cam_pos      = [-0.602556, 1.24395, 0.806746]';
cam_dir      = [-0.36036, 0.231169, -0.903715]';
cam_up       = [0.90709, 0.312786, -0.281696]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.289342, 1.22528, 0.428801]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;