unreal engine 4 (ue4) 中带有自定义 c++ 蓝图函数库的蓝图 loop/for/while 节点
Blueprint loop/for/while node with custom c++ blueprint function library in unreal engine 4 (ue4)
我需要创建自定义蓝图节点。我用的是蓝图函数库
节点将如下所示:
输入:
int timedelayforeach循环
int numberofloops
输出:
exc循环
exc 完成
loop1.h
// Fill out your copyright notice in the Description page of Project Settings.
#pragma once
#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "loop1.generated.h"
/**
*
*/
UENUM(BlueprintType)
enum class EMultiBranchEnum1 : uint8
{
BranchA,
BranchB
};
UCLASS()
class MYPROJECT2_API Uloop1 : public UBlueprintFunctionLibrary
{
GENERATED_BODY()
UFUNCTION(BlueprintCallable, meta = (DisplayName = "loop", CompactNodeTitle = "2as2", ExpandEnumAsExecs = "Branches"), Category = "1")
//UFUNCTION(BlueprintCallable, Meta = (DisplayName = "Multi Branch1", ExpandEnumAsExecs = "Branches"), Category = 1)
static void multiBranch(EMultiBranchEnum1& Branches, int loopqty);
//EMultiBranchEnum1::BranchB;
};
loop1.cpp
// Fill out your copyright notice in the Description page of Project Settings.
#include "loop1.h"
void Uloop1::multiBranch(EMultiBranchEnum1& Branches, int loopqty)
{
int currloop1 = 0;
int temp = 2;
int i;
for (i = 0; i < 10; i++){
currloop1 = currloop1 + 1;
Branches = EMultiBranchEnum1::BranchA;
}
if (temp > currloop1) {
Branches = EMultiBranchEnum1::BranchB;
}
if(temp == 0) {
Branches = EMultiBranchEnum1::BranchB;
}
}
-- 问题 --
for 循环只有 运行 一次(我在 branchA 上的打印节点很明显(它只打印一次))
-- 下面的代码会发生什么 --
循环应该 运行 10 次(我的打印节点应该打印 10 次)
您应该使用 UBlueprintAsyncActionBase
而不是 UBlueprintFunctionLibrary
。它将允许您在节点中存储状态并异步调用连接到执行引脚的东西。
DelayLoop.h 文件:
#include "CoreMinimal.h"
#include "Kismet/BlueprintAsyncActionBase.h"
#include "DelayLoop.generated.h"
DECLARE_DYNAMIC_MULTICAST_DELEGATE(FDelayOutputPin);
/**
*
*/
UCLASS()
class TEST_API UDelayLoop : public UBlueprintAsyncActionBase
{
GENERATED_UCLASS_BODY()
public:
UPROPERTY(BlueprintAssignable)
FDelayOutputPin Loop;
UPROPERTY(BlueprintAssignable)
FDelayOutputPin Complete;
UFUNCTION(BlueprintCallable,
meta = (BlueprintInternalUseOnly = "true", WorldContext = "WorldContextObject"),
Category = "Flow Control")
static UDelayLoop* DelayLoop(const UObject* WorldContextObject,
const float DelayInSeconds, const int Iterations);
virtual void Activate() override;
private:
const UObject* WorldContextObject;
float MyDelay;
int MyIterations;
bool Active;
UFUNCTION()
void ExecuteLoop();
UFUNCTION()
void ExecuteComplete();
};
DelayLoop.cpp 文件:
#include "DelayLoop.h"
#include "Engine/World.h"
#include "TimerManager.h"
UDelayLoop::UDelayLoop(const FObjectInitializer& ObjectInitializer) :
Super(ObjectInitializer), WorldContextObject(nullptr), MyDelay(0.0f),
MyIterations(0), Active(false)
{
}
UDelayLoop* UDelayLoop::DelayLoop(const UObject* WorldContextObject,
const float DelayInSeconds, const int Iterations)
{
UDelayLoop* Node = NewObject<UDelayLoop>();
Node->WorldContextObject = WorldContextObject;
Node->MyDelay = DelayInSeconds;
Node->MyIterations = Iterations;
return Node;
}
void UDelayLoop::Activate()
{
if (nullptr == WorldContextObject)
{
FFrame::KismetExecutionMessage(TEXT("Invalid WorldContextObject."),
ELogVerbosity::Error);
return;
}
if (Active)
{
FFrame::KismetExecutionMessage(TEXT("DelayLoop is already running."),
ELogVerbosity::Warning);
}
if (MyDelay <= 0.0f)
{
FFrame::KismetExecutionMessage(
TEXT("DelayLoop delay can't be less or equal to 0."),
ELogVerbosity::Warning);
}
if (MyIterations <= 0)
{
FFrame::KismetExecutionMessage(
TEXT("DelayLoop iterations can't be less or equal to 0."),
ELogVerbosity::Warning);
}
Active = true;
for (int i = 0; i <= MyIterations; i++)
{
FTimerHandle IterationTimer;
WorldContextObject->GetWorld()->GetTimerManager().SetTimer(
IterationTimer, this, &UDelayLoop::ExecuteLoop, MyDelay * i);
}
FTimerHandle CompleteTimer;
WorldContextObject->GetWorld()->GetTimerManager().SetTimer(
CompleteTimer, this, &UDelayLoop::ExecuteComplete,
MyDelay * (MyIterations+1));
// If the Complete pin should happen at the same time as the last iteration
// use `MyDelay * MyIterations` here instead
}
void UDelayLoop::ExecuteLoop()
{
Loop.Broadcast();
}
void UDelayLoop::ExecuteComplete()
{
Complete.Broadcast();
Active = false;
}
这将为您提供如下所示的蓝图:
注意:此代码主要基于 This Creating Asynchronous Blueprint Nodes guide by Daniel ~b617 Janowski, now hosted in the legacy wiki here
我需要创建自定义蓝图节点。我用的是蓝图函数库
节点将如下所示:
输入: int timedelayforeach循环 int numberofloops
输出: exc循环 exc 完成
loop1.h
// Fill out your copyright notice in the Description page of Project Settings.
#pragma once
#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "loop1.generated.h"
/**
*
*/
UENUM(BlueprintType)
enum class EMultiBranchEnum1 : uint8
{
BranchA,
BranchB
};
UCLASS()
class MYPROJECT2_API Uloop1 : public UBlueprintFunctionLibrary
{
GENERATED_BODY()
UFUNCTION(BlueprintCallable, meta = (DisplayName = "loop", CompactNodeTitle = "2as2", ExpandEnumAsExecs = "Branches"), Category = "1")
//UFUNCTION(BlueprintCallable, Meta = (DisplayName = "Multi Branch1", ExpandEnumAsExecs = "Branches"), Category = 1)
static void multiBranch(EMultiBranchEnum1& Branches, int loopqty);
//EMultiBranchEnum1::BranchB;
};
loop1.cpp
// Fill out your copyright notice in the Description page of Project Settings.
#include "loop1.h"
void Uloop1::multiBranch(EMultiBranchEnum1& Branches, int loopqty)
{
int currloop1 = 0;
int temp = 2;
int i;
for (i = 0; i < 10; i++){
currloop1 = currloop1 + 1;
Branches = EMultiBranchEnum1::BranchA;
}
if (temp > currloop1) {
Branches = EMultiBranchEnum1::BranchB;
}
if(temp == 0) {
Branches = EMultiBranchEnum1::BranchB;
}
}
-- 问题 -- for 循环只有 运行 一次(我在 branchA 上的打印节点很明显(它只打印一次))
-- 下面的代码会发生什么 -- 循环应该 运行 10 次(我的打印节点应该打印 10 次)
您应该使用 UBlueprintAsyncActionBase
而不是 UBlueprintFunctionLibrary
。它将允许您在节点中存储状态并异步调用连接到执行引脚的东西。
DelayLoop.h 文件:
#include "CoreMinimal.h"
#include "Kismet/BlueprintAsyncActionBase.h"
#include "DelayLoop.generated.h"
DECLARE_DYNAMIC_MULTICAST_DELEGATE(FDelayOutputPin);
/**
*
*/
UCLASS()
class TEST_API UDelayLoop : public UBlueprintAsyncActionBase
{
GENERATED_UCLASS_BODY()
public:
UPROPERTY(BlueprintAssignable)
FDelayOutputPin Loop;
UPROPERTY(BlueprintAssignable)
FDelayOutputPin Complete;
UFUNCTION(BlueprintCallable,
meta = (BlueprintInternalUseOnly = "true", WorldContext = "WorldContextObject"),
Category = "Flow Control")
static UDelayLoop* DelayLoop(const UObject* WorldContextObject,
const float DelayInSeconds, const int Iterations);
virtual void Activate() override;
private:
const UObject* WorldContextObject;
float MyDelay;
int MyIterations;
bool Active;
UFUNCTION()
void ExecuteLoop();
UFUNCTION()
void ExecuteComplete();
};
DelayLoop.cpp 文件:
#include "DelayLoop.h"
#include "Engine/World.h"
#include "TimerManager.h"
UDelayLoop::UDelayLoop(const FObjectInitializer& ObjectInitializer) :
Super(ObjectInitializer), WorldContextObject(nullptr), MyDelay(0.0f),
MyIterations(0), Active(false)
{
}
UDelayLoop* UDelayLoop::DelayLoop(const UObject* WorldContextObject,
const float DelayInSeconds, const int Iterations)
{
UDelayLoop* Node = NewObject<UDelayLoop>();
Node->WorldContextObject = WorldContextObject;
Node->MyDelay = DelayInSeconds;
Node->MyIterations = Iterations;
return Node;
}
void UDelayLoop::Activate()
{
if (nullptr == WorldContextObject)
{
FFrame::KismetExecutionMessage(TEXT("Invalid WorldContextObject."),
ELogVerbosity::Error);
return;
}
if (Active)
{
FFrame::KismetExecutionMessage(TEXT("DelayLoop is already running."),
ELogVerbosity::Warning);
}
if (MyDelay <= 0.0f)
{
FFrame::KismetExecutionMessage(
TEXT("DelayLoop delay can't be less or equal to 0."),
ELogVerbosity::Warning);
}
if (MyIterations <= 0)
{
FFrame::KismetExecutionMessage(
TEXT("DelayLoop iterations can't be less or equal to 0."),
ELogVerbosity::Warning);
}
Active = true;
for (int i = 0; i <= MyIterations; i++)
{
FTimerHandle IterationTimer;
WorldContextObject->GetWorld()->GetTimerManager().SetTimer(
IterationTimer, this, &UDelayLoop::ExecuteLoop, MyDelay * i);
}
FTimerHandle CompleteTimer;
WorldContextObject->GetWorld()->GetTimerManager().SetTimer(
CompleteTimer, this, &UDelayLoop::ExecuteComplete,
MyDelay * (MyIterations+1));
// If the Complete pin should happen at the same time as the last iteration
// use `MyDelay * MyIterations` here instead
}
void UDelayLoop::ExecuteLoop()
{
Loop.Broadcast();
}
void UDelayLoop::ExecuteComplete()
{
Complete.Broadcast();
Active = false;
}
这将为您提供如下所示的蓝图:
注意:此代码主要基于 This Creating Asynchronous Blueprint Nodes guide by Daniel ~b617 Janowski, now hosted in the legacy wiki here