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[edit] Datablocks

The base unit for any blender project is the datablock. The datablocks and the ways those are linked together are all there is to it, may it be a simple still image of a sphere floating over a plane or a full featured film. These datablocks can reside within as many .blend files as needed for the good organization of the project.

[edit] Scene Datablock

Each Scene datablock contains a scene. This type of datablock is the parent of all the others.

[edit] Object Datablock

Each Object datablock has the properties of Location, Rotation and Scale, and is the “meeting place” for other datablocks that define the other properties of that object when they are linked to it. They can determine its nature: mesh, curve, camera, lamp or armature datablocks are a few examples of such datablocks. Others will define the material, the texture, the animation… for that object.

[edit] ObData Datablocks

These datablocks are always connected to Object datablocks in a way or another.

[edit] Curve Datablock

Curve datablocks may contain NURBS curves, circles or surfaces, Bézier curves or circles, or Text objects. It may also be linked to a Material datablock.

[edit] Camera Datablock

Camera datablocks contain a camera.

[edit] Lattice Datablock

Lattice datablocks contain a lattice.

[edit] Lamp Datablock

Lamp datablocks contain a lamp.

[edit] Metaball Datablock

Metaball datablocks contain a metaball.

[edit] Mesh Datablock

Mesh datablocks contain a mesh. These datablocks may contain link to one or more Material datablocks.

[edit] Material Datablock

Material datablocks contain a material. They may contain links to Texture datablocks.

Note that Material datablocks can be linked to Object datablocks instead if desired. You can set this in the User Preferences window, below Edit Methods.

[edit] Texture Datablock

Texture datablocks contain a texture (procedural, image…).

[edit] Copying and Linking Datablocks

It is possible to copy or link any type of datablock.

[edit] Copying and Linking Scene Datablock

To copy a Scene datablock, use Scene list found in the header of User Preferences window. The list is to the right of the menus and window workspace list. Select ADD NEW to make a copy of the current scene. Select Full Copy from the list that opened to make a copy. The current scene will be fully copied to the new scene.

Instead of copying everything, you can link datablocks by selecting Link Objects, to use the same Object datablocks linked into the two scenes, or Link ObData, to create separated objetcs sharing the same ObData datablocks (meshes, curves, materials, etc.). Note that if you select Link Objects, in fact you copy nearly nothing, as Object datablocks are parent of all ObData datablocks: nearly all modifications (object location, mesh geometry, …) in a scene will be reflected in the other ones linked this way as well. As for Link ObData, it creates a “real” copy of the objects, but not of their child datalocks: the locations, scales and rotations of the objects will be specific to a scene, but neither their forms nor their materials, textures, …, will be (as defined by ObData datablocks).

[edit] Copying and Linking Object Datablocks

Full copy

⇧ ShiftD is used to make normal copy of the selected objects.

The object and some of it’s child datablocks will really be duplicated, the other children are just linked; you can define the attributes to be duplicated in User Preferences → Edit Methods, button group Duplicate with object:.

Linked copy

AltD makes a linked copy.

All datablocks but the object one are linked.

[edit] Copying and Linking other Datablocks

When an ObData datablock is used (linked) by more than one object, a small button with its number of linked objects (users) shows up next to its name, in its settings window (Editing context for meshes, curves, cameras, …, Shading context, Material sub-context for materials, etc.). If you click on it, you create a copy of this datablock for the current object.