Drawing order of shapes incorrect

            location = new Vector3(0f, -150f, -2000f);
            ObjectSelection(new Devices.Camera(htDefaultSettings, location), eACTION.CREATE);
            cameraMatrix = new Camera(htDefaultSettings, location);
            rotation = new Vector3(55,0,45);
            cameraMatrix.Bank = rotation.X;
            cameraMatrix.Heading = rotation.Y;
            cameraMatrix.Attitude = rotation.Z;

        private void Render()
        {
            if (cameraMatrix == null) return;
            try
            {
                GL.MatrixMode(MatrixMode.Modelview);
                GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
                Matrix4 m = cameraMatrix.Transformation;
                GL.LoadMatrix(ref m);
                cameraMatrix.Transformation = m;
 
                DrawGrid();
                ICollection vPrimitiveCollection = htObjects.Values;
                foreach (object o in vPrimitiveCollection)
                {
                    GL.PushMatrix();
                    if (o is Primitive.Box)             { DrawBox((Primitive.Box)o); }
                    else if (o is Primitive.Circle)     { DrawCircle((Primitive.Circle)o); }
                    else if (o is Primitive.Curve)      { DrawCurve(o); }
                    else if (o is Primitive.Font)       { DrawFont(o); }
                    else if (o is Primitive.Line)       { DrawLine(o); }
                    else if (o is Primitive.Plane)      { DrawPlane((Primitive.Plane)o); }
                    else if (o is Primitive.Sphere)     { DrawSphere((Primitive.Sphere)o); }
                    else if (o is Primitive.Torus)      { DrawTorus(o); }
                    else if (o is Primitive.Triangle)   { DrawTriangle(o); }
                    else if (o is Primitive.Tube)       { DrawTube((Primitive.Tube)o); }
                    GL.PopMatrix();
                }
            }
            catch (Exception em) { MessageBox.Show(em.Message); }
            glControl.SwapBuffers();
        }

        private void DrawBox(Primitive.Box p)
        {
            GL.Translate(p.TranslationX, p.TranslationY, p.TranslationZ);
            GL.Rotate(p.Heading, Vector3.UnitY);
            GL.Rotate(p.Attitude, Vector3.UnitZ);
            GL.Rotate(p.Bank, Vector3.UnitX);
            GL.Begin(BeginMode.Quads);
            for (int i = 0; i < p.Verticies.Length; i++)
            {
                GL.Color4(p.Color[i / 12]);
                GL.Vertex3(p.Verticies[i], p.Verticies[++i], p.Verticies[++i]);
                GL.Vertex3(p.Verticies[++i], p.Verticies[++i], p.Verticies[++i]);
                GL.Vertex3(p.Verticies[++i], p.Verticies[++i], p.Verticies[++i]);
                GL.Vertex3(p.Verticies[++i], p.Verticies[++i], p.Verticies[++i]);
            }
            GL.End();
            GL.Begin(BeginMode.Lines);
            for (int i = 0; i < p.Verticies.Length; i++)
            {
                GL.Color4(Color.Black);
                GL.Vertex3(p.Verticies[i], p.Verticies[++i], p.Verticies[++i]);
                GL.Vertex3(p.Verticies[++i], p.Verticies[++i], p.Verticies[++i]);
                GL.Vertex3(p.Verticies[++i], p.Verticies[++i], p.Verticies[++i]);
                GL.Vertex3(p.Verticies[++i], p.Verticies[++i], p.Verticies[++i]);
            }
            GL.End();
            if (oCurrentSelection == htObjects[p]) { DrawObjectCoordinate(p.Transformation); }
        }

        private void glControl_KeyDown(object sender, KeyEventArgs e)
        {
            if (!bGLControlLoaded) return;
            if (sender == null) return;
            try
            {   // Camera Control
                #region Pan Left/Right
                if (e.KeyCode == Keys.A)
                {
                    location.X -= 5f;
                }
                if (e.KeyCode == Keys.D)
                {
                    location.X += 5f;
                }
                #endregion
                #region Pan Up/Down
                if (e.KeyCode == Keys.W)
                {
                    location.Y += 5f;
                }
                if (e.KeyCode == Keys.S)
                {
                    location.Y -= 5f;
                }
                #endregion
                #region Zoom In/Out
                if (e.KeyCode == Keys.Q)
                {
                    location.Z += 10f;
                }
                if (e.KeyCode == Keys.Z)
                {
                    location.Z -= 10f;
                }
                #endregion
                #region Rotate Around Y
                if (e.KeyCode == Keys.R)
                {
                    rotation.X -= 2f;
                }
                if (e.KeyCode == Keys.T)
                {
                    rotation.X += 2f;
                }
                #endregion
                #region Rotate Around X
                if (e.KeyCode == Keys.F)
                {
                    rotation.Y -= 2f;
                }
                if (e.KeyCode == Keys.G)
                {
                    rotation.Y += 2f;
                }
                #endregion
                #region Rotate Around Z
                if (e.KeyCode == Keys.V)
                {
                    rotation.Z -= 2f;
                }
                if (e.KeyCode == Keys.B)
                {
                    rotation.Z += 2f;
                }
                #endregion
            }
            catch { }
 
            // Setup camera position in space
            cameraMatrix.TranslationX = location.X;
            cameraMatrix.TranslationY = location.Y;
            cameraMatrix.TranslationZ = location.Z; 
            cameraMatrix.Heading = rotation.Y;
            cameraMatrix.Attitude = rotation.Z;
            cameraMatrix.Bank = rotation.X;
            glControl.Invalidate();
 
        }