Graphics Reference
In-Depth Information
Chapter 1
This chapter introduces computer graphics quite broadly and from several per-
spectives: its applications, the various fields that are involved in the study of
graphics, some of the tools that make the images produced by graphics so effec-
tive, some numbers to help you understand the scales at which computer graphics
works, and the elementary ideas required to write your first graphics program.
We'll discuss many of these topics in more detail elsewhere in the topic.
Computer graphics
is the science and art of communicating visually via a com-
puter's display and its interaction devices. The visual aspect of the communica-
tion is usually in the computer-to-human direction, with the human-to-computer
direction being mediated by devices like the mouse, keyboard, joystick, game
controller, or touch-sensitive overlay. However, even this is beginning to change:
Visual data is starting to flow
back
to the computer, with new interfaces being
based on computer vision algorithms applied to video or depth-camera input. But
for the computer-to-user direction, the ultimate consumers of the communica-
tions are human, and thus the ways that humans perceive imagery are critical in
the design of graphics
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programs—features that humans ignore need not be pre-
sented (nor computed!). Computer graphics is a cross-disciplinary field in which
physics, mathematics, human perception, human-computer interaction, engineer-
ing, graphic design, and art all play important roles. We use physics to model
light and to perform simulations for animation. We use mathematics to describe
shape. Human perceptual abilities determine our allocation of resources—we
don't want to spend time rendering things that will not be noticed. We use engi-
neering in optimizing the allocation of bandwidth, memory, and processor time.
Graphic design and art combine with human-computer interaction to make the
computer-to-human direction of communication most effective. In this chapter,
1. Throughout this topic, when we use the term “graphics” we mean “computer graphics.”
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