cam_pos      = [0.181937, 1.01345, 0.665153]';
cam_dir      = [0.56827, 0.400263, -0.718929]';
cam_up       = [-0.758639, -0.0834869, -0.64614]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [0.423801, -1.21374, -0.340762]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;