Introduction to Blender - Blender Master Class: A Hands-on Guide to Modeling, Sculpting, Materials, and Rendering - page 11

other is updated identically. (We'll use this tech-
nique in later chapters to save time when working
on multiple copies of the same object.)
The same goes for other kinds of datablocks.
For example, in the case of materials and textures,
you can assign the same material to multiple objects
or the same texture to multiple materials, to save
time and to avoid having to create unique materials
and textures for every object. Of course, this fea-
ture also means that we have to keep track of which
object is using which datablocks and how many users
a datablock has. To see how many users a datablock
has, look next to its name in the drop-down menu
where it is selected. Datablocks with multiple users
will show how many users they have to the right of
their name (see Figure 1-14). (Click this number to
make a new, unique copy of that datablock.)
Datablocks with no users are deleted when you
quit Blender. To keep a datablock that has no users,
such as a material you might want to reuse or an ear-
lier version of a mesh datablock, protect it by click-
ing the F icon next to the datablock's name (see
Figure 1-14). This creates a “fake” user so that the
datablock will be saved along with your file.

hair and paint vertex groups for controlling fur.
Then, in Chapter 11, we'll use Texture Paint mode
to paint textures on our models.

Saving and Loading
Saving and loading in Blender works much the same
way that it does in any application. Use File 4 Save
( ctrl -S) to save and File 4 Open ( ctrl -O) to open
a file.
Blender saves files in a unique .blend format. By
default, external files, such as images loaded into
Blender, are not saved along with the .blend file but
are referenced relative to the file. Thus, to open a
.blend file on another computer, you need to copy
over the .blend file plus all the other files it refer-
ences and re-create the same directory structure
before opening the .blend file. Alternatively, you can
“pack” your .blend file, which saves external data
such as images within the .blend file, so that you can
then open up the .blend file on any machine and
have all the data it needs.

Appending and Linking
Blender lacks the standard copy-and-paste function-
ality for objects or other kinds of datablocks that you
might expect from using more conventional applica-
tions. To copy an object, you can either duplicate
it or simply reference the same datablock using an
existing object. But what if you want to bring some-
thing in from an external .blend file?
That's where the Append and Link features
come in. Appending and linking let you bring data-
blocks from one .blend file into another. Append
(File 4 Append) brings the datablock wholly into
the current .blend file as an independent copy of the
original. Linking (File 4 Link) references the original
datablock in the other file. Linked datablocks can-
not be edited in the . blend file they are linked into;
rather, they must be edited in the original file.
Appending is useful for quickly bringing an
existing resource into your .blend file so that you
can use and edit it. Linking is useful for combin-
ing multiple elements in larger projects when, for
example, different people are editing various parts
independently. By linking all the elements of a proj-
ect into one scene, people can work on parts inde-
pendently in separate .blend files, while keeping the
final assembly of multiple linked objects up-to-date.
(If you link a datablock and wish to edit it locally,
make it into a local datablock using the Make Local
operator ( L ).)

Naming Datablocks
To rename a datablock, click its name. When
naming datablocks, it's good practice to give them
descriptive names to make it easier to pick a par-
ticular datablock from a list. Renaming your data-
blocks with descriptive words, such as Wood , Red
Paint , Skin , and so on, will make your scene easier
to navigate and understand later on.

Modes
Blender has different modes for editing the differ-
ent aspects of an object's data. The default is Object
mode, which lets you add and delete objects and
also move, scale, and rotate them. Other modes
let you edit mesh data and particle systems, sculpt
on meshes, paint textures, and adjust vertex group
weights.
Blender's two most important modes are Object
and Edit mode. To switch between them, use the
hotkey tab . To access other modes, click the Modes
drop-down menu in the header of the 3D Viewport
(see Figure 1-5) and select the mode you want.
In Chapters 4 and 5, we'll use Edit mode exten-
sively for modeling, and in Chapter 6, we'll use Sculpt
mode. Then in Chapter 8, we'll use Particle mode
and Weight Paint mode to create and comb particle