstance;
+	FString Path;
 
 	virtual FString GetDescription() const override
 	{
-		return TEXT("List all parameters on a Material Instance, including overridden and inherited parameters.");
+		return TEXT("List all parameters on a Material Instance, showing current values and which are overridden.");
 	}
 
 	virtual void Handle(const FJsonObject* Json, FStringBuilderBase& Result) override
 	{
-		MCPAssets<UMaterialInstanceConstant> Assets;
+		MCPFetcher F(Result);
-		if (!Assets.Exact(MaterialInstance).Errors(Result).ENone().ETwo().Load()) return;
+		UMaterialInstanceConstant* MI = F.Asset(Path).Cast<UMaterialInstanceConstant>();
-		UMaterialInstanceConstant* MI = Assets.Object();
+		if (!MI) return;
 
-		Result.Appendf(TEXT("MaterialInstance: %s\n"), *MCPUtils::FormatName(MI));
+		auto AllParams = MCPUtils::GetMaterialParameters(MI);
 
-		// Parent chain
+		// Overridden parameters first.
-		if (MI->Parent)
-		{
-			Result.Append(TEXT("Parent chain:"));
-			UMaterialInterface* Current = MI->Parent;
-			while (Current)
-			{
-				if (UMaterial* Mat = Cast<UMaterial>(Current))
-				{
-					Result.Appendf(TEXT(" %s"), *MCPUtils::FormatName(Mat));
-					break;
-				}
-				if (UMaterialInstance* ParentMI = Cast<UMaterialInstance>(Current))
-				{
-					Result.Appendf(TEXT(" %s ->"), *MCPUtils::FormatName(ParentMI));
-					UMaterialInstanceConstant* ParentMIC = Cast<UMaterialInstanceConstant>(Current);
-					Current = ParentMIC ? ParentMIC->Parent : nullptr;
-				}
-				else
-				{
-					Result.Appendf(TEXT(" %s"), *Current->GetPathName());
-					break;
-				}
-			}
-			Result.Append(TEXT("\n"));
-		}
-
-		// Collect names of overridden parameters for filtering inherited ones
-		TSet<FString> OverriddenScalars, OverriddenVectors, OverriddenTextures, OverriddenStaticSwitches;
-		for (const FScalarParameterValue& P : MI->ScalarParameterValues)
-			OverriddenScalars.Add(P.ParameterInfo.Name.ToString());
-		for (const FVectorParameterValue& P : MI->VectorParameterValues)
-			OverriddenVectors.Add(P.ParameterInfo.Name.ToString());
-		for (const FTextureParameterValue& P : MI->TextureParameterValues)
-			OverriddenTextures.Add(P.ParameterInfo.Name.ToString());
-		{
-			FStaticParameterSet SP;
-			MI->GetStaticParameterValues(SP);
-			for (const FStaticSwitchParameter& P : SP.StaticSwitchParameters)
-				if (P.bOverride)
-					OverriddenStaticSwitches.Add(P.ParameterInfo.Name.ToString());
-		}
-
-		// Overridden parameters
 		bool bHasOverrides = false;
-		auto EnsureOverrideHeader = [&]() {
+		for (auto& [Info, Meta] : AllParams)
+		{
+			if (!Meta.bOverride) continue;
 			if (!bHasOverrides) { Result.Append(TEXT("\nOverridden Parameters:\n")); bHasOverrides = true; }
-		};
+			MCPUtils::FormatMaterialParameter(Result, Info, Meta);
-
-		for (const FScalarParameterValue& P : MI->ScalarParameterValues)
-		{
-			EnsureOverrideHeader();
-			Result.Appendf(TEXT("  Scalar \"%s\" = %g\n"), *P.ParameterInfo.Name.ToString(), P.ParameterValue);
-		}
-		for (const FVectorParameterValue& P : MI->VectorParameterValues)
-		{
-			EnsureOverrideHeader();
-			Result.Appendf(TEXT("  Vector \"%s\" = (%.3f, %.3f, %.3f, %.3f)\n"),
-				*P.ParameterInfo.Name.ToString(),
-				P.ParameterValue.R, P.ParameterValue.G, P.ParameterValue.B, P.ParameterValue.A);
-		}
-		for (const FTextureParameterValue& P : MI->TextureParameterValues)
-		{
-			EnsureOverrideHeader();
-			Result.Appendf(TEXT("  Texture \"%s\" = %s\n"),
-				*P.ParameterInfo.Name.ToString(),
-				P.ParameterValue ? *MCPUtils::FormatName(P.ParameterValue) : TEXT("None"));
-		}
-		{
-			FStaticParameterSet StaticParams;
-			MI->GetStaticParameterValues(StaticParams);
-			for (const FStaticSwitchParameter& P : StaticParams.StaticSwitchParameters)
-			{
-				if (!P.bOverride) continue;
-				EnsureOverrideHeader();
-				Result.Appendf(TEXT("  StaticSwitch \"%s\" = %s\n"),
-					*P.ParameterInfo.Name.ToString(), P.Value ? TEXT("true") : TEXT("false"));
-			}
 		}
 
-		// Inherited (non-overridden) parameters from the base material
+		// Inherited (non-overridden) parameters.
-		UMaterial* BaseMat = MI->GetMaterial();
-		if (!BaseMat) return;
-
 		bool bHasInherited = false;
-		auto EnsureInheritedHeader = [&]() {
+		for (auto& [Info, Meta] : AllParams)
+		{
+			if (Meta.bOverride) continue;
 			if (!bHasInherited) { Result.Append(TEXT("\nInherited Parameters (not overridden):\n")); bHasInherited = true; }
-		};
+			MCPUtils::FormatMaterialParameter(Result, Info, Meta);
-
-		for (UMaterialExpression* Expr : BaseMat->GetExpressions())
-		{
-			if (!Expr) continue;
-
-			if (auto* SP = Cast<UMaterialExpressionScalarParameter>(Expr))
-			{
-				if (OverriddenScalars.Contains(SP->ParameterName.ToString())) continue;
-				EnsureInheritedHeader();
-				Result.Appendf(TEXT("  Scalar \"%s\" default=%g\n"), *SP->ParameterName.ToString(), SP->DefaultValue);
-			}
-			else if (auto* VP = Cast<UMaterialExpressionVectorParameter>(Expr))
-			{
-				if (OverriddenVectors.Contains(VP->ParameterName.ToString())) continue;
-				EnsureInheritedHeader();
-				Result.Appendf(TEXT("  Vector \"%s\" default=(%.3f, %.3f, %.3f, %.3f)\n"),
-					*VP->ParameterName.ToString(),
-					VP->DefaultValue.R, VP->DefaultValue.G, VP->DefaultValue.B, VP->DefaultValue.A);
-			}
-			else if (auto* TP = Cast<UMaterialExpressionTextureSampleParameter2D>(Expr))
-			{
-				if (OverriddenTextures.Contains(TP->ParameterName.ToString())) continue;
-				EnsureInheritedHeader();
-				Result.Appendf(TEXT("  Texture \"%s\" default=%s\n"),
-					*TP->ParameterName.ToString(),
-					TP->Texture ? *MCPUtils::FormatName(TP->Texture) : TEXT("None"));
-			}
-			else if (auto* SSP = Cast<UMaterialExpressionStaticSwitchParameter>(Expr))
-			{
-				if (OverriddenStaticSwitches.Contains(SSP->ParameterName.ToString())) continue;
-				EnsureInheritedHeader();
-				Result.Appendf(TEXT("  StaticSwitch \"%s\" default=%s\n"),
-					*SSP->ParameterName.ToString(), SSP->DefaultValue ? TEXT("true") : TEXT("false"));
-			}
 		}
 	}
 };

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/MaterialInstance_SetParameter.h

@@ -5,6 +5,7 @@
 #include "MCPFetcher.h"
 #include "MCPUtils.h"
 #include "Materials/MaterialInstanceConstant.h"
+#include "MaterialTypes.h"
 #include "Misc/DefaultValueHelper.h"
 #include "MaterialInstance_SetParameter.generated.h"
 
@@ -25,6 +26,12 @@ public:
 	UPROPERTY(meta=(Description="Parameter name to set"))
 	FString Parameter;
 
+	UPROPERTY(meta=(Description="Parameter association: 'Global', 'Layer', or 'Blend'. Default: 'Global'", Optional))
+	FString ParameterAssociation = TEXT("Global");
+
+	UPROPERTY(meta=(Description="Layer/blend index (0-based). Only used when ParameterAssociation is 'Layer' or 'Blend'", Optional))
+	int32 ParameterLayer = INDEX_NONE;
+
 	UPROPERTY(meta=(Description="Value to set (uses Unreal text format, e.g. '0.5' for scalar, '(R=1,G=0,B=0,A=1)' for vector)"))
 	FString Value;
 
@@ -39,38 +46,30 @@ public:
 		UMaterialInstanceConstant* MI = F.Asset(Path).Cast<UMaterialInstanceConstant>();
 		if (!MI) return;
 
-		auto Parameters = MCPUtils::MaterialParameters(MI);
+		// Parse the association string.
+		EMaterialParameterAssociation Association;
+		if (!MCPUtils::ParseMaterialParameterAssociation(ParameterAssociation, Association, Result))
+			return;
 
-		// Find a parameter with a matching name.
+		// Build the parameter ID to look up.
-		FName Name(*Parameter);
+		FMaterialParameterInfo ParamID(*Parameter, Association, ParameterLayer);
-		MCPMaterialParameter* Found = nullptr;
+
-		int MatchCount = 0;
+		// Find it in the material's parameter map.
-		for (auto& P : Parameters)
+		auto AllParams = MCPUtils::GetMaterialParameters(MI);
+		FMaterialParameterMetadata* Found = AllParams.Find(ParamID);
+		if (!Found)
 		{
-			if (P.Name == Name)
+			Result.Appendf(TEXT("No parameter named '%s' with association=%s layer=%d"),
-			{
+				*Parameter, *ParameterAssociation, ParameterLayer);
-				MatchCount++;
-				Found = &P;
-			}
-		}
-		if (MatchCount > 1)
-		{
-			Result.Appendf(TEXT("More than one parameter named '%s'"), *Parameter);
 			return;
 		}
-		if (MatchCount == 0)
+		if (Found->PrimitiveDataIndex != INDEX_NONE)
-		{
-			Result.Appendf(TEXT("No parameter named '%s'"), *Parameter);
-			return;
-		}
-		if (Found->Metadata.PrimitiveDataIndex != INDEX_NONE)
 		{
 			Result.Appendf(TEXT("Parameter '%s' uses custom primitive data and cannot be set on a material instance"), *Parameter);
 			return;
 		}
 
-		FMaterialParameterInfo Info(*Parameter);
+		EMaterialParameterType Type = Found->Value.Type;
-		EMaterialParameterType Type = Found->Metadata.Value.Type;
 
 		F.PreEdit();
 		switch (Type)
@@ -83,7 +82,7 @@ public:
 				Result.Appendf(TEXT("Failed to parse '%s' as a float"), *Value);
 				return;
 			}
-			MI->SetScalarParameterValueEditorOnly(Info, ScalarValue);
+			MI->SetScalarParameterValueEditorOnly(ParamID, ScalarValue);
 			break;
 		}
 		case EMaterialParameterType::Vector:
@@ -94,11 +93,11 @@ public:
 				Result.Appendf(TEXT("Failed to parse '%s' as a color/vector (expected format: '(R=1,G=0,B=0,A=1)')"), *Value);
 				return;
 			}
-			MI->SetVectorParameterValueEditorOnly(Info, Color);
+			MI->SetVectorParameterValueEditorOnly(ParamID, Color);
 			break;
 		}
 		default:
-			Result.Appendf(TEXT("Unsupported parameter type for '%s'"), *Parameter);
+			Result.Appendf(TEXT("Parameters of type %d (see EMaterialParameterType) are not implemented"), (int)Type);
 			return;
 		}
 		F.PostEdit();

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_DumpParameters.h

@@ -0,0 +1,43 @@
+#pragma once
+
+#include "CoreMinimal.h"
+#include "MCPHandler.h"
+#include "MCPFetcher.h"
+#include "MCPUtils.h"
+#include "Materials/Material.h"
+#include "MaterialTypes.h"
+#include "Material_DumpParameters.generated.h"
+
+
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+// ---------------------------------------------------------------------------
+
+UCLASS()
+class UMCP_Material_DumpParameters : public UObject, public IMCPHandler
+{
+	GENERATED_BODY()
+
+public:
+	UPROPERTY(meta=(Description="Material path"))
+	FString Path;
+
+	virtual FString GetDescription() const override
+	{
+		return TEXT("List all parameters on a Material, showing their default values.");
+	}
+
+	virtual void Handle(const FJsonObject* Json, FStringBuilderBase& Result) override
+	{
+		MCPFetcher F(Result);
+		UMaterial* Mat = F.Asset(Path).Cast<UMaterial>();
+		if (!Mat) return;
+
+		auto AllParams = MCPUtils::GetMaterialParameters(Mat);
+
+		for (auto& [Info, Meta] : AllParams)
+		{
+			MCPUtils::FormatMaterialParameter(Result, Info, Meta);
+		}
+	}
+};

Plugins/BlueprintMCP/Source/BlueprintMCP/Handlers/Material_SetInstanceParameter.h

@@ -1,206 +0,0 @@
-#pragma once
-
-#include "CoreMinimal.h"
-#include "MCPHandler.h"
-#include "MCPAssetFinder.h"
-#include "MCPUtils.h"
-#include "Materials/Material.h"
-#include "Materials/MaterialInterface.h"
-#include "Materials/MaterialInstanceConstant.h"
-#include "Materials/MaterialExpressionScalarParameter.h"
-#include "Materials/MaterialExpressionVectorParameter.h"
-#include "Materials/MaterialExpressionTextureSampleParameter2D.h"
-#include "Materials/MaterialExpressionStaticSwitchParameter.h"
-#include "Engine/Texture.h"
-#include "Material_SetInstanceParameter.generated.h"
-
-
-// ---------------------------------------------------------------------------
-// ---------------------------------------------------------------------------
-// ---------------------------------------------------------------------------
-
-UCLASS()
-class UMCP_Material_SetInstanceParameter : public UObject, public IMCPHandler
-{
-	GENERATED_BODY()
-
-public:
-	UPROPERTY(meta=(Description="Material Instance name or path"))
-	FString MaterialInstance;
-
-	UPROPERTY(meta=(Description="Parameter name to set"))
-	FString ParameterName;
-
-	UPROPERTY(meta=(Description="Value to set (number for scalar, object with r/g/b/a for vector, string path for texture, bool for staticSwitch)"))
-	FMCPJsonObject Value;
-
-	UPROPERTY(meta=(Optional, Description="Parameter type: scalar, vector, texture, staticSwitch. Auto-detected from parent if omitted."))
-	FString Type;
-
-	UPROPERTY(meta=(Optional, Description="If true, validate without applying changes"))
-	bool DryRun = false;
-
-	virtual FString GetDescription() const override
-	{
-		return TEXT("Set a parameter override on a Material Instance. "
-			"Supports scalar, vector, texture, and static switch parameter types.");
-	}
-
-	virtual void Handle(const FJsonObject* Json, FStringBuilderBase& Result) override
-	{
-		if (!Json->HasField(TEXT("value")))
-		{
-			Result.Append(TEXT("ERROR: Missing required field: value\n"));
-			return;
-		}
-
-		// Load the Material Instance
-		MCPAssets<UMaterialInstanceConstant> Assets;
-		if (!Assets.Exact(MaterialInstance).Errors(Result).ENone().ETwo().Load()) return;
-		UMaterialInstanceConstant* MI = Assets.Object();
-
-		// Determine the parameter type -- explicit or auto-detect from parent
-		FString TypeStr = Type;
-		if (TypeStr.IsEmpty())
-			TypeStr = AutoDetectType(MI);
-
-		if (TypeStr.IsEmpty())
-		{
-			Result.Appendf(TEXT("ERROR: Could not determine parameter type for '%s'. Specify the 'type' field explicitly (scalar, vector, texture, staticSwitch).\n"),
-				*ParameterName);
-			return;
-		}
-
-		FMaterialParameterInfo ParamInfo(*ParameterName);
-		FString NewValueDescription;
-
-		if (TypeStr.Equals(TEXT("scalar"), ESearchCase::IgnoreCase))
-		{
-			double FloatValue = Json->GetNumberField(TEXT("value"));
-			if (!DryRun)
-				MI->SetScalarParameterValueEditorOnly(ParamInfo, (float)FloatValue);
-			NewValueDescription = FString::Printf(TEXT("%g"), FloatValue);
-		}
-		else if (TypeStr.Equals(TEXT("vector"), ESearchCase::IgnoreCase))
-		{
-			const TSharedPtr<FJsonObject>* ValueObj = nullptr;
-			if (!Json->TryGetObjectField(TEXT("value"), ValueObj) || !ValueObj || !(*ValueObj).IsValid())
-			{
-				Result.Append(TEXT("ERROR: For vector parameters, 'value' must be an object with r, g, b (and optional a) fields.\n"));
-				return;
-			}
-
-			double R = (*ValueObj)->GetNumberField(TEXT("r"));
-			double G = (*ValueObj)->GetNumberField(TEXT("g"));
-			double B = (*ValueObj)->GetNumberField(TEXT("b"));
-			double A = (*ValueObj)->HasField(TEXT("a")) ? (*ValueObj)->GetNumberField(TEXT("a")) : 1.0;
-			FLinearColor Color((float)R, (float)G, (float)B, (float)A);
-
-			if (!DryRun)
-				MI->SetVectorParameterValueEditorOnly(ParamInfo, Color);
-			NewValueDescription = FString::Printf(TEXT("(%.3f, %.3f, %.3f, %.3f)"), R, G, B, A);
-		}
-		else if (TypeStr.Equals(TEXT("texture"), ESearchCase::IgnoreCase))
-		{
-			FString TexturePath = Json->GetStringField(TEXT("value"));
-			if (TexturePath.IsEmpty())
-			{
-				Result.Append(TEXT("ERROR: For texture parameters, 'value' must be a texture asset path string.\n"));
-				return;
-			}
-
-			MCPAssets<UTexture> TexAssets;
-			if (!TexAssets.Exact(TexturePath).AllContent().Errors(Result).ENone().ETwo().Load()) return;
-			UTexture* TextureObj = TexAssets.Object();
-
-			if (!DryRun)
-				MI->SetTextureParameterValueEditorOnly(ParamInfo, TextureObj);
-			NewValueDescription = MCPUtils::FormatName(TextureObj);
-		}
-		else if (TypeStr.Equals(TEXT("staticSwitch"), ESearchCase::IgnoreCase))
-		{
-			bool bSwitchValue = Json->GetBoolField(TEXT("value"));
-
-			if (!DryRun)
-			{
-				FStaticParameterSet StaticParams;
-				MI->GetStaticParameterValues(StaticParams);
-
-				bool bFound = false;
-				for (FStaticSwitchParameter& Param : StaticParams.StaticSwitchParameters)
-				{
-					if (Param.ParameterInfo.Name == FName(*ParameterName))
-					{
-						Param.Value = bSwitchValue;
-						Param.bOverride = true;
-						bFound = true;
-						break;
-					}
-				}
-
-				if (!bFound)
-				{
-					FStaticSwitchParameter NewParam;
-					NewParam.ParameterInfo.Name = FName(*ParameterName);
-					NewParam.Value = bSwitchValue;
-					NewParam.bOverride = true;
-					StaticParams.StaticSwitchParameters.Add(NewParam);
-				}
-
-				MI->UpdateStaticPermutation(StaticParams);
-			}
-			NewValueDescription = bSwitchValue ? TEXT("true") : TEXT("false");
-		}
-		else
-		{
-			Result.Appendf(TEXT("ERROR: Unknown parameter type '%s'. Valid types: scalar, vector, texture, staticSwitch\n"), *TypeStr);
-			return;
-		}
-
-		if (!DryRun)
-		{
-			MCPUtils::PreEdit({MI});
-			MCPUtils::PostEdit({MI});
-			MCPUtils::SaveGenericPackage(MI);
-		}
-
-		if (DryRun)
-			Result.Appendf(TEXT("[DRY RUN] Would set %s \"%s\" = %s on %s\n"), *TypeStr, *ParameterName, *NewValueDescription, *MCPUtils::FormatName(MI));
-		else
-			Result.Appendf(TEXT("Set %s \"%s\" = %s on %s\n"), *TypeStr, *ParameterName, *NewValueDescription, *MCPUtils::FormatName(MI));
-	}
-
-private:
-	// Auto-detect parameter type by examining the base material's expressions.
-	FString AutoDetectType(UMaterialInstanceConstant* MI)
-	{
-		UMaterial* BaseMat = MI->GetMaterial();
-		if (!BaseMat) return FString();
-
-		for (UMaterialExpression* Expr : BaseMat->GetExpressions())
-		{
-			if (!Expr) continue;
-			if (auto* SP = Cast<UMaterialExpressionScalarParameter>(Expr))
-			{
-				if (SP->ParameterName.ToString() == ParameterName)
-					return TEXT("scalar");
-			}
-			else if (auto* VP = Cast<UMaterialExpressionVectorParameter>(Expr))
-			{
-				if (VP->ParameterName.ToString() == ParameterName)
-					return TEXT("vector");
-			}
-			else if (auto* TP = Cast<UMaterialExpressionTextureSampleParameter2D>(Expr))
-			{
-				if (TP->ParameterName.ToString() == ParameterName)
-					return TEXT("texture");
-			}
-			else if (auto* SSP = Cast<UMaterialExpressionStaticSwitchParameter>(Expr))
-			{
-				if (SSP->ParameterName.ToString() == ParameterName)
-					return TEXT("staticSwitch");
-			}
-		}
-		return FString();
-	}
-};

Plugins/BlueprintMCP/Source/BlueprintMCP/Private/MCPUtils.cpp

@@ -1150,21 +1150,79 @@ void MCPUtils::PostEdit(const TArray<UObject*>& Objects)
 		GEditor->RedrawAllViewports();
 }
 
-TArray<MCPMaterialParameter> MCPUtils::MaterialParameters(UMaterialInstanceConstant *MI)
+
+TMap<FMaterialParameterInfo, FMaterialParameterMetadata> MCPUtils::GetMaterialParameters(UMaterialInterface* Material)
 {
-	TArray<MCPMaterialParameter> Results;
+	TMap<FMaterialParameterInfo, FMaterialParameterMetadata> Result;
-	UMaterial* BaseMat = MI->GetMaterial();
+	if (!Material) return Result;
-	if (!BaseMat) return Results;
+	TMap<FMaterialParameterInfo, FMaterialParameterMetadata> Temp;
-	for (UMaterialExpression* Expr : BaseMat->GetExpressions())
+	for (int32 i = 0; i < (int32)EMaterialParameterType::NumRuntime; i++)
 	{
-		if (!Expr || !Expr->bIsParameterExpression) continue;
+		Material->GetAllParametersOfType((EMaterialParameterType)i, Temp);
-		MCPMaterialParameter P;
+		Result.Append(Temp);
-		P.Name = Expr->GetParameterName();
+	}
-		if (P.Name.IsNone()) continue;
+	return Result;
-		if (!Expr->GetParameterValue(P.Metadata)) continue;
+}
-		Results.Add(P);
+
+bool MCPUtils::ParseMaterialParameterAssociation(const FString& Str, EMaterialParameterAssociation& OutAssociation, MCPErrorCallback Error)
+{
+	if (Str.Equals(TEXT("Global"), ESearchCase::IgnoreCase))
+		OutAssociation = GlobalParameter;
+	else if (Str.Equals(TEXT("Layer"), ESearchCase::IgnoreCase))
+		OutAssociation = LayerParameter;
+	else if (Str.Equals(TEXT("Blend"), ESearchCase::IgnoreCase))
+		OutAssociation = BlendParameter;
+	else
+	{
+		Error.SetError(FString::Printf(TEXT("Invalid ParameterAssociation '%s' (expected 'Global', 'Layer', or 'Blend')"), *Str));
+		return false;
+	}
+	return true;
+}
+
+void MCPUtils::FormatMaterialParameter(FStringBuilderBase& Result, const FMaterialParameterInfo& Info, const FMaterialParameterMetadata& Meta)
+{
+	// Association prefix for layer/blend parameters.
+	FString Prefix;
+	if (Info.Association == LayerParameter)
+		Prefix = FString::Printf(TEXT("[Layer %d] "), Info.Index);
+	else if (Info.Association == BlendParameter)
+		Prefix = FString::Printf(TEXT("[Blend %d] "), Info.Index);
+
+	switch (Meta.Value.Type)
+	{
+	case EMaterialParameterType::Scalar:
+		Result.Appendf(TEXT("  %sScalar \"%s\" = %g\n"), *Prefix, *Info.Name.ToString(), Meta.Value.AsScalar());
+		break;
+	case EMaterialParameterType::Vector:
+	{
+		FLinearColor C = Meta.Value.AsLinearColor();
+		Result.Appendf(TEXT("  %sVector \"%s\" = (R=%.3f, G=%.3f, B=%.3f, A=%.3f)\n"),
+			*Prefix, *Info.Name.ToString(), C.R, C.G, C.B, C.A);
+		break;
+	}
+	case EMaterialParameterType::DoubleVector:
+	{
+		FVector4d V = Meta.Value.AsVector4d();
+		Result.Appendf(TEXT("  %sDoubleVector \"%s\" = (%.3f, %.3f, %.3f, %.3f)\n"),
+			*Prefix, *Info.Name.ToString(), V.X, V.Y, V.Z, V.W);
+		break;
+	}
+	case EMaterialParameterType::Texture:
+	{
+		UTexture* Tex = Cast<UTexture>(Meta.Value.AsTextureObject());
+		Result.Appendf(TEXT("  %sTexture \"%s\" = %s\n"),
+			*Prefix, *Info.Name.ToString(), Tex ? *MCPUtils::FormatName(Tex) : TEXT("None"));
+		break;
+	}
+	case EMaterialParameterType::StaticSwitch:
+		Result.Appendf(TEXT("  %sStaticSwitch \"%s\" = %s\n"),
+			*Prefix, *Info.Name.ToString(), Meta.Value.AsStaticSwitch() ? TEXT("true") : TEXT("false"));
+		break;
+	default:
+		Result.Appendf(TEXT("  %sType%d \"%s\"\n"), *Prefix, (int)Meta.Value.Type, *Info.Name.ToString());
+		break;
 	}
-	return Results;
 }
 
 bool MCPUtils::SaveMaterialPackage(UMaterial* Material)

Plugins/BlueprintMCP/Source/BlueprintMCP/Public/MCPUtils.h

@@ -98,12 +98,6 @@ struct MCPErrorCallback
 	void SetError(const FString& Msg) const { Func(Msg); }
 };
 
-struct MCPMaterialParameter
-{
-	FName Name;
-	FMaterialParameterMetadata Metadata;
-};
-
 // Stateless utility functions used by MCP handlers and the MCP server.
 // This is effectively a namespace — all methods are static.
 class MCPUtils
@@ -285,8 +279,10 @@ public:
 	static void PreEdit(const TArray<UObject*>& Objects);
 	static void PostEdit(const TArray<UObject*>& Objects);
 
-	// ----- Material Instance -----
+	// ----- Material Parameters -----
-	static TArray<MCPMaterialParameter> MaterialParameters(UMaterialInstanceConstant *MI);
+	static TMap<FMaterialParameterInfo, FMaterialParameterMetadata> GetMaterialParameters(UMaterialInterface* Material);
+	static bool ParseMaterialParameterAssociation(const FString& Str, EMaterialParameterAssociation& OutAssociation, MCPErrorCallback Error = nullptr);
+	static void FormatMaterialParameter(FStringBuilderBase& Result, const FMaterialParameterInfo& Info, const FMaterialParameterMetadata& Meta);
 
 	// ----- Editable template -----
 	// Given an object, returns the appropriate template object for generic