cam_pos      = [-0.423075, 1.73874, 1.75808]';
cam_dir      = [0.883663, -0.416239, -0.214209]';
cam_up       = [0.284342, 0.840758, -0.460734]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.494591, -0.460478, -1.14553]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;