How do I change the viewing angle in OpenGL? - c++

Question

I need to create a 3d cube, and so far I've created all the vertices but when I run the program I can only see the cube (or what I hope is a cube, I can't tell) from one face, so it looks like a square. I want to know how to view my cube from above, so I can check whether or not it actually looks the way I want it to.
I created the 24 vertices using glVertex3f but like I said I can't tell if it is a cube or not because I cannot look at it from an angle other than the default.
I tried downloading GLM but I am very confused on how, if at all, to use that to change the viewing perspective.
glEnable(GL_DEPTH_TEST);
// Loop until the user closes the window
while (!glfwWindowShouldClose(window))
{
// Render here
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glBegin(GL_QUADS);
glColor3f(0.0f, 1.0f, 0.0f);
glVertex3f(0.5f, 0.5f, 0.5f);
glVertex3f(-0.5f, 0.5f, 0.5f);
glVertex3f(-0.5f, -0.5f, 0.5f);
glVertex3f(0.5f, -0.5f, 0.5f);
... // Repeating drawing the vertices for each vertex of the cube
glEnd();
// Swap front and back buffers
glfwSwapBuffers(window);
// Poll for and process events
glfwPollEvents();
}
No error messages but I cant tell if its a cube or not.

Answer 1

// Render here
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
// need the window width & height to compute aspect ratio
int width, height;
glfwGetWindowSize(window, &width, &height);
// set up the camera projection (if you haven't done this in init)
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0f, float(width) / height, 0.1f, 100.0f);
// set camera position & orientation
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(1, 1, -3, //< eye position
0, 0, 0, //< aim position
0, 1, 0); //< up direction
// now draw stuff
glBegin(GL_QUADS);
glEnd();