Datasheet

4 Chapter 1: Working in 3D
option without changing the scene in any way, but it is important to note that both cam-
era and light perspectives are tied to actual objects in 3D space. us, if you move these
views, you will actually be moving (or rotating) objects and changing the makeup of the
scene. Movement in camera and light perspectives can be reversed with the Undo com-
mand, but movement in the generic perspective view cannot be undone.
A common analogy is that if an Adobe Photoshop (or other 2D graphic) image is like a
painting, a 3D document is like a sculpture. Two-dimensional art forms (digital and ana-
log) use space, form, and color to create the nished image. Depth and dimension are cre-
ated through color variation for simulation of light and shadow. ree-dimensional art
adds volume to the mix, which oers more-concrete simulation of real light and shadow.
Because 3D provides added levels of realism, you need to consider additional parts of the
creative process in order to create compelling 3D art.
Exploring a 3D Scene
e next things to consider when beginning to work in 3D are the individual pieces of
a 3D scene and the steps in the creative process that will result in a nished project (a
model, still image, animation, and so forth). is space is lled with points, edges, and
polygons that create the objects. Materials and textures control the appearance of objects.
Lights add shading and highlights to the scene. e camera provides the vantage point for
the nished scene. Lets look at each of these in more depth.
Points, Edges, and Polygons
At the heart of any model that you will create are three basic elements: points (also called
vertices), edges, and polygons. Points represent a single location in space. e initial
impulse is oen to think of these as being analogous to pixels in a raster image, but this is
not the case. Because a vertex represents a single point in space, it is innitesimally small
and therefore does not appear in a nished 3D render. e fact that the vertex is the basic
building block of the 3D creative process means that it is visible only when several are
combined to create edges and polygons.
Edges make up the next level in the 3D food chain. When two points are joined
together, an edge is created. is edge now exists in one dimension and is still invisible
to the nished rendering. Once again, this should not be confused with a line in a 2D
image le. For both edges and points, it is better to consider a vector illustration without
any line weight assigned. Individual points and lines may appear on the page, but they
will not print unless some thickness is attached to these elements. To see these elements,
you must have a combination of at least three of them (points and edges), which creates a
polygon.
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