cam_pos      = [-0.222008, 0.646641, 1.23525]';
cam_dir      = [0.886563, 0.448131, 0.114826]';
cam_up       = [-0.445478, 0.760097, 0.473076]';
cam_lookat   = [0, 0, 1]';
cam_sky      = [0, 1, 0]';
cam_right    = [-0.165879, 0.62585, -1.16176]';
cam_fpoint   = [0, 0, 1]';
cam_angle    = 90;