代码:

float Len = FMath::Sqrt(100 * 100 + 100 * 100);
FVector Loc = FVector(100.f, 100.f, 0.f) + FRotator(0.f, 45.f, 0.f).Vector() * Len;

结果:

Loc = {X=200.f, Y=200.f, Z=0.f}

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例子2:

float Len = FMath::Sqrt(100 * 100 + 100 * 100);
FVector Loc1 = FVector(0.f, 0.f, 0.f) + FRotator(0.f, 45.f, 0.f).Vector() * Len;
FVector Loc2 = FVector(0.f, 0.f, 0.f) + FRotator(0.f, 135.f, 0.f).Vector() * Len;
FVector Loc3 = FVector(0.f, 0.f, 0.f) + FRotator(0.f, 225.f, 0.f).Vector() * Len;
FVector Loc4 = FVector(0.f, 0.f, 0.f) + FRotator(0.f, 315.f, 0.f).Vector() * Len;

结果:

Loc1 = {X=100.f, Y=100.f, Z=0.f}
Loc2 = {X=-100.f, Y=100.f, Z=0.f}
Loc3 = {X=-100.f, Y=-100.f, Z=0.f}
Loc4 = {X=100.f, Y=-100.f, Z=0.f}