cam_pos      = [-0.477396, 0.900257, 0.741181]';
cam_dir      = [-0.582511, 0.447224, -0.678728]';
cam_up       = [0.812799, 0.326903, -0.482174]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.00829693, 1.10728, 0.736724]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;