Autodesk 663B1-05A111-1001 User Guide - Page 219

12 | Basics Menus Reference > File > Create Reference Maya uses the display layer name to determine how the referenced layer is added to the current scene. If a display layer name already exists in the parent scene, any objects assigned to an identically-named display layer in a child scene are added to the original parent display layer when they are referenced. If a child scene contains a display layer that does not exist in the parent scene, the layer from the child scene appears in the parent scene when the child scene is referenced. If these child scenes are later removed from the parent scene, their associated layers are removed as well. Shared layers are automatically placed in the default namespace. Shading Networks If you reference a file into your current scene with shared shading networks enabled, the shading networks from the referenced scene are combined with those in the current scene (including those of any references). This avoids creating duplicate shading networks when you want the same ones used throughout your scene, including the reference. Shading networks can only be shared if the shading networks are identical. Maya considers two shading networks to be identical only if all the nodes included in it have both the same name and type while traveling upstream from the shading group. While the name and type of each node in the shading network must be identical in order for the shading network to be shared, the actual values in each node are not considered. So, a node in a child scene with one value (for example, blue) is considered identical to a node in the parent scene with a different value (for example, red) as long as its name and type match. However, certain shading networks cannot be shared. They are: • networks that include DAG objects (such as those that include the place3dTexture node) • networks with animation applied to a node • networks with an expression applied to a node If any of these items appear in the shading network, the network is not shared when the file is referenced with shared shading networks enabled. Any items that exist downstream of the shading network are also not shared. The only items shared are those items upstream of the shading network. Render Layers When the reference is created, the render layers associated with the child scene are integrated into the parent scene. You can choose to use the render layer name or number to determine which render layers are merged. If a render layer name or ID already exists in the parent scene, any objects assigned to a render layer with the same name or ID in a child scene are added to the referencing scene's render layer when they are referenced. Basics 219