1. When working under different Unix or Windows systems, the following sysmtem files may be needed: opengl32.dll, glut.dll, glut32.dll, glu32.dll and glut.h Not all sysmtems have all the above files. 2. It is possible that the program does not work under some special settings. Consultation with the author is recommanded, if you meet any technical problem. 3. Any modification and publication of this software need to be authorized by the author.