cam_pos      = [-0.55992, 1.69936, 1.59274]';
cam_dir      = [0.938695, -0.342767, -0.0369198]';
cam_up       = [0.296201, 0.856664, -0.422364]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.234612, -0.512763, -1.20455]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;