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# getBoundingSphereCenter:radius:

Gets the center point and radius of the object’s bounding sphere.

```
- (BOOL) getBoundingSphereCenter:(SCNVector3 *) center radius:(CGFloat *) radius;
```

## Parameters

`center`

On output, the center point of the bounding sphere.

`radius`

On output, the radius of the bounding sphere.

## Return Value

<doc://com.apple.documentation/documentation/Swift/true> if the object has a nonzero volume; otherwise, <doc://com.apple.documentation/documentation/Swift/false>.

## Discussion

Scene Kit defines a bounding sphere in the local coordinate space using a center point and a radius. For example, if a node’s bounding sphere has the center point `{3, 1, 4}` and radius `2.0`, all points in the vertex data of node’s geometry (and any geometry attached to its child nodes) lie within `2.0` units of the center point.

The coordinates provided by this method are valid only if the object has a volume to be measured. If called on a geometry containing no vertex data or a node containing no geometry (and whose child nodes, if any, contain no geometry), this method returns NO, indicating that the values `*center` and `*radius` are undefined.

---

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