4.25 Transition Guide

[Rama]

Dear Community,

4.25 is here! Wohoo!

Please post your questions about the upgrade to 4.25 here, and also any compile errors you resolve on your own so that others may benefit.

Thank You Epic for 4.25!

♥

Rama

~~~

Reminder: If you are unable to compile after edits to your project or plugin C++ code:

"Command line is too long to fit in debug record"

https://developercommunity.visualstu...happening.html

Simply add this line to the build.cs:

bLegacyPublicIncludePaths = false;

~~~

UObjectProperty Becomes FObjectProperty

(BrUnO XaVIeR explains more below!)

UObjectProperty* ObjProp = Cast<UObjectProperty>(Property);

becomes

FObjectProperty* ObjProp = CastField<FObjectProperty>(Property);

~~~

Happy Coding!

♥

Rama

[BrUnO XaVIeR]

UProperty and all subclasses are not UObjects anymore...


A weak pointer went from

TWeakObjectPtr<UProperty> myProperty;

to

TWeakFieldPtr<FProperty> myProperty;

---

You can still use

FProperty::StaticClass();

and

myProperty->IsA( FxxxProperty::StaticClass() )

---

You can't use anymore

myProperty->GetOuter();

you have to use instead

myProperty->GetOwner<UObject>();

---

You can't use Cast<> on FProperties like before

CastChecked<UStructProperty>(myProperty);

Now you have to use a different one:

CastFieldChecked<FStructProperty>(myProperty);

[tommybazar]

1)
FImageWriteTask now accepts TArray64 as data instead of a TArray. If you have a regular TArray, pass it in like this:

TArray<FColor> OutBMP;
// Fill OutBMP somehow
TUniquePtr<TImagePixelData<FColor>> PixelData = MakeUnique<TImagePixelData<FColor>>(DestSize);
PixelData->Pixels = OutBMP;
ImageTask->PixelData = MoveTemp(PixelData);

---

2)
Shaders no longer have an explicit

virtual bool Serialize(FArchive& Ar) override

method to serialize.

This is now instead achieved by wrapping all shader parameters in a LAYOUT_FIELD macro.

FShaderResourceParameter ReadBuffer // Old declaration
LAYOUT_FIELD(FShaderResourceParameter, ReadBuffer); // New declaration

For the LAYOUT_FIELD macro to work, the shader needs to be declared with the DECLARE_SHADER_TYPE macro (which most shaders probably have, see side note below).

---

2b)
Side note for people using inheritance with shaders (probably not a huge subset of people) :

Using the normal macros for shader declare/implement breaks inheritance with virtual functions in shaders.
Got this to work - if you have a shader that's intended only as a parent shader (not to be implemented) with virtual methods, you have to call

  DECLARE_EXPORTED_TYPE_LAYOUT(FYourShaderName, YOUR_API, Virtual);

within the shader declaration and in a .cpp somewhere do

IMPLEMENT_UNREGISTERED_TEMPLATE_TYPE_LAYOUT(, FYourShaderName);

And in shaders with virtual methods (where the shader will be implemented), you have to call

  INTERNAL_DECLARE_SHADER_TYPE_COMMON(FYourSecondShaderName, Global, YOUR_API);
  DECLARE_EXPORTED_TYPE_LAYOUT(FYourSecondShaderName, YOUR_API, Virtual);

in the class declaration and standard IMPLEMENT_GLOBAL_SHADER in a cpp somewhere.

With this setup, it seems the serialization of shaders works fine with virtual methods too.
Not sure why Epic decided that you won't ever need a virtual memory layout with shaders (their regular macros assume it, see DECLARE_EXPORTED_SHADER_TYPE).

---

[Saragan]

Tried 3 computers, 3 fresh installations, 2 different migrated projects and 3 new projects on each pc with steam open and I cannot get steam subsystem to load, no overlay etc. think its broken

i did check i had steam > in game overlays turned on. was there any changes/new parameters that need changed to get it to work again?

this is tied to forum post https://forums.unrealengine.com/deve...25-steam-issue

[Bencsizy]

1)
Text

Any idea for macros like "GETSAFERHISHADER_VERTEX"? They were completely removed.

[UnrealXinda]

1)
FImageWriteTask now accepts TArray64 as data instead of a TArray. If you have a regular TArray, pass it in like this:

TArray<FColor> OutBMP;
// Fill OutBMP somehow
TUniquePtr<TImagePixelData<FColor>> PixelData = MakeUnique<TImagePixelData<FColor>>(DestSize);
PixelData->Pixels = OutBMP;
ImageTask->PixelData = MoveTemp(PixelData);

---

2)
Shaders no longer have an explicit

virtual bool Serialize(FArchive& Ar) override

method to serialize.

This is now instead achieved by wrapping all shader parameters in a LAYOUT_FIELD macro.

FShaderResourceParameter ReadBuffer // Old declaration
LAYOUT_FIELD(FShaderResourceParameter, ReadBuffer); // New declaration

For the LAYOUT_FIELD macro to work, the shader needs to be declared with the DECLARE_SHADER_TYPE macro (which most shaders probably have, see side note below).

---

2b)
Side note for people using inheritance with shaders (probably not a huge subset of people) :

Using the normal macros for shader declare/implement breaks inheritance with virtual functions in shaders.
Got this to work - if you have a shader that's intended only as a parent shader (not to be implemented) with virtual methods, you have to call

 DECLARE_EXPORTED_TYPE_LAYOUT(FYourShaderName, YOUR_API, Virtual);

within the shader declaration and in a .cpp somewhere do

IMPLEMENT_UNREGISTERED_TEMPLATE_TYPE_LAYOUT(, FYourShaderName);

And in shaders with virtual methods (where the shader will be implemented), you have to call

INTERNAL_DECLARE_SHADER_TYPE_COMMON(FYourSecondShaderName, Global, YOUR_API);
DECLARE_EXPORTED_TYPE_LAYOUT(FYourSecondShaderName, YOUR_API, Virtual);

in the class declaration and standard IMPLEMENT_GLOBAL_SHADER in a cpp somewhere.

With this setup, it seems the serialization of shaders works fine with virtual methods too.
Not sure why Epic decided that you won't ever need a virtual memory layout with shaders (their regular macros assume it, see DECLARE_EXPORTED_SHADER_TYPE).

---

Thanks! This is super helpful. Also it seems that the old helper functions like GetComputeShader() are gone from FShader. Do you have any insights on how to migrate from there?

[tommybazar]

Thanks! This is super helpful. Also it seems that the old helper functions like GetComputeShader() are gone from FShader. Do you have any insights on how to migrate from there?

It's been just changed a little bit. This works:

  TShaderMapRef<FYourShaderName> ComputeShader(GetGlobalShaderMap(ERHIFeatureLevel::SM5));
  FRHIComputeShader* pShaderRHI = ComputeShader.GetComputeShader();
  RHICmdList.SetComputeShader(pShaderRHI);

Any idea for macros like "GETSAFERHISHADER_VERTEX"? They were completely removed.

Those I haven't been using, try lurking through commits to the file where they were defined on Epic github. It's always an adventure with a new version

[UnrealXinda]

It's been just changed a little bit. This works:

TShaderMapRef<FYourShaderName> ComputeShader(GetGlobalShaderMap(ERHIFeatureLevel::SM5));
FRHIComputeShader* pShaderRHI = ComputeShader.GetComputeShader();
RHICmdList.SetComputeShader(pShaderRHI);

OK. So like we can no longer call GetComputeShader() from inside custom shader now? Cause I used to do things like

class FMyShader : public FGlobalShader
{
...
    void BindShaderBuffer(FRHICommandList& RHICmdList, FUnorderedAccessViewRHIRef OutputBufferUAV)
    {
        SetUAVParameter(RHICmdList, GetComputeShader(), OutputBuffer, OutputBufferUAV);
    }
}

[tommybazar]

OK. So like we can no longer call GetComputeShader() from inside custom shader now? Cause I used to do things like.........

Use this:

RHICmdList.GetBoundComputeShader();

[Bencsizy]

TShaderMapRef<FYourShaderName> ComputeShader(GetGlobalShaderMap(ERHIFeatureLevel::SM5));
FRHIComputeShader* pShaderRHI = ComputeShader.GetComputeShader();
RHICmdList.SetComputeShader(pShaderRHI);

For me, it says GetComputerShader is not a member of my class. It means DECLARE_SHADER_TYPE and IMPLEMENT_SHADER_TYPE does not work correctly anymore?

[UnrealXinda]

For me, it says GetComputerShader is not a member of my class. It means DECLARE_SHADER_TYPE and IMPLEMENT_SHADER_TYPE does not work correctly anymore?

I confirm that the code tommybazar posted does work. Note that it's not dereferencing from ComputeShader, it's actually accessing the member function GetComputeShader of TShaderMapRef. So instead of the old ComputeShader->GetComputeShader(), it's now ComputeShader.GetComputeShader();

[getnamo]

If you were using

UProperty*

for wildcard property passing in Blueprint, the transition that worked for me was

TFieldPath<FProperty>

e.g.

UFUNCTION(BlueprintCallable, CustomThunk, meta = (CustomStructureParam = "AnyStruct"))
static bool ReadAnyStruct(TFieldPath<FProperty> AnyStruct);

Also in my case, stepping through a custom thunk,

ExactCast

became

CastField

e.g.

FStructProperty* StructProp = CastField<FStructProperty>(Stack.MostRecentProperty);

[ANameTooLongToFi]

In case someone runs into this problem,
FImageWrapperBase now uses MoveTemp for its GetRaw, which means that you can't use an rvalue for the RawData, and the overridden GetRaw for IImageWrapper was changed to use a TArray64.

Example of the change:

TArray<uint8> *RawDataPtr = NULL;
TArray<uint8>& RawData = *RawDataPtr;
if (ImageWrapper->GetRaw(ERGBFormat::RGBA, 8, RawData))

Should be changed to:

TArray64<uint8> *RawData;
if (ImageWrapper->GetRaw(ERGBFormat::RGBA, 8, RawData))

I ran into this issue because I was using ImageWrapper for a UTexture2DDynamic.

[unit23]

Any ideas how to fix this kind of error:

Assertion failed: !Obj->HasAnyFlags(RF_NeedLoad) [File:D:/Build/++UE4+Licensee/Sync/Engine/Source/Runtime/Engine/Private/Animation/AnimCompressionTypes.cpp] [Line: 403] Failed to load AnimBoneCompressionSettings /Engine/Animation/DefaultAnimBoneCompressionSettings.DefaultAnimBoneCompressionSettings in AnimSequence /Game/Run/Animations/Movement/Idle.Idle

AnimCompressionTypes.cpp at 403 https://github.com/EpicGames/UnrealE...ssionTypes.cpp

 
template void FUECompressedAnimData::ByteSwapData(TArrayView<uint8> CompressedData, FMemoryReader& MemoryStream);


template void FUECompressedAnimData::ByteSwapData(TArrayView<uint8> CompressedData, FMemoryWriter& MemoryStream);





void ValidateUObjectLoaded(UObject* Obj, UObject* Source)


{


#if WITH_EDITOR


if (FLinkerLoad* ObjLinker = Obj->GetLinker())


{


ObjLinker->Preload(Obj);


}


#endif


checkf(!Obj->HasAnyFlags(RF_NeedLoad), TEXT("Failed to load %s in %s"), *Obj->GetFullName(), *Source->GetFullName()); // in non editor should have been preloaded by GetPreloadDependencies


}

Looks like GetPreloadDependencies is not properly preloading?

[mjdm61]

I'm having problems with mouse over events on static mesh components via OnBeginCursorOver and OnEndCursorOver and OnClicked.

I have code which has worked over all recent versions up to 4.24.2, but the identical code does not work under 4.25.

The relevant parts are:

[Header file]

UFUNCTION(BlueprintCallable, Category = ViewPoint)
void BlockClicked(UPrimitiveComponent* ClickedComp,FKey key);

UFUNCTION(BlueprintCallable, Category = ViewPoint)
void BlockBeginMouseOver(UPrimitiveComponent* ClickedComp);

UFUNCTION(BlueprintCallable, Category = ViewPoint)
void BlockEndMouseOver(UPrimitiveComponent* ClickedComp);

[Constructor]

// Create dummy root scene component
DummyRoot = CreateDefaultSubobject<USceneComponent>(TEXT("Dummy0"));

// Structure to hold one-time initialization
struct FConstructorStatics
{
ConstructorHelpers::FObjectFinderOptional<UStaticMesh> ViewPointMesh;
FConstructorStatics(): ViewPointMesh(TEXT("/Game/Meshes/ViewPointMarker.ViewPointMarker"))
{
}
};
static FConstructorStatics ConstructorStatics;

// Create static mesh component
BlockMesh = CreateDefaultSubobject<UStaticMeshComponent>(TEXT("BlockMesh0"));
BlockMesh->SetStaticMesh(ConstructorStatics.ViewPointMesh.Get());
BlockMesh->AttachTo(DummyRoot);



//React to mouse clicks
BlockMesh->OnBeginCursorOver.AddDynamic(this, &AViewPoint::BlockBeginMouseOver);
BlockMesh->OnEndCursorOver.AddDynamic(this, &AViewPoint::BlockEndMouseOver);
BlockMesh->OnClicked.AddDynamic(this, &AViewPoint::BlockClicked);

[Functions]

void AViewPoint::BlockClicked(UPrimitiveComponent* ClickedComp,FKey key)
{

if (GEngine)
{
FString message1 = TEXT("BlockClicked ViewPoint Called...");
GEngine->AddOnScreenDebugMessage(-1, 2.f, FColor::Yellow, message1);
}

}



void AViewPoint::BlockBeginMouseOver(UPrimitiveComponent* ClickedComp)
{

if (GEngine)
{

FString message = TEXT("BlockBeginMouseOver ViewPoint Called...");
GEngine->AddOnScreenDebugMessage(-1, 2.f, FColor::Yellow, message);

APlayerController* MyController = GetWorld()->GetFirstPlayerController();
MyController->CurrentMouseCursor = EMouseCursor::Hand;

}

}



void AViewPoint::BlockEndMouseOver(UPrimitiveComponent* ClickedComp)
{

if (GEngine)
{
FString message = TEXT("BlockEndMouseOver ViewPoint Called...");
GEngine->AddOnScreenDebugMessage(-1, 2.f, FColor::Red, message);

APlayerController* MyController = GetWorld()->GetFirstPlayerController();
MyController->CurrentMouseCursor = MyController->DefaultMouseCursor;

}


}

I am finding that unlike in 4.24.2, in 4.25, the static mesh does not react when hovering the mouse over it. Also, when I click the left mouse button, the OnClicked event isn't called. When I release the left mouse button however, both the BeginMouseOver and EndMouseOver events are called.

Has something changed in 4.25?