How To: Render a fixed red size sphere in scene

Below is sample code on how to create a fixed size sphere(red) in scene.
Size of the sphere does not change when you zoom.

    HC_Open_Segment_By_Key(m_pHView->GetModelKey()); {

        float cube[24] = {
          -1.0f, -1.0f, -1.0f,
           1.0f, -1.0f, -1.0f,
          -1.0f,  1.0f, -1.0f,
           1.0f,  1.0f, -1.0f,
          -1.0f, -1.0f,  1.0f,
           1.0f, -1.0f,  1.0f,
          -1.0f,  1.0f,  1.0f,
           1.0f,  1.0f,  1.0f };

        int conn[30] = {
          4, 0,1,3,2,
          4, 1,5,7,3,
          4, 5,4,6,7,
          4, 4,0,2,6,
          4, 2,3,7,6,
          4, 4,5,1,0 };

        HC_Open_Segment(""); {
            HC_Insert_Shell(8, cube, 30, conn);

            HC_Open_Segment(""); {
                // Translate red sphere to the corner of cube
                HC_Translate_Object(1, 1, 1);
                HC_Open_Segment(""); {
                    float center[] = { 0,0, 0 };
                    // Sphere need to be created at the origin
                    HC_Insert_Sphere(center, 0.1f, NULL, NULL);
                    HC_Set_Color("Red");
                    HC_Set_Rendering_Options("mask transform=(camera=(scale))");
                } HC_Close_Segment();
            } HC_Close_Segment();
        } HC_Close_Segment();
    } HC_Close_Segment();

Video:

fixed_size