Question

Trying to make a sphere. But it so doesn’t look like 3D, in fact it looks like a flat 2D picture. What am I missing here?

Thankyou

std::vector<GLfloat> ballVerts;

for(int i = 0; i <= 40; i++)
{
    double lat0 = M_PI * (-0.5 + (double) (i - 1) / 40);
    double z0  = sin(lat0);
    double zr0 =  cos(lat0);

    double lat1 = M_PI * (-0.5 + (double) i / 40);
    double z1 = sin(lat1);
    double zr1 = cos(lat1);

    for(int j = 0; j <= 40; j++)
    {
        double lng = 2 * M_PI * (double) (j - 1) / 40;
        double x = cos(lng);
        double y = sin(lng);

        //  normals
        glNormal3f(x * zr0, y * zr0, z0);

        ballVerts.push_back(x * zr0); //X
        ballVerts.push_back(y * zr0); //Y
        ballVerts.push_back(z0);      //Z

        ballVerts.push_back(0.0f); 
        ballVerts.push_back(1.0f); 
        ballVerts.push_back(0.0f); 
        ballVerts.push_back(1.0f); //R,G,B,A

        //  normals
        glNormal3f(x * zr1, y * zr1, z1);

        ballVerts.push_back(x * zr1); //X
        ballVerts.push_back(y * zr1); //Y
        ballVerts.push_back(z1);      //Z

        ballVerts.push_back(0.0f); 
        ballVerts.push_back(1.0f); 
        ballVerts.push_back(0.0f); 
        ballVerts.push_back(1.0f); //R,G,B,A

// Render code
Furthermore, I am rotating this circle, the rotation works fine, since I have light changing and it gives me an idea that, it is rotating and is infact a circle at least

glRotatef(Angle, 1.0f, 0.5f, 0.3f);

glBindBuffer(GL_ARRAY_BUFFER, VertexBufferObject[2]);
glEnableClientState(GL_VERTEX_ARRAY);
glVertexPointer(3, GL_FLOAT, 7*4, 0);

glDrawArrays(GL_TRIANGLE_STRIP, 0, 3200);

glBindBuffer(GL_ARRAY_BUFFER, 0);

Answer 1

First off all you need to check if lighting is currently enabled using glGetIntegerv(GL_LIGHTING,&i) and maybe turn it on glEnable(GL_LIGHTING).

Then setup the glMaterial(...), glLightModel(...), glLight(...), there is tutorial http://www.cse.msu.edu/~cse872/tutorial3.html

or you can use own GLSL shaders to apply some advanced illumination, some tutorials are here http://www.lighthouse3d.com/opengl/glsl/

In some trivial cases you can just pass vertex colors via glColor3f(…) instead of using the GL lighting.

Also normals should be unit vectors or enable normalization glEnable(GL_NORMALIZE).