How to read pixels form a UTexture?

Development Programming & Scripting
2

Well, UTexture is an abstract class that cannot be instantiated. It relies on it’s concrete subclasses UTexture2D, UTextureCube, UTexture2DArray, etc to be instantiated. If you have a pointer to a UTexture, then it actually IS a UTexture2D, or UTextureCube, or UTexture2DArray etc.

So what you can do i believe, is simply cast it like so.

if(const auto Texture2D = Cast<UTexture2D>(Texture))
{
    //If This block is reached, the texture was a Texture2D.  Lets do our work with it

	// Make Sure The Texture Is Up To Date.
	Texture2D->UpdateResource();

	// Get Platform Data.
	const auto PlatformData = Texture2D->GetPlatformData();
	
	// Get The Bulk Data
	const auto TextureData = PlatformData->Mips[0].BulkData;

	// Array Pixel Data Will Be Copied To
	TArray<FColor> DestPixels{};

	// Initialize The Array With The Correct Pixel Size;
	DestPixels.AddDefaulted(PlatformData->SizeX * PlatformData->SizeY);

	// Lock The Pixel Data For CPU Read Access.
	const auto PixelData = static_cast<const FColor*>(TextureData.LockReadOnly());

	// Copy The Pixel Data.
	FMemory::Memcpy(DestPixels.GetData(), &PixelData, sizeof(FColor) * DestPixels.Num());

	// Unlock So The GPU Can Access The Data Again.
	TextureData.Unlock();

	// We Now Have All Pixel Data For The Texture And We Can Do What We Want Without Holding The GPU Up.
	DestPixels
}
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