Manual/Library and Data System

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Contents [hide] 1 Basic Information 2 Outliner and OOPS Schematic 3 Multiple Users 4 Fake User 5 Copying and Linking Objects Between Scenes 6 Appending or Linking Across Files 7 Proxy Objects

Basic Information

Each Blender file contains a database. This database contains all scenes, objects, meshes, textures, etc. that are in the file. A file can contain multiple scenes and each scene can contain multiple objects. Objects can contain multiple materials which can contain many textures. It is also possible to create links between different objects.

To access the database, press Shift F4 and the window will change to an Datablock browser window, which lists the Objects in your blend file. To go up a level, click the breadcrumbs (..) and then you will see the overall structure of a file: Action, Armature, Brush, Camera, Curve, Group, ... and so on (including Objects).

LMB Selecting any datablock type, Mesh, for example, will give you a listing of the Meshes used in the file, along with how many users there are for that class. For example, if you had a car mesh, and used that car mesh for six cars in a parking lot scene, the Mesh listing would show the Car and then the number 6.

RMB Selecting certain kinds of datablocks (Materials, Images, Textures...) and pressing F will assign a Fake user to those datablocks. With a fake user in place, Blender will keep those datablocks in the file, even if they have no 'real' users. Datablocks without a user, real or fake, are not saved in the blend file. Pressing F again toggles the Fake-user assignment. Performing this action is the same as clicking the F button next to Material names, Image names, etc.

Outliner and OOPS Schematic

You can easily inspect the contents of your file by using the Outliner window. This window displays the Blender data system. (Fully documented here.) This window offers two views of the database. The Outline view allows you to do simple operations on the objects. These operations include selecting, renaming, deleting and linking. The OOPS (Object-Oriented Programming System) Schematic view allows you to easily see how datablocks are linked. You can filter the view by using buttons found in the header.

Multiple Users

Many datablocks can be shared among other datablocks; re-use is encouraged. For example, suppose you have a material for one object, named "Glossy". You can select a second object, for example, one that does not have a material yet. Instead of clicking ADD NEW for the material, click the little up-down arrow next to the ADD NEW, which brings up a list of existing materials. Select "Glossy". Now, these two objects share the same Material. You will notice a "2" next to the name of the material, indicating that there are two users (the two objects) for this material. Other common examples include:

Sharing textures among materials

Sharing meshes between objects ("clones")

Sharing IPO curves between objects, for example to make all the lights dim together.

Fake User

Blender removes all datablocks that have not been linked to anything when you open the file. Because of this, sometimes you may find it useful to link unlinked datablocks to a "fake user". You can do this by hitting the F button next to the name of the datablock.

Copying and Linking Objects Between Scenes

Sometimes you may want to link or copy objects between scenes. This is possible by first selecting objects you want to link or copy and then using the "Make Links" and "Make Single User" items found in Object menu in the 3D viewport header. Use "Make Links" to make links between scenes. To make a plain copy, you first make a link and then use "Make Single User" to make a stand-alone copy of the object in your current scene. Further information on working with Scenes can be found here.

Appending or Linking Across Files

The content of one blend file is easily accessed and put into your current file by using the File->Append function (accessed at any time by Shift F1. To find out more about how to copy or link objects across blend files, click here.

Proxy Objects

Proxy Objects allow you to make (parts of) Linked data local. For example, this allows an animator to make a local 'copy' of the handler bones of a character, without having the actual rig duplicated. This is especially useful for character animation setups, where you want the entire character to be loaded from an external library, but still permit the animator to work with Poses and Actions. Another example: you can have a modeler working on the shape (mesh) of a car and another painter work on the materials for that car. The painter cannot alter the shape of the car, but can start working with color schemes for the car. Updates made to the shape of the car are applied automatically to the painter's proxy.

See also this for more useful information about the database system.

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