Files
UnrealEngine/Engine/Source/Editor/BlueprintGraph/Private/BlueprintEventNodeSpawner.cpp
2025-05-18 13:04:45 +08:00

270 lines
9.3 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#include "BlueprintEventNodeSpawner.h"
#include "BlueprintNodeTemplateCache.h"
#include "Containers/Array.h"
#include "Delegates/Delegate.h"
#include "EdGraph/EdGraph.h"
#include "EdGraph/EdGraphNode.h"
#include "EdGraph/EdGraphPin.h"
#include "EdGraphSchema_K2.h"
#include "Engine/Blueprint.h"
#include "Engine/MemberReference.h"
#include "HAL/Platform.h"
#include "HAL/PlatformCrt.h"
#include "Internationalization/Internationalization.h"
#include "Internationalization/Text.h"
#include "K2Node_CallFunction.h"
#include "K2Node_Event.h"
#include "K2Node_FunctionEntry.h"
#include "Kismet2/BlueprintEditorUtils.h"
#include "Misc/AssertionMacros.h"
#include "Styling/AppStyle.h"
#include "Templates/Casts.h"
#include "Textures/SlateIcon.h"
#include "UObject/Class.h"
#include "UObject/Package.h"
class UObject;
#define LOCTEXT_NAMESPACE "BlueprintEventNodeSpawner"
/*******************************************************************************
* Static UBlueprintEventNodeSpawner Helpers
******************************************************************************/
namespace UBlueprintEventNodeSpawnerImpl
{
/**
* Helper function for removing a ghost node (and connected ghost nodes, e.g., an autogenerated super call)
*
* @param InNode The node to start with
* @param InParentGraph The graph to remove the nodes from
*/
static void RemoveGhostNodes(UEdGraphNode* InNode, UEdGraph* InParentGraph);
}
//------------------------------------------------------------------------------
static void UBlueprintEventNodeSpawnerImpl::RemoveGhostNodes(UEdGraphNode* InNode, UEdGraph* InParentGraph)
{
if(InNode && InNode->IsAutomaticallyPlacedGhostNode())
{
// Go through all pin connections and consume any disabled nodes so we do not leave garbage.
for (UEdGraphPin* Pin : InNode->Pins)
{
TArray<UEdGraphPin*> LinkedToCopy = Pin->LinkedTo;
for (UEdGraphPin* OtherPin : LinkedToCopy)
{
// Break the pin link back
OtherPin->BreakLinkTo(Pin);
RemoveGhostNodes(OtherPin->GetOwningNode(), InParentGraph);
}
}
InNode->BreakAllNodeLinks();
InParentGraph->RemoveNode(InNode);
}
};
/*******************************************************************************
* UBlueprintEventNodeSpawner
******************************************************************************/
//------------------------------------------------------------------------------
UBlueprintEventNodeSpawner* UBlueprintEventNodeSpawner::Create(UFunction const* const EventFunc, UObject* Outer/* = nullptr*/)
{
check(EventFunc != nullptr);
if (Outer == nullptr)
{
Outer = GetTransientPackage();
}
UBlueprintEventNodeSpawner* NodeSpawner = NewObject<UBlueprintEventNodeSpawner>(Outer);
NodeSpawner->EventFunc = EventFunc;
NodeSpawner->NodeClass = UK2Node_Event::StaticClass();
FBlueprintActionUiSpec& MenuSignature = NodeSpawner->DefaultMenuSignature;
FText const FuncName = UEdGraphSchema_K2::GetFriendlySignatureName(EventFunc);
MenuSignature.MenuName = FText::Format(LOCTEXT("EventWithSignatureName", "Event {0}"), FuncName);
MenuSignature.Category = UK2Node_CallFunction::GetDefaultCategoryForFunction(EventFunc, LOCTEXT("AddEventCategory", "Add Event"));
//MenuSignature.Tooltip, will be pulled from the node template
MenuSignature.Keywords = UK2Node_CallFunction::GetKeywordsForFunction(EventFunc);
if (MenuSignature.Keywords.IsEmpty())
{
MenuSignature.Keywords = FText::FromString(TEXT(" "));
}
MenuSignature.Icon = FSlateIcon(FAppStyle::GetAppStyleSetName(), "GraphEditor.Event_16x");
return NodeSpawner;
}
//------------------------------------------------------------------------------
UBlueprintEventNodeSpawner* UBlueprintEventNodeSpawner::Create(TSubclassOf<UK2Node_Event> NodeClass, FName CustomEventName, UObject* Outer/* = nullptr*/)
{
if (Outer == nullptr)
{
Outer = GetTransientPackage();
}
UBlueprintEventNodeSpawner* NodeSpawner = NewObject<UBlueprintEventNodeSpawner>(Outer);
NodeSpawner->NodeClass = NodeClass;
NodeSpawner->CustomEventName = CustomEventName;
FBlueprintActionUiSpec& MenuSignature = NodeSpawner->DefaultMenuSignature;
if (CustomEventName.IsNone())
{
MenuSignature.MenuName = LOCTEXT("AddCustomEvent", "Add Custom Event...");
MenuSignature.Icon = FSlateIcon(FAppStyle::GetAppStyleSetName(), "GraphEditor.CustomEvent_16x");
}
else
{
FText const EventName = FText::FromName(CustomEventName);
MenuSignature.MenuName = FText::Format(LOCTEXT("EventWithSignatureName", "Event {0}"), EventName);
MenuSignature.Icon = FSlateIcon(FAppStyle::GetAppStyleSetName(), "GraphEditor.Event_16x");
}
//MenuSignature.Category, will be pulled from the node template
//MenuSignature.Tooltip, will be pulled from the node template
//MenuSignature.Keywords, will be pulled from the node template
return NodeSpawner;
}
//------------------------------------------------------------------------------
UBlueprintEventNodeSpawner::UBlueprintEventNodeSpawner(FObjectInitializer const& ObjectInitializer)
: Super(ObjectInitializer)
, EventFunc(nullptr)
{
}
//------------------------------------------------------------------------------
FBlueprintNodeSignature UBlueprintEventNodeSpawner::GetSpawnerSignature() const
{
FBlueprintNodeSignature SpawnerSignature(NodeClass);
if (IsForCustomEvent() && !CustomEventName.IsNone())
{
static const FName CustomSignatureKey(TEXT("CustomEvent"));
SpawnerSignature.AddNamedValue(CustomSignatureKey, CustomEventName.ToString());
}
else
{
SpawnerSignature.AddSubObject(const_cast<UFunction*>(ToRawPtr(EventFunc)));
}
return SpawnerSignature;
}
//------------------------------------------------------------------------------
UEdGraphNode* UBlueprintEventNodeSpawner::Invoke(UEdGraph* ParentGraph, FBindingSet const& Bindings, FVector2D const Location) const
{
check(ParentGraph != nullptr);
UBlueprint* Blueprint = FBlueprintEditorUtils::FindBlueprintForGraphChecked(ParentGraph);
UK2Node_Event* EventNode = nullptr;
if (!FBlueprintNodeTemplateCache::IsTemplateOuter(ParentGraph))
{
// look to see if a node for this event already exists (only one node is
// allowed per event, per blueprint)
UK2Node_Event const* PreExistingNode = FindPreExistingEvent(Blueprint, Bindings);
// @TODO: casting away the const is bad form!
EventNode = const_cast<UK2Node_Event*>(PreExistingNode);
}
bool const bIsCustomEvent = IsForCustomEvent();
check(bIsCustomEvent || (EventFunc != nullptr));
FName EventName = CustomEventName;
if (!bIsCustomEvent)
{
EventName = EventFunc->GetFName();
}
// If there is a function with this name on the blueprint, focus on that instead
for (UEdGraph* FuncGraph : Blueprint->FunctionGraphs)
{
if (FuncGraph && FuncGraph->GetFName() == EventName)
{
TArray<UK2Node_FunctionEntry*> FunctionEntry;
FuncGraph->GetNodesOfClass<UK2Node_FunctionEntry>(FunctionEntry);
if (FunctionEntry.Num())
{
return FunctionEntry[0];
}
else
{
return nullptr;
}
}
}
// This Event node might already be present in the Blueprint in a disabled state,
// remove it and allow the user to successfully place the node where they want it.
if(EventNode && EventNode->IsAutomaticallyPlacedGhostNode())
{
UBlueprintEventNodeSpawnerImpl::RemoveGhostNodes(EventNode, ParentGraph);
EventNode = nullptr;
}
// if there is no existing node, then we can happily spawn one into the graph
if (EventNode == nullptr)
{
auto PostSpawnLambda = [](UEdGraphNode* NewNode, bool bInIsTemplateNode, UFunction const* InEventFunc, FName InEventName, FCustomizeNodeDelegate UserDelegate)
{
UK2Node_Event* K2EventNode = CastChecked<UK2Node_Event>(NewNode);
if (InEventFunc != nullptr)
{
K2EventNode->EventReference.SetFromField<UFunction>(InEventFunc, false);
K2EventNode->bOverrideFunction = true;
}
else if (!bInIsTemplateNode)
{
K2EventNode->CustomFunctionName = InEventName;
}
UserDelegate.ExecuteIfBound(NewNode, bInIsTemplateNode);
};
FCustomizeNodeDelegate PostSpawnDelegate = FCustomizeNodeDelegate::CreateStatic(PostSpawnLambda, ToRawPtr(EventFunc), EventName, CustomizeNodeDelegate);
EventNode = Super::SpawnNode<UK2Node_Event>(NodeClass, ParentGraph, Bindings, Location, PostSpawnDelegate);
}
// else, a node for this event already exists, and we should return that
// (the FBlueprintActionMenuItem should detect this and focus in on it).
return EventNode;
}
//------------------------------------------------------------------------------
UFunction const* UBlueprintEventNodeSpawner::GetEventFunction() const
{
return EventFunc;
}
//------------------------------------------------------------------------------
UK2Node_Event const* UBlueprintEventNodeSpawner::FindPreExistingEvent(UBlueprint* Blueprint, FBindingSet const& /*Bindings*/) const
{
UK2Node_Event* PreExistingNode = nullptr;
check(Blueprint != nullptr);
if (IsForCustomEvent())
{
PreExistingNode = FBlueprintEditorUtils::FindCustomEventNode(Blueprint, CustomEventName);
}
else
{
check(EventFunc != nullptr);
UClass* ClassOwner = EventFunc->GetOwnerClass()->GetAuthoritativeClass();
PreExistingNode = FBlueprintEditorUtils::FindOverrideForFunction(Blueprint, ClassOwner, EventFunc->GetFName());
}
return PreExistingNode;
}
//------------------------------------------------------------------------------
bool UBlueprintEventNodeSpawner::IsForCustomEvent() const
{
return (EventFunc == nullptr);
}
#undef LOCTEXT_NAMESPACE