Graphics - Commodore VIC-20 User Manual

CHAPTER
Graphics
In
this book, "graphics" means the display of pictures, rather than text,
data, or programs, on the screen. The "picture" could be a face, an architec-
tural drawing, a geometric shape, or simply an arrangement of text
characters.
The VIC 20 has extensive graphics capabilities. Some of these, such as
the built-in graphics characters and the VIC's ability to display text and
pictures in color, have been mentioned in the preceding chapters. We will
cover these features in more detail in this chapter and describe the VIC's
other graphics features, such as its ability to use characters you design. As
these features are introduced, we will show you programming techniques for
using them to produce colorful and animated displays.
Video Interface Chip
The Video Interface Chip (VIC chip) is a complex integrated circuit
that generates the picture and sound that the VIC produces on your televi-
sion. It is the origin of the VIC's name.
The first job of the VIC chip is to act as a video interface. It translates
computer signals into television signals that produce a picture on the screen.
The VIC chip also generates the sounds that you hear through the
television speaker. Chapter 7 examines the sound portion of the chip.
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