If you already know the distance and the rotation, you can do something like this:

This function will return the final location for the mesh. Also, you should set the mesh’s rotation to the same rotation used in this function.

If you already know the distance and the rotation, you can do something like this:

This function will return the final location for the mesh. Also, you should set the mesh’s rotation to the same rotation used in this function.

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How can I rotate a mesh around an arbitrary point in space?

For example a moon rotating around a planet.

Thanks

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Perfect. Thanks!!

Would be possible to create a blueprint function that generates an ellipse movement around an arbitrary point in space. A function that we could input the center point position + the two ellipse focus points positions (that will define the ellipse shape). Is there a way to do it?

Here is my solution to it. It will rotate the object around the given Pivot using the objects own rotation. E.g. A delta rotation around Z will rotate around the objects Z axis. Optionally you can retain the rotation of the object itself.

You can write this as a function, for sure.

```
UFUNCTION(BlueprintPure)
static void RotateAroundPivot(const FTransform& Original, const FVector PivotLocation, const FRotator DeltaRotation, bool bRetainOrientation, FTransform& New)
{
FTransform PivotTransform = FTransform(Original.GetRotation(), PivotLocation);
FTransform DeltaPivotToOriginal = Original * PivotTransform.Inverse();
New = FTransform(DeltaRotation.GetInverse() * (float)bRetainOrientation, FVector(0,0,0)) * DeltaPivotToOriginal * FTransform(DeltaRotation, FVector(0,0,0)) * PivotTransform;
}
```

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This works regardless of the initial orientation as it doesn’t require the forward vector and has solved my issue of rotating a parent actor around a child actor. I’ve been struggling with this for hours. Thank you so much!

I found a good way to do this was to do something like this:

```
FVector pointLocation = ...
FVector thingYouRotatePosition = ...
float amountYouWantToRotate = ... //(0-2pi)
// make a Quaternion with an upward axis (rotating around the upwards axis)
FQuat rotation = FQuat(FVector::UpVector, amountYouWantToRotate);
// get the offset of you the thing you are rotating, from the point
FVector offset = pointLocation - thingYouRotatePosition;
// rotate it and add that to the point location
FVector newRotation = rotation.RotateVector(offset) + pointLocation;
```

Quaternions are really handy once you learn how to use them. Though most of the explanations I’ve seen seem a little complicated.

How they work is that you give them a vector that tells it what to rotate around, and then you tell it how much to rotate around that ‘axis’. So if you give it a vector that points straight up, it’ll rotate around that like I did above.

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