Trouble with Buoyancy

Development Programming & Scripting C++
1

Hi, I’m trying to recreate these tutorials., but I can’t for the life of me figure out the C++ part.

Header


#pragma once

#include "GameFramework/Actor.h"
#include "OceanManager.generated.h"

/**
 * 
 */
UCLASS()

class WASSER_API AOceanManager : public AActor
{
	GENERATED_UCLASS_BODY()

	UFUNCTION(BlueprintCallable, Category = "HeightMap|Texture Helper")
		FVector GetWaveHeightValue(FVector location, float time);

	UFUNCTION(BlueprintCallable, Category = "HeightMap|Texture Helper")
		FVector CalculateGerstnerWaveCluster(float medianWavelength, float medianAmplitude, FVector2D position, FVector2D medianDirection, float steepness, float time);

	UFUNCTION(BlueprintCallable, Category = "HeightMap|Texture Helper")
		FVector CalculateGerstnerWave(float wavelength, float amplitude, FVector2D position, FVector2D direction, float angle, float steepness, float time, float phase);

};

CPP


#include "Wasser.h"
#include "OceanManager.h"

FVector AOceanManager::GetWaveHeightValue(FVector location, float time)
{
	FVector sum = FVector(0, 0, 0);

	sum + -CalculateGerstnerWaveCluster(1000, 10, FVector2D(location.X, location.Y), FVector2D(0, 1), 0.5f, time);
	sum + -CalculateGerstnerWaveCluster(300, 7, FVector2D(location.X, location.Y), FVector2D(0, 1), 0.5f, time);

	return sum / 2;

}

FVector AOceanManager::CalculateGerstnerWaveCluster(float medianWavelength, float medianAmplitude, FVector2D position, FVector2D medianDirection, float steepness, float time)
{

	FVector sum = FVector(0, 0, 0);

	sum + -CalculateGerstnerWave(medianWavelength, medianAmplitude, position, medianDirection, 0, steepness, time, 0);
	sum + -CalculateGerstnerWave(medianWavelength * 0.5f, medianAmplitude * 0.5f, position, medianDirection, -0.1f, steepness, time, 0);
	sum + -CalculateGerstnerWave(medianWavelength * 2.0f, medianAmplitude * 2.0f, position, medianDirection, 0.1f, steepness, time, 0);
	sum + -CalculateGerstnerWave(medianWavelength * 1.25f, medianAmplitude * 1.25f, position, medianDirection, 0.05f, steepness, time, 0);
	sum + -CalculateGerstnerWave(medianWavelength * 0.75f, medianAmplitude * 0.75f, position, medianDirection, 0.075f, steepness, time, 0);
	sum + -CalculateGerstnerWave(medianWavelength * 1.5f, medianAmplitude * 1.5f, position, medianDirection, -0.125f, steepness, time, 0);
	sum + -CalculateGerstnerWave(medianWavelength * 0.825f, medianAmplitude * 0.825f, position, medianDirection, 0.063f, steepness, time, 0);
	sum + -CalculateGerstnerWave(medianWavelength * 0.65f, medianAmplitude * 0.65f, position, medianDirection, -0.11f, steepness, time, 0);

	return sum / 8;

}

FVector AOceanManager::CalculateGerstnerWave(float wavelength, float amplitude, FVector2D position, FVector2D direction, float angle, float steepness, float time, float phase)
{
	float lambda = (2 * PI) / wavelength;

	FVector dir = FVector(direction.X, direction.Y, 0);
	dir = dir.RotateAngleAxis(angle * 360, FVector(0, 0, 1));

	FVector2D rotatedDirection = FVector2D(dir.X, dir.Y);

	float wavePhase = lambda * FVector2D::DotProduct(rotatedDirection, position) + (time + phase);

	float c = FMath::Cos(wavePhase);
	float s = FMath::Sin(wavePhase);

	float QA = steepness * amplitude;

	return FVector(QA * rotatedDirection.X * c, QA * rotatedDirection.Y *  c, amplitude * s);

}

When I try to compile, I get this error:


Error    2    error LNK2019: unresolved external symbol "public: __cdecl AOceanManager::AOceanManager(class FPostConstructInitializeProperties const &)" (??0AOceanManager@@QEAA@AEBVFPostConstructInitializeProperties@@@Z) referenced in function "void __cdecl InternalConstructor<class AOceanManager>(class FPostConstructInitializeProperties const &)" (??$InternalConstructor@VAOceanManager@@@@YAXAEBVFPostConstructInitializeProperties@@@Z)    E:\UE4Projects\Wasser\Wasser\Intermediate\ProjectFiles\Wasser.generated.cpp.obj    Wasser

I hope someone can help me.

2

I think you need implementation constructor for AOceanManager.



AOceanManager::AOceanManager(const class FPostConstructInitializeProperties& PCIP) : Super(PCIP)
{
}
3

Here are my files for reference (if you want to use them as is, then you will need to rename MyGame to your project name).

OceanFunctionLibrary.h


#pragma once

#include "OceanFunctionLibrary.generated.h"

/**
 * 
 */
UCLASS()
class **MYGAME**_API UOceanFunctionLibrary : public UBlueprintFunctionLibrary
{
	GENERATED_UCLASS_BODY()

	UFUNCTION(BlueprintCallable, Category = "Gerstner Wave")
	static void GetWaveHeight(FVector PointLocation, float Time, float WaterPlaneHeight, float& WaveHeight);

protected:
	static float CalculateGerstnerWave(float wavelength, float amplitude, FVector2D position, FVector2D direction, float angle, float steepness, float time, float phase);
	static float CalculateGerstenrWaveCluster(float medianWavelength, float medianAmplitude, FVector2D position, FVector2D medianDirection, float steepness, float time);
};

OceanFunctionLibrary.cpp


#include "**MyGame**.h"
#include "OceanFunctionLibrary.h"


UOceanFunctionLibrary::UOceanFunctionLibrary(const class FPostConstructInitializeProperties& PCIP)
	: Super(PCIP)
{
}

void UOceanFunctionLibrary::GetWaveHeight(FVector PointLocation, float Time, float WaterPlaneHeight, float& WaveHeight)
{
	float sum = 0;

	sum += CalculateGerstenrWaveCluster(2500, 200, FVector2D(PointLocation.X, PointLocation.Y), FVector2D(0, 1), 0.5f, Time);
	sum += CalculateGerstenrWaveCluster(1000, 115, FVector2D(PointLocation.X, PointLocation.Y), FVector2D(0, 1), 0.5f, Time);

	WaveHeight = sum / 2 + WaterPlaneHeight;
}

float UOceanFunctionLibrary::CalculateGerstnerWave(float wavelength, float amplitude, FVector2D position, FVector2D direction, float angle, float steepness, float time, float phase)
{
	float lambda = (2 * PI) / wavelength;

	FVector dir = FVector(direction.X, direction.Y, 0);
	dir = dir.RotateAngleAxis(angle * 360, FVector(0, 0, 1));

	FVector2D rotatedDirection = FVector2D(dir.X, dir.Y);

	float wavePhase = lambda * FVector2D::DotProduct(rotatedDirection, position) + (time + phase);
	float s = FMath::Sin(wavePhase);

	return amplitude * s;
}

float UOceanFunctionLibrary::CalculateGerstenrWaveCluster(float medianWavelength, float medianAmplitude, FVector2D position, FVector2D medianDirection, float steepness, float time)
{
	float sum = 0;

	sum += CalculateGerstnerWave(medianWavelength, medianAmplitude, position, medianDirection, 0, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.5f, medianAmplitude * 0.5f, position, medianDirection, -0.1f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 2.0f, medianAmplitude * 2.0f, position, medianDirection, 0.1f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 1.25f, medianAmplitude * 1.25f, position, medianDirection, 0.05f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.75f, medianAmplitude * 0.75f, position, medianDirection, 0.075f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 1.5f, medianAmplitude * 1.5f, position, medianDirection, -0.125f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.825f, medianAmplitude * 0.825f, position, medianDirection, 0.063f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.65f, medianAmplitude * 0.65f, position, medianDirection, -0.11f, steepness, time, 0);

	return sum / 8;
}

Also I noticed in your code that also calculates x and y, which is unnecessary (and slower) for buoyancy code, which you only need Z.

4

Thanks for the help! The code seems to be working, but now I’m getting different errors:


Error	2	error : Failed to produce item: E:\Blueprint_Lampe_Schwebe\Binaries\Win64\UE4Editor-Lampe_Reife.pdb	E:\Blueprint_Lampe_Schwebe\Intermediate\ProjectFiles\ERROR	Lampe_Reife




Error	1	error LNK1104: cannot open file 'E:\Blueprint_Lampe_Schwebe\Binaries\Win64\UE4Editor-Lampe_Reife.dll'	E:\Blueprint_Lampe_Schwebe\Intermediate\ProjectFiles\LINK	Lampe_Reife




Error	3	error MSB3073: The command ""E:\Programme\Unreal Engine\4.4\Engine\Build\BatchFiles\Build.bat" Lampe_ReifeEditor Win64 Development "E:\Blueprint_Lampe_Schwebe\Lampe_Reife.uproject" -rocket" exited with code -1.	C:\Program Files (x86)\MSBuild\Microsoft.Cpp\v4.0\V120\Microsoft.MakeFile.Targets	38	5	Lampe_Reife

My Code now:

WaterManager.h




#pragma once

#include "GameFramework/Actor.h"
#include "WaterManager.generated.h"

/**
 * 
 */
UCLASS()
class LAMPE_REIFE_API AWaterManager : public AActor
{
	GENERATED_UCLASS_BODY()

		UFUNCTION(BlueprintCallable, Category = "Gerstner Wave")
		static void GetWaveHeight(FVector PointLocation, float Time, float WaterPlaneHeight, float& WaveHeight);

protected:
	static float CalculateGerstnerWave(float wavelength, float amplitude, FVector2D position, FVector2D direction, float angle, float steepness, float time, float phase);
	static float CalculateGerstnerWaveCluster(float medianWavelength, float medianAmplitude, FVector2D position, FVector2D medianDirection, float steepness, float time);
	
};

WaterManager.cpp




#include "Lampe_Reife.h"
#include "WaterManager.h"


AWaterManager::AWaterManager(const class FPostConstructInitializeProperties& PCIP)
	: Super(PCIP)
{

}

void AWaterManager::GetWaveHeight(FVector PointLocation, float Time, float WaterPlaneHeight, float& WaveHeight)
{
	float sum = 0;

	sum += CalculateGerstnerWaveCluster(2500, 200, FVector2D(PointLocation.X, PointLocation.Y), FVector2D(0, 1), 0.5f, Time);
	sum += CalculateGerstnerWaveCluster(1000, 115, FVector2D(PointLocation.X, PointLocation.Y), FVector2D(0, 1), 0.5f, Time);

	WaveHeight = sum / 2 + WaterPlaneHeight;
}

float AWaterManager::CalculateGerstnerWave(float wavelength, float amplitude, FVector2D position, FVector2D direction, float angle, float steepness, float time, float phase)
{
	float lambda = (2 * PI) / wavelength;

	FVector dir = FVector(direction.X, direction.Y, 0);
	dir = dir.RotateAngleAxis(angle * 360, FVector(0, 0, 1));

	FVector2D rotatedDirection = FVector2D(dir.X, dir.Y);

	float wavePhase = lambda * FVector2D::DotProduct(rotatedDirection, position) + (time + phase);
	float s = FMath::Sin(wavePhase);

	return amplitude * s;
}

float AWaterManager::CalculateGerstnerWaveCluster(float medianWavelength, float medianAmplitude, FVector2D position, FVector2D medianDirection, float steepness, float time)
{
	float sum = 0;

	sum += CalculateGerstnerWave(medianWavelength, medianAmplitude, position, medianDirection, 0, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.5f, medianAmplitude * 0.5f, position, medianDirection, -0.1f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 2.0f, medianAmplitude * 2.0f, position, medianDirection, 0.1f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 1.25f, medianAmplitude * 1.25f, position, medianDirection, 0.05f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.75f, medianAmplitude * 0.75f, position, medianDirection, 0.075f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 1.5f, medianAmplitude * 1.5f, position, medianDirection, -0.125f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.825f, medianAmplitude * 0.825f, position, medianDirection, 0.063f, steepness, time, 0);
	sum += CalculateGerstnerWave(medianWavelength * 0.65f, medianAmplitude * 0.65f, position, medianDirection, -0.11f, steepness, time, 0);

	return sum / 8;
}