Graphics Programs Reference
In-Depth Information
between the part of the object close to the camera and the part farther
away increases.
In Figure 2.3, notice that when the perspective value of the object changes,
the vanishing point position changes. This change afects how the 3D object
appears in the 3D space.
Modeling
In the 3D world, the 3D object is known as the
3D model
. The 3D model
consists of one or more polygons. Understanding the anatomy of 3D models
will give you a better idea of the 3D objects imported into Photoshop from
diferent 3D programs. The 3D polygon consists of elements such as vertices,
edges, and faces, as seen in Figure 2.4.
Also, I cover working with meshes and polygons in Photoshop CS5 in
Chapter 4, where you will learn how to edit meshes in Photoshop in the
3D panel.
Vertex
The vertex is the smallest post in the model; it is a point in the 3D space that
joins two lines or two edges.
Edge
The edge is the line that separates two polygons and connects two
vertices.
Face
The face is a triangle area that consists of three points (vertices); each face is
surrounded by three lines, which are deined as edges.
Polygon
A polygon consists of two or more faces gathered in a lat area of the model;
increasing the number of polygons in the model increases the number of
faces and vertices. The more faces the polygon includes, the smoother the
polygon is when it is rendered.
Polygons with a low number of faces—known as
low polygons
—are used in
systems with low graphic resources. They are not as smooth as polygons
with a lot of faces, as you can see in old 3D games that depended on old
hardware graphic resources.
Polygon Mesh
3D models are more complicated than just lat surfaces. However, the 3D
model usually consists of many polygons arranged to form the inal shape of
the model. For instance, a ish model would consist of many polygons that
are used to form the ish shape. This arrangement of polygons is deined as
mesh of polygons
or the
polygon mesh
of the object (see Figure 2.4).
