Modeling and Rendering
To create images such as that shown in
Figure 1
, you typically engage in at least two distinguishable main tasks: modeling and rendering.
Modeling
is the process of creating a representation of real or abstract objects, and
rendering
is the process of creating an image (on the screen or some other medium) of a model. QuickDraw 3D subdivides each of these tasks into a number of subtasks.
In QuickDraw 3D,
modeling
involves
-
creating, configuring, and positioning basic
geometric objects
and
groups
of geometric objects. QuickDraw 3D defines many basic types of geometric objects and a large number of ways to
transform
such objects.
-
assigning sets of
attributes
(such as diffuse and specular colors) to objects and
parts
of
objects.
-
applying
textures
to surfaces of objects.
-
configuring a model's
lights
and
shading.
QuickDraw 3D supplies four types of lights (ambient light, directional lights, spot lights, and point lights) and several types of shaders.
In QuickDraw 3D,
rendering
involves
-
specifying a
camera
position and type. A camera type is defined by a method of projecting the model onto a flat surface, called the view plane. QuickDraw 3D provides two types of cameras that use perspective projection (the aspect ratio and view plane cameras) and one type of camera that uses parallel projection (the orthographic camera).
-
specifying a
renderer
or method of rendering. QuickDraw 3D provides a wireframe and an interactive renderer. Renderers support different
styles
of rendering (for example, points, edges, or filled shapes).
-
creating a
view
(a collection of a group of lights, a camera, and a renderer and its styles) and rendering the model using the view to create an
image.
© 1997 Apple Computer, Inc.
