Code Help; GetUsedTextures Exposed to Blueprints

Unreal Engine Rendering
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#1

Hello,

I am just starting out on Unreal and C++, and am trying to expose to blueprints the UMaterial::GetUsedTextures function. My intent is to create a blueprint node that inputs a material and outputs a texture array.

I was following Rama’s documentation on this - but I just can’t seem to get it right.

I’ve created a blueprintfunction library, titled “GetUsedTextures” (Probably not the best idea to name my function library the same as the function I want to expose.)

Heres my code, if anyone could help me out that would be great! Thank you!

Header

#pragma once

#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "Material.h"
#include "GetUsedTextures.generated.h"


/**
 * 
 */
UCLASS()
class UNREALVRTEMPLATE_API UGetUsedTextures : public UBlueprintFunctionLibrary
{
	GENERATED_BODY()


	UFUNCTION(BlueprintCallable, Category = CustomBlueprint)
		array TexturesFunction(TArray < UTextures * >& OutTextures, UMaterial* GrabbingMaterial);

}

CPP

#include "UnrealVRTemplate.h"
#include "Material.h"
#include "GetUsedTextures.h"


array GetUsedTextures::TexturesFunction(TArray < UTextures * >& OutTextures, UMaterial* GrabbingMaterial)
{
	UMaterial::GetUsedTextures(TArray <UTexture *> & OutTextures);
		return OutTextures;
}

Thank you!

#2

Working some more on it - believe I’ve made progress. Searching through the code I found PrimitiveComponent.h uses the same function I want to use. I copied its code but I’m still kicking up an error - I believe it has something to do with my UFunction.

Getting only one error now (yay). (:Error: TheFunctions.h(21) : Error: Cannot find class ‘’, to resolve delegate ‘Type’).

h file

#pragma once

#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "Materials/Material.h"
#include "TheFunctions.generated.h"

/**
 * 
 */
UCLASS()
class UNREALVRTEMPLATE_API UTheFunctions : public UBlueprintFunctionLibrary
{
	GENERATED_BODY()

		virtual void GetUsedMaterials(TArray<UMaterialInterface*>& OutMaterials, bool bGetDebugMaterials = false) const {}

		UFUNCTION(BlueprintPure, Category = "CustomBlueprints,Materials")
		void GetUsedTextures(TArray<UTexture*>& OutTextures, EMaterialQualityLevel::Type QualityLevel);
	
};

cpp

#include "UnrealVRTemplate.h"
#include "Materials/Material.h"
#include "TheFunctions.h"

void UTheFunctions::GetUsedTextures(TArray<UTexture*>& OutTextures, EMaterialQualityLevel::Type QualityLevel)
{
	// Get the used materials so we can get their textures
	TArray<UMaterialInterface*> UsedMaterials;
	GetUsedMaterials(UsedMaterials);

	TArray<UTexture*> UsedTextures;
	for (int32 MatIndex = 0; MatIndex < UsedMaterials.Num(); ++MatIndex)
	{
		// Ensure we don't have any NULL elements.
		if (UsedMaterials[MatIndex])
		{
			auto World = GetWorld();

			UsedTextures.Reset();
			UsedMaterials[MatIndex]->GetUsedTextures(UsedTextures, QualityLevel, false, World ? World->FeatureLevel : GMaxRHIFeatureLevel, false);

			for (int32 TextureIndex = 0; TextureIndex<UsedTextures.Num(); TextureIndex++)
			{
				OutTextures.AddUnique(UsedTextures[TextureIndex]);
			}
		}
	}
}
#3

UFUNCTION(BlueprintCallable, Category = “CustomFunctions”)
static void GetUsedTextures(UMaterial* Material, TArray<UTexture*>& OutTextures);

void UTheFunctions::GetUsedTextures(UMaterial* Material, TArray<UTexture*>& OutTextures)
{
	//adjust if needed
	Material->GetUsedTextures(OutTextures, EMaterialQualityLevel::High, true, ERHIFeatureLevel::SM5, true);
}
#4

Nachtmahr,

Thank you so much for your help! That answer worked perfectly and clued me into referencing functions.

Cheers!

#5

Hello,

Can anyone help me?

#6

Hello again - could anyone point me in the right direction?