compiling and linking programs

including header files

including header files

Most OpenGL programs and applications that only use the standard OpenGL data types, definitions, and function declarations, need only include the header file gl.h under the /opt/graphics/OpenGL/include/GL directory. Use the following syntax:

#include <GL/gl.h>

Still other header files may be needed by your program, depending on your application. For example, in order to use the OpenGL extension to X Windows (GLX) you must include glx.h, as shown below.

#include <GL/glx.h>

Instructions for including various additional header files are usually provided with the README file that accompanies a utility or function. The README also includes instructions for using or operating the utilities.

Your header file declarations at the beginning of your program should look similar to this:

#include <sys/types.h> #include <stdio.h> #include <string.h> #include <X11/X.h> #include <X11/Xlib.h> #include <X11/Xutil.h> #include <GL/gl.h>

#include <GL/glx.h>

Chapter 4

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