Install OpenGL headers in Linux and compile your source files

Particularly in Ubuntu, to be accurate. I’ve spent my whole morning trying to find a way, and I’ve found a lot of nonsense. So here it is. Open Synaptic Package Manager, search for glut, or freeglut, and install the “-dev” version. As simple as that….

Yes, you are ready. Your header files (the one you installed right now, such us stdio.h, or iostream.h, etc.) can be found insinde /usr/include/GL.

You may encounter and another problem during the compile process. Assume you have the following source file as simple.c .

#include <GL/freeglut.h>

void display(void)

{
    /* clear window */
     glClear(GL_COLOR_BUFFER_BIT);

    /* draw unit square polygon */
    glBegin(GL_POLYGON);
        glVertex2f(-0.5, -0.5);
        glVertex2f(-0.5, 0.5);
        glVertex2f(0.5, 0.5);
        glVertex2f(0.5, -0.5);
    glEnd();

    /* flush GL buffers */
    glFlush();
}

void init()
{
    /* set clear color to black */

    /*  glClearColor (0.0, 0.0, 0.0, 0.0); */
    /* set fill  color to white */

    /*  glColor3f(1.0, 1.0, 1.0); */

    /* set up standard orthogonal view with clipping */
    /* box as cube of side 2 centered at origin */
    /* This is default view and these statement could be removed */

    /* glMatrixMode (GL_PROJECTION);
    glLoadIdentity ();
    glOrtho(-1.0, 1.0, -1.0, 1.0, -1.0, 1.0);  */
}

int main(int argc, char** argv)
{
    /* Initialize mode and open a window in upper left corner of screen */
    /* Window title is name of program (arg[0]) */

    /* You must call glutInit before any other OpenGL/GLUT calls */
    glutInit(&argc,argv);
    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
    glutInitWindowSize(500,500);
    glutInitWindowPosition(0,0);
    glutCreateWindow("simple");
    glutDisplayFunc(display);
    init();
    glutMainLoop();
}

if you try to ‘gcc simple.c’ errors such as ‘undefined reference’ will pop up. That is because the compiler doesn’t know where to find your library files (yeah, its a bit messy. I have no idea either why this is happening but i found the solution). To link it correctly you will have to manually tell gcc or g++ the name of you library files and this can happen by adding -l and your library file. for example

gcc simple.c -lGL -lGLU -lglut