[Tex/LaTex] Why (La)TeX can not work with true type fonts


I know that if one wants to use true type fonts, there are solutions via xelatex or lualatex.

My question however is, why it is like so? What is the fundamental difference between latex fonts and ttf that dictates this behavior and how [xe/lua]latex overcome this problem?

Best Answer

Well pdflatex can handle true type fonts to a certain extent. E.g. the winfonts package allows to use arial.ttf and other truetype fonts in windows. The main difference between pdftex and the new engines xetex and luatex is not the font format but

  1. the existence of the tfm-file with the metric informations: When using pdftex the tfm-file must exist before the compilation but xetex and luatex can create the information on the fly from the actual font.

  2. The number of glyphs in a font. pdftex can handle only 256 glyphs per tfm. So if the font has more glyphs you must create more than one tfm (and perhaps virtual fonts and .enc-files).

Setting up a font for pdftex needs some time. With xetex and luatex you can normally use it within minutes.