Opengl doesnt work

[youngcoder13]

hello, I have this code

/*
* simple.c
* This program draws a white rectangle on a black background.
*/


/* E. Angel, Interactive Computer Graphics */

/* A Top-Down Approach with OpenGL, Third Edition */

/* Addison-Wesley Longman, 2003 */



#ifdef __APPLE__
#include <GLUT/glut.h>
#else
#include <GL/glut.h> /* glut.h includes gl.h and glu.h*/
#endif


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();

}

and it does not work on my mac using xcode. It has 13 erros saying things like "_glBegin", referenced from:
display() in File.o and at the end the last error is linker command failed with exit code 1 (use -v to see invocation).

Please help me, thank you!

[Computergeek01]

The function "glBegin()" is a core part of the OpenGL library, did you remember to link to "Opengl32.lib" or "libopengl32.a"?

EDIT: Also copy paste the errors, it doesn't do anyone any good for us to guess at what you're talking about.

[youngcoder13]

I am using xcode on mac, I hate mac! I am going to get a windows as soon as possible.

EDIT: And why is this error occuring? linker command failed with exit code 1 (use -v to see invocation

[ne555]

Because you need to link the libraries
¿which compiler are you using? for gcc it would be -l{GL,glut}

[Moschops]

The bigger picture here is that you're trying to code in C++ without an understanding of what the tools do. You need to go back and learn what a compiler is and what it does to turn a single text file into a single binary object, and what a linker is and ow it turns many binary objects into a single library or executable.

If you knew the basics, you would ave been able to answer this question yourself. Understanding the basics will help you enormously in the future.