The FAQ for MetaPost drawing is why ghostview cannot preview the picture but you can still included in LaTeX. Actually, this is due to the fact that, MP output is not a completely valid postscript, but just a partial file. Whenever you included some text, it cannot understand where to find the font as the font-related header is missing. No way to fix, this is a feature!

However, I know it is annoying and it make some begineers confused. But I found two neat tools. First one is the mptopdf command, which is bundled in my Debian. It can convert the MP file directly into PDF pictures. Suitable for those pdflatex users. Another is the mptoeps Perl script, available at, which do the same thing but for a completely valid eps file. This probably help to relief some people’s pain.