cam_pos      = [-0.489386, 1.00998, 1.68589]';
cam_dir      = [0.880245, 0.464294, -0.0979795]';
cam_up       = [-0.421375, 0.859764, 0.28853]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.290209, 0.282879, -1.26675]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;