说明：  读写ply文件的matlab实现。Writes a mesh to a ply file and Reads a ply file (text format). ply files can be in binary format as well
(Writes a mesh to a ply file (text format) wich can be read by PlyView from Cyberware and Scanalyze from Stanford University. Both are available for free. Reads a ply file (text format). ply files can be in binary format as well this function can read ply files in txt format only e.g. created by makePly.m.)