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CHAPTER 1 Working in Autodesk MAyA
building blocks you, as the artist, put together to create the 3D scene and animation that will
finally be rendered for the world to see. So if you can think of the objects in your scene, their
motion, and appearance as nodes, think of the Maya interface as the tools and controls you use
to connect those nodes. The relationship between these nodes is organized by the Dependency
Graph, which describes the hierarchical relationship between connected nodes. The interface
provides many ways to view the graph, and these methods are described in this chapter.
Any given workflow in Maya is much like a route on a city map. There are usually many
ways to get to your destination, and some of them make more sense than others depending on
where you’re going. In Maya, the best workflow depends on what you’re trying to achieve, and
there is typically more than one possible ideal workflow.
There are many types of nodes in Maya that serve any number of different functions. All the
nodes in Maya are considered Dependency Graph (DG) nodes. Let’s say you have a simple cube
and you subdivide it once, thus quadrupling the number of faces that make up the cube. The
information concerning how the cube has been subdivided is contained within a DG node that
is connected to the cube node.
A special type of DG node is the directed acyclic graph (DAG) node. These nodes are made
of two specific types of connected nodes: transform and shape. The arrangement of DAG nodes
consists of a hierarchy in which the shape node is a child of the transform node. Most of the
objects you work with in the Maya viewport, such as surface geometry (cubes, spheres, planes,
and so on), are DAG nodes.
To understand the difference between the transform and shape node types, think of a trans-
form node as describing where an object is located and a shape node as describing what an object
is. Transform nodes retain translation, rotation, and scale information. Often it is necessary to
freeze a node’s transforms. Freezing transformations sets the translation and rotation values to
zero and scale values to 1.0 without altering the position of the node. Doing this allows you to add
animation and mathematical expressions to zeroed values instead of complex numbers. In addi-
tion, freezing the transforms on a node that is a child of another node, forces the child to adopt the
transforms of the parent.
The simple polygon cube in Figure 1.1 consists of six flat squares attached at the edges to
form a box. Each side of the cube is subdivided twice, creating four polygons per side. That
basically describes what the object is, and the description of the object would be contained in
the shape node. This simple polygon cube may be 4.174018 centimeters above the grid, rotated
35 degrees on the x-axis, and scaled four times its original size based on the cube’s local x- and
y-axes and six times its original size in the cube’s local z-axis. That description would be in the
transform node (see Figure 1.1).
Figure 1.1
A shape node
describes the
shape of an object
and how it has
been constructed;
a transform node
describes where
the object is
located in
the scene.
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