基于四边形的网格通常使用Catmull-Clark，而基于三角形的网格通常使用环细分
https://ww2.mathworks.cn/matlabcentral/fileexchange/24942-loop-subdivision
https://ww2.mathworks.cn/matlabcentral/fileexchange/27982-wavefront-obj-toolbox?s_tid=srchtitle
function write_wobj(OBJ,fullfilename)
function read_wobj(fullfilename)
https://ww2.mathworks.cn/matlabcentral/fileexchange/18957-readobj?s_tid=srchtitle
function obj = readObj(fname)