Skip to main content
main-content

Über dieses Buch

The Programmer's Hierarchical Interactive Graphics System (PHIGS) is a computer-graphics standard defining an interface between an application program and a computer-graphics system. PHIGS has been actively under development since 1980. Much of this development has been performed by Technical Committee X3H3 under the American National Standard Institute (ANSI) procedures. PHIGS is also an international standard sponsored by the United States and developed by the international computer-graphics committee, ISO TC97/SC21/WG2. In addition, PHIGS has been selected as the graphics extension to the X-window standard and as part of the Intel i860 P.A.X. standard. The PHIGS standard has received wide acceptance throughout the computer­ graphics industry. PHIGS libraries are available on most of the high­ performance three-dimensional graphics platforms. These include IBM, DEC, HP, Sun, Alliant, Stardent, and Silicon Graphics. Despite this acceptance, there are few texts that provide the software engineer with an overview of the standard. The only currently available PHIGS references are in the form of the ANSI functional description, technical papers, and device-specific PHIGS to the novice PHIGS programmer.

Inhaltsverzeichnis

Frontmatter

Introduction

Abstract
The Programmer’s Hierarchical Interactive Graphics System (PHIGS) is a computer-graphics standard defining an interface between an application program and a computer-graphics system . PRIGS has been actively under development since 1980. Much of this development has been performed by Technical Committee X3H3 under the American National Standard Institute (ANSI) procedures. PHIGS is also an international standard sponsored by the United States and developed by the international computer-graphics committee, ISO TC97/SC211WG2. In addition, PHIGS has been selected as the graphics extension to the X-window standard and as part of the Intel i860 P.A.X. standard
William A. Gaman, William A. Giovinazzo

1. Drawing with PHIGS

Abstract
This chapter provides the reader with some basic concepts in PHIGS. On completion of this chapter the reader will be able to create a graphic object and change its appearance.
William A. Gaman, William A. Giovinazzo

2. Coordinate Systems and Transformations

Abstract
PHIGS is useful for displaying geometric data from a variety of sources because it allows the user to define an object in whatever coordinate space is most convenient. An object may be defined in angstrom units, inches, meters, light years, or any system that suits the application. The units of measure chosen are defined within a modeling coordinate system using the applicable measurements. PHIGS transforms the objects defined within the modeling coordinate system to physical locations on the graphics output device. These locations are within the device coordinate system. The process of conversion between the user-defined modeling coordinate system to the device coordinate system is known as the transformation pipeline.
William A. Gaman, William A. Giovinazzo

3. More on Structures

Abstract
This chapter will introduce some of the more dynamic capabilities provided by the hierarchical nature of PHIGS. On completion of this chapter the reader will be able to create multiple structures linked in a hierarchical manner. The reader will also be able to dynamically modify these structures in order to simulate motion.
William A. Gaman, William A. Giovinazzo

4. The Wonderful World of Color

Abstract
This chapter elaborates on the use of color attributes. On completion of this chapter, the reader will be able to build color tables and create output primitives using different color models. As shown in Figure 4.1, there are three different types of color. Color representation and color approximation representation are both subtypes of indexed color. Both methods of indexed color are workstation dependent. Direct color is a nonindexed method of specifying color that is workstation-independent.
William A. Gaman, William A. Giovinazzo

5. Shading and Lighting

Abstract
This chapter introduces the basic concepts necessary for the creation of graphical objects with surface attributes and light sources that affect the appearance of the object’s surface. Upon completion of this chapter, the reader will be able to create 3-D graphic objects that appear smooth-shaded. The surface color of a smooth-shaded object is interpolated across the surface. In addition to creating a smooth-shaded object the reader will be able to specify various light sources to produce visual effects which can be used to simulate the real world.
William A. Gaman, William A. Giovinazzo

6. PHIGS Input Devices

Abstract
All of the example images presented up to this point have been modified via program control. PHIGS, however, provides the application programmer with a variety of logical input device types that allow the user to interact with the display. A logical input device is an abstraction of one or more physical devices that provides input to the PHIGS program. A mouse, for example, is one physical device. As we shall see in Section 2.2, however, the buttons on the mouse are seen as separate, independent input devices. Each mouse button is said to be a logical input device. In this chapter we discuss the different types of devices allowed by PHIGS. On completion of this chapter, the reader will be able to initialize and read a logical input device.
William A. Gaman, William A. Giovinazzo

Backmatter

Weitere Informationen