cam_pos      = [0.208967, 0.665831, -0.337269]';
cam_dir      = [0.876792, 0.274155, 0.395064]';
cam_up       = [-0.458184, 0.226924, 0.859403]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.194127, 1.24292, -0.43169]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;