Autodesk 12812-051462-9011 User Guide 3 - Page 1716

Overlays allow multiple scene references without the risk of creating circular dependencies. The scene XRef marked as overlay is loaded only into the master scene that references it, and is not visible in other scenes that might XRef the master file that uses the overlay. See Overlays on page 6961 for more information. WARNING If you turn off the Overlay flag for an existing XRef scene, you can cause circular XRefs to occur, that aren't detected until you or another user tries to open one of the scenes in the project. Merge Click this to merge selected XRefs into the scene as real geometry. A prompt appears so you can confirm the action. Since a merged XRef becomes part of the scene and is no longer an XRef, its name is removed from the list. Update File group Determines how and when the XRef scenes are updated. These options are applied to the selected XRefs; for example, one XRef can have automatic updating, while another can have manual updating (using the Update Now button). WARNING If you update an XRef in a scene with radiosity on page 6168, you will likely invalidate the radiosity solution. After you update the XRef, reset the radiosity solution and then recalculate it. Automatic When this check box is turned on, the selected XRef scene is automatically updated when its source scene is saved. Update Now Click this to update a selected XRef scene when you're not using Automatic (or when several XRef scenes are selected and some of them are not set to Automatic). When you click Update Now, the XRef is updated to match the latest saved version of the source scene. Display Options group These options let you specify how the selected XRefs are displayed in viewports. These options have no effect on the rendered scene. Visible Turn on or off to display or hide the selected XRefs. This affects the visibility of the XRef in the viewports only (not in renderings). Note, also, that this behavior is different from the "Enabled" check box. Turning off Visible does not remove the XRef from memory. Box Turn this on to display the selected XRefs as bounding boxes. Turn off to display the full geometry. External References (XRefs) | 6971