圆周运动

 贝塞尔曲线路径运动

 蓝图函数库创建贝塞尔曲线点

// Fill out your copyright notice in the Description page of Project Settings.

#pragma once

#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "MyBlueprintFunctionLibrary.generated.h"

/**
 * 
 */
UCLASS()
class CARTEST_API UMyBlueprintFunctionLibrary : public UBlueprintFunctionLibrary
{
	GENERATED_BODY()
	
public:
	UFUNCTION(BlueprintCallable, Category = "BezierCurve")
	static TArray<FVector> GenerateBezierCurvePoints(const FVector& P0, const FVector& P1, const FVector& P2, int32 NumPoints);
	
	
};

// Fill out your copyright notice in the Description page of Project Settings.


#include "MyBlueprintFunctionLibrary.h"


TArray<FVector> UMyBlueprintFunctionLibrary::GenerateBezierCurvePoints(const FVector& P0, const FVector& P1,
	const FVector& P2, int32 NumPoints)
{
	TArray<FVector> CurvePoints;

	// 确保 NumPoints 大于 1，否则没有足够的点来生成曲线
	if (NumPoints < 2) 
	{
		UE_LOG(LogTemp, Warning, TEXT("NumPoints 必须大于 1"));
		return CurvePoints;
	}

	// 创建临时点数组用于曲线生成
	TArray<FVector> TempPoints;
	for (int32 i = 0; i < NumPoints; i++)
	{
		float t = static_cast<float>(i) / (NumPoints - 1);
		FVector Point = FMath::Lerp(FMath::Lerp(P0, P1, t), FMath::Lerp(P1, P2, t), t);
		TempPoints.Add(Point);
	}

	// 计算曲线总长度和各段长度
	float TotalLength = 0.0f;
	TArray<float> SegmentLengths;
	for (int32 i = 1; i < TempPoints.Num(); i++)
	{
		float SegmentLength = FVector::Dist(TempPoints[i - 1], TempPoints[i]);
		SegmentLengths.Add(SegmentLength);
		TotalLength += SegmentLength;
	}

	// 防止 TotalLength 为 0
	if (TotalLength <= KINDA_SMALL_NUMBER)
	{
		UE_LOG(LogTemp, Warning, TEXT("曲线总长度为 0"));
		CurvePoints.Add(P0); // 添加起点
		CurvePoints.Add(P2); // 添加终点
		return CurvePoints;
	}

	// 计算等距点
	CurvePoints.Add(P0); // 起点
	float SegmentTarget = TotalLength / (NumPoints - 1);
	float DistanceAccumulated = 0.0f;

	for (int32 i = 1; i < TempPoints.Num(); i++)
	{
		DistanceAccumulated += SegmentLengths[i - 1];
		while (DistanceAccumulated >= SegmentTarget)
		{
			float LerpAlpha = (SegmentTarget - (DistanceAccumulated - SegmentLengths[i - 1])) / SegmentLengths[i - 1];
			FVector Point = FMath::Lerp(TempPoints[i - 1], TempPoints[i], LerpAlpha);
			CurvePoints.Add(Point);
			DistanceAccumulated -= SegmentTarget;
		}
	}

	CurvePoints.Add(P2); // 终点
	return CurvePoints;
}