Returns a feature containing the union of the geometries of two features.
| Usage | Returns | Feature.union(right, maxError, proj) | Feature |
| Argument | Type | Details | this: left | Element | The feature containing the geometry used as the left operand of the operation. The properties of the result will be copied from this object. |
right | Element | The feature containing the geometry used as the right operand of the operation. The properties of this object are ignored. |
maxError | ErrorMargin, default: null | The maximum amount of error tolerated when performing any necessary reprojection. |
proj | Projection, default: null | The projection in which to perform the operation. If not specified, the operation will be performed in a spherical coordinate system, and linear distances will be in meters on the sphere. |