SGI Windows NT Toolbox
OpenGL Documentation
  • Current OpenGL Specifications

  • Way cool, way fast OpenGL rendering techniques 12/97

  • OpenGL and Windows NT, Developer News, 9/98
    This is the first of a two-part article. Issue covered include OpenGL rendering, OpenGL in standard Windows®, and the integration of OpenGL with the Microsoft® Foundation Classes.

  • www.opengl.org is THE single most content-rich source on the web
     
    

    Document Abstracts/Overviews:


    • OpenGL Specification:
      The OpenGL Graphics System: A Specification

      Introduction:

      This document describes the OpenGL graphics system: what it is, how it acts, and what is required to implement it. We assume that the reader has at least a rudimentary understanding of computer graphics. This means familiarity with the essentials of computer graphics algorithms as well as familiarity with basic graphics hardware and associated terms. . . .

      1.2     What is the OpenGL Graphics System?

      OpenGL (for "Open Graphics Library") is a software interface to graphics hardware. The interface consists of a set of several hundred procedures and functions that allow a programmer to specify the objects and operations involved in producing high-quality graphical images, specifically color images of three-dimensional objects.

      Most of OpenGL requires that the graphics hardware contain a framebuffer. Many OpenGL calls pertain to drawing objects such as points, lines, polygons, and bitmaps, but the way that some of this drawing occurs (such as when antialiasing or texturing is enabled) relies on the existence of a framebuffer. Further, some of OpenGL is specifically concerned with framebuffer manipulation. . . .

      1.5.     Our View

      We view OpenGL as a state machine that controls a set of specific drawing operations. This model should engender a specification that satisfies the needs of both programmers and implementors. It does not, however, necessarily provide a model for implementation. An implementation must produce results conforming to those produced by the specified methods, but there may be ways to carry out a particular computation that are more efficient than the one specified.


    • GLU Specification:
      The OpenGL(TM) Graphics System Utility Library

      Overview:

      The GL Utilities (GLU) library is a set of routines designed to complement the OpenGL graphics system by providing support for mipmapping, matrix manip-ulation, polygon tessellation, quadrics, NURBS, and error handling. Mipmapping routines include image scaling and automatic mipmap generation. A variety of matrix manipulation functions build projection and viewing matrices, or project vertices from one coordinate system to another. Polygon tessellation routines convert concave polygons into triangles for easy rendering. Quadrics support renders a few basic quadrics such as spheres and cones. NURBS code maps complicated NURBS curves and trimmed surfaces into simpler OpenGL evaluators. Lastly, an error lookup routine translates OpenGL and GLU error codes into strings. GLU library routines may call OpenGL library routines. Thus, an OpenGL context should be made current before calling any GLU functions. Otherwise an OpenGL error may occur.

      All GLU routines, except for the initialization routines listed in Section 2, may be called during display list creation. This will cause any OpenGLcommands that are issued as a result of the call to be stored in the display list. The result of calling the intialization routines after glNewList is undefined.


    • GLX Specification:
      OpenGL Graphics with the X Window System

      Overview:

      This document describes GLX, the OpenGL extension to the X Window System. It refers to concepts discussed in the OpenGL specification, and may be viewed as an X specific appendix to that document. Parts of the document assume some acquaintance with both the OpenGL and X.

      In the X Window System, OpenGL rendering is made available as an extension to X in the formal X sense: connection and authentication are accomplished with the normal X mechanisms. As with other X extensions, there is a defined network protocol for the OpenGL rendering commands encapsulated within the X byte stream.

      Since performance is critical in 3D rendering, there is a way for OpenGL rendering to bypass the data encoding step, the data copying, and interpretation of that data by the X server. This direct rendering is possible only when a process has direct access to the graphics pipeline. Allowing for parallel rendering has affected the design of the GLX interface. This has resulted in an added burden on the client to explicitly prevent parallel execution when that is inappropriate.

      X and the OpenGL have different conventions for naming entry points and macros. The GLX extension adopts those of the OpenGL.





Web Accessible Files of the documents/OpenGL directory:

This is an automatically derived categorization of files of this directory. Only files which can be displayed or heard in some manner are included. Files may be immediately accessed by clicking the corresponding link. Zip Archives (if present) contain all files in the specified sub- directory/tree.

Documentation

Images

Subdirectories

Zip Archives


Copyright © 1995-98, Silicon Graphics, Inc.