End of Chapter Summary

Computer graphics today encompass more than quantitative charts and graphs generated by spreadsheets. Bitmapped painting programs enable users to “paint” the screen with a mouse, pen, or other pointing device. The software stores the results in a pixel map, with each pixel having an assigned color. The more possible colors there are and the higher the resolution (pixel density) is, the more the images can approach photorealism. Object-oriented drawing programs also allow users to draw on the screen with a pointing device, with the results stored as collections of geometric objects rather than as maps of computer bits.

Bitmapped graphics and object-oriented graphics each offer advantages in particular situations; trade-offs involve editing and ease of use. Both types of graphics have applications outside the art world. Bitmapped graphics are used in high-resolution image-processing software for on-screen photo editing. Object-oriented graphics are at the heart of 3-D modeling software and computer-aided design (CAD) software used by architects, designers, and engineers. Presentation-graphics software, which may include either one or both graphics types, automates the process of creating slides, transparencies, handouts, and computer-based presentations, making it easy for nonartists to create visually attractive presentations.

With today’s computers, you aren’t limited to working with static images; they’re widely used to create and edit documents in media that change over time or in response to user interaction. For animation and digital video work, PCs mimic many of the features of expensive professional workstations at a fraction of the cost. Similarly, today’s personal computers can perform a variety of sound- and music-editing tasks that used to require expensive equipment and numerous musicians.

The interactive nature of the personal computer makes it possible to create nonlinear documents that enable users to take individual paths through information. Early nonlinear documents were called hypertext because they could contain only text. Today, we can create or explore hypermedia documents— interactive documents that mix text, graphics, sounds, and moving images with on-screen navigation buttons— on disk and on the World Wide Web.

Multimedia computer systems make a new kind of software possible—software that uses text, graphics, animation, video, music, voice, and sound effects to communicate. Interactive multimedia documents are available for desktop computers, video game machines, set-top boxes connected to televisions, and networks. Regardless of the hardware, interactive multimedia software enables the user to control the presentation rather than watch or listen passively. Only time will tell whether these new media will live up to their potential for enhancing education, training, entertainment, and cultural enrichment.