wireframe cube

[joker40]

I have this little function that draws 3d cube. I would like to use it also to draw the cube as wireframe that result I am getting is not correct. It keeps adding diagonal lines between corners of each side.

 
void myFunction(int myVar){
 
glBegin(GL_QUADS);
 
 
    glVertex3f(myVar,myVar,myVar);
    glVertex3f(-myVar,myVar,myVar);
    glVertex3f(-myVar,-myVar,myVar);
    glVertex3f(myVar,-myVar,myVar);
 
    glVertex3f(myVar,myVar,-myVar);
    glVertex3f(-myVar,myVar,-myVar);
    glVertex3f(-myVar,-myVar,-myVar);
    glVertex3f(myVar,-myVar,-myVar);
 
    glVertex3f(myVar,myVar,myVar);
    glVertex3f(myVar,-myVar,myVar);
    glVertex3f(myVar,-myVar,-myVar);
    glVertex3f(myVar,myVar,-myVar);
 
    glVertex3f(-myVar,myVar,myVar);
    glVertex3f(-myVar,-myVar,myVar);
    glVertex3f(-myVar,-myVar,-myVar);
    glVertex3f(-myVar,myVar,-myVar);
 
    glVertex3f(myVar,myVar,myVar);
    glVertex3f(-myVar,myVar,myVar);
    glVertex3f(-myVar,myVar,-myVar);
    glVertex3f(myVar,myVar,-myVar);
 
    glVertex3f(myVar,-myVar,myVar);
    glVertex3f(-myVar,-myVar,myVar);
    glVertex3f(-myVar,-myVar,-myVar);
    glVertex3f(myVar,-myVar,-myVar);
 
glEnd();
 
}

Can anyone suggest whats wrong or how to use this same function to draw cube in wireframe.

[trinitrotoluene]

I tested your code, just add glPolygonMode(GL_FRONT_AND_BACK,GL_LINE); before glBegin(). Then if you want to fill your polygon as before, call glPolygonMode(GL_FRONT_AND_BACK,GL_FILL); after glEnd();