AI Jump

[anonymous_user_3efb8d4c]

Hello!

I have Blueprint-only (Version 4.13) sidescroller project which im happy with until now (set up items, currency, movement, menus… - basic functionality of a game).

I have integrated some AI so it runs from point A to B. But it does not jump to a higher ground to continue running / chasing.

I researched that a jump is not doable with blueprints only. So I have tried to follow steps from this guide: A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums

I have also used the code from MieszkoZ github : GitHub - MieszkoZ/AITutorialCPP: Tutorial ground for showing how UE4 AI should be set up and used.

After setting up first class NavArea_Jump .h and .cpp and building it i got some errors but continued. (also used the code from github)

.h

// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.

#pragma once

#include “AI/Navigation/NavAreas/NavArea.h”
#include “NavArea_Jump.generated.h”

UENUM()
namespace ENavAreaFlag
{
// up to 15 values
enum Type
{
Default,
Jump,
Crouch,
// and what not
};
}

namespace FNavAreaHelper
{
FORCEINLINE bool IsSet(uint16 Flags, ENavAreaFlag::Type Bit) { return (Flags & (1 << Bit)) != 0; }
FORCEINLINE void Set(uint16& Flags, ENavAreaFlag::Type Bit) { Flags |= (1 << Bit); }

FORCEINLINE bool IsNavLink(const FNavPathPoint& PathVert) { return (FNavMeshNodeFlags(PathVert.Flags).PathFlags & RECAST_STRAIGHTPATH_OFFMESH_CONNECTION) != 0; }
FORCEINLINE bool HasJumpFlag(const FNavPathPoint& PathVert) { return IsSet(FNavMeshNodeFlags(PathVert.Flags).AreaFlags, ENavAreaFlag::Jump); }
FORCEINLINE bool HasCrouchFlag(const FNavPathPoint& PathVert) { return IsSet(FNavMeshNodeFlags(PathVert.Flags).AreaFlags, ENavAreaFlag::Crouch); }

}

UCLASS()
class UNavArea_Jump : public UNavArea
{
GENERATED_UCLASS_BODY()
};

.cpp

// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.

#include “AdTycoon.h”
#include “NavArea_Jump.h”

UNavArea_Jump::UNavArea_Jump(const FObjectInitializer& ObjectInitializer)
: Super(ObjectInitializer)
{
FNavAreaHelper::Set(AreaFlags, ENavAreaFlag::Jump);
}

Created a new C++ class TutorialPathFollowingComponent inside the engine as described in the tutorial. (also used the code from github)

.h

#pragma once

#include “Navigation/PathFollowingComponent.h”
#include “TutorialPathFollowingComponent.generated.h”

/**
*
*/
class UNavMovementComponent;
class UCharacterMovementComponent;

UCLASS()
class UTutorialPathFollowingComponent : public UPathFollowingComponent
{
GENERATED_BODY()

protected:
/** cached UCharacterMovementComponent /
UPROPERTY(transient)
UCharacterMovementComponent CharacterMoveComp;

public:
// used to detect properties of a path’s segment a character is about to follow
virtual void SetMoveSegment(int32 SegmentStartIndex) override;

// used to cache UCharacterMovementComponent we're using in SetMoveSegment implementation
virtual void SetMovementComponent(UNavMovementComponent* MoveComp) override;

};

.cpp

#include “AdTycoon.h”
#include “TutorialPathFollowingComponent.h”
#include “NavArea_Jump.h”

void UTutorialPathFollowingComponent::SetMoveSegment(int32 SegmentStartIndex)
{
Super::SetMoveSegment(SegmentStartIndex);

if (CharacterMoveComp != NULL)
{
	const FNavPathPoint& SegmentStart = Path->GetPathPoints()[MoveSegmentStartIndex];

	if (FNavAreaHelper::HasJumpFlag(SegmentStart))
	{
		// jump! well... fly-in-straight-line!
		CharacterMoveComp->SetMovementMode(MOVE_Flying);
	}
	else
	{
		// regular move
		CharacterMoveComp->SetMovementMode(MOVE_Walking);
	}
}

}

void UTutorialPathFollowingComponent::SetMovementComponent(UNavMovementComponent* MoveComp)
{
Super::SetMovementComponent(MoveComp);

CharacterMoveComp = Cast<UCharacterMovementComponent>(MovementComp);

}

Repeated the same process for the class TutorialAIController. (also used the code from github)

.h

#pragma once
#include “AIController.h”
#include “TutorialAIController.generated.h”
/**
*
*/
UCLASS()
class ADTYCOON_API ATutorialAIController : public AAIController
{
GENERATED_BODY()
public:
ATutorialAIController(const FObjectInitializer& ObjectInitializer);
};

.cpp

#include “AdTycoon.h”
#include “ATutorialAIController.h”
#include “TutorialPathFollowingComponent.h”

ATutorialAIController::ATutorialAIController(const FObjectInitializer& ObjectInitializer)
: Super(ObjectInitializer.SetDefaultSubobjectClass<UTutorialPathFollowingComponent>(TEXT(“PathFollowingComponent”)))
{

}

In the end I only see the class NavArea_Jump inside the game engine and I also get 4 errors after building in visual studio:

Severity Code Description Project File Line Suppression State
Error (active) identifier “FNavMeshNodeFlags” is undefined AdTycoon e:\AndroidProjects\Unreal Projects\AdTycoon\Source\AdTycoon\NavArea_Jump.h 26

Severity Code Description Project File Line Suppression State
Error (active) identifier “RECAST_STRAIGHTPATH_OFFMESH_CONNECTION” is undefined AdTycoon e:\AndroidProjects\Unreal Projects\AdTycoon\Source\AdTycoon\NavArea_Jump.h 26

Severity Code Description Project File Line Suppression State
Error (active) identifier “FNavMeshNodeFlags” is undefined AdTycoon e:\AndroidProjects\Unreal Projects\AdTycoon\Source\AdTycoon\NavArea_Jump.h 27

Severity Code Description Project File Line Suppression State
Error (active) identifier “FNavMeshNodeFlags” is undefined AdTycoon e:\AndroidProjects\Unreal Projects\AdTycoon\Source\AdTycoon\NavArea_Jump.h 28

Which are following lines in the class NavArea_Jump.h:

    FORCEINLINE bool IsNavLink(const FNavPathPoint& PathVert) { return (FNavMeshNodeFlags(PathVert.Flags).PathFlags & RECAST_STRAIGHTPATH_OFFMESH_CONNECTION) != 0; }
FORCEINLINE bool HasJumpFlag(const FNavPathPoint& PathVert) { return IsSet(FNavMeshNodeFlags(PathVert.Flags).AreaFlags, ENavAreaFlag::Jump); }
FORCEINLINE bool HasCrouchFlag(const FNavPathPoint& PathVert) { return IsSet(FNavMeshNodeFlags(PathVert.Flags).AreaFlags, ENavAreaFlag::Crouch); }

How can I fix it ? I would be thankfull for any hints !

I have also checked the guide from Rama : A new, community-hosted Unreal Engine Wiki - Announcements - Epic Developer Community Forums

But I got it right, that I would need to add a bunch of code to get it work ?

Thank you for reading !

Edit: I put an object beneath the spot i need the AI to jump. Works okeyish , sometimes too buggy though as the AI tries to run back and does not understand its being launched. Not the best workaround though

[anonymous_user_3efb8d4c]

Bump Still looking for a proper solution