cam_pos      = [-0.258917, 0.517908, 1.42463]';
cam_dir      = [0.880245, 0.464294, -0.0979795]';
cam_up       = [-0.391984, 0.827837, 0.401291]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.355679, 0.418721, -1.21122]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;