manual/luatex-introduction.tex

   1 \environment luatex-style
   2 \environment luatex-logos
   3
   4 \startcomponent luatex-introduction
   5
   6 \startchapter[title=Introduction]
   7
   8 This book will eventually become the reference manual of \LUATEX. At the moment,
   9 it simply reports the behavior of the executable matching the snapshot or beta
  10 release date in the title page. We don't claim it is complete and we assume that
  11 the reader knows about \TEX\ as described in \quotation {The \TEX\ Book}, the
  12 \quotation {\ETEX\ manual}, the \quotation {\PDFTEX\ manual}, etc. Additional
  13 reference material is published in journals of user groups and \CONTEXT\ related
  14 documentation.
  15
  16 Features may come and go. The current version of \LUATEX\ can be used for
  17 production (in fact it is used in production by the authors) but users cannot
  18 depend on complete stability, nor on functionality staying the same. This means
  19 that when you update your binary, you also need to check if something fundamental
  20 has changed. Normally this is communicated in articles or messages to a mailing
  21 list. We're still not at version 1 but when we reach that state the interface
  22 will be stable. Of course we then can decide to move towards version 2 with
  23 different properties.
  24
  25 This means that occasionally you can encounter functionality not described here.
  26 Just consider that experimental then. They are either a playground or are being
  27 tested in real situations first before being finalized. And we can equally well
  28 kick them out again. When they stay we will descibe them in the manual or more
  29 extensively in articles.
  30
  31 Don't expect \LUATEX\ to behave the same as \PDFTEX ! Although the core
  32 functionality of that 8 bit engine is present, \LUATEX\ can behave different due
  33 to its wide (32 bit) characters, many registers and large memory support. There
  34 is native \UTF\ input, support for large (more that 8 bit) fonts, and the math
  35 machinery is tuned for \OPENTYPE\ math. Ther ei ssupport for directional
  36 typesetting too. The log output can differ from other engines and will likely
  37 differ more as we move forward. When you run plain \TEX\ for sure \LUATEX\ runs
  38 slower than \PDFTEX\ but when you run for instance \CONTEXT\ it might be faster. But
  39 in any case: 32 bit all||over combined with more features has a price.
  40
  41 \LUATEX\ consists of a number of interrelated but (still) distinguishable parts.
  42 The organization of the source code is adapted so that it cna glue all these
  43 components together. We continue cleaning up side effects of the accumulated
  44 code in \TEX\ engines (especially code that is not needed any longer).
  45
  46 \startitemize[packed]
  47     \startitem
  48         Most of \PDFTEX\ version 1.40.9, converted to C (with patches from later
  49         releases). Some experimental features have been removed and some utility
  50         macros are not inherited as their functionality can be done in \LUA. We
  51         still use the \type {\pdf*} primitive namespace.
  52     \stopitem
  53     \startitem
  54         The direction model and some other bits from \ALEPH\ RC4 (derived from
  55         \OMEGA) is included. The related primitives are part of core \LUATEX.
  56     \stopitem
  57     \startitem
  58         We currently use \LUA\ 5.2.*. At some point we might decide to move to
  59         5.3.* but that is yet to be decided.
  60     \stopitem
  61     \startitem
  62         There are few \LUA\ libraries that we consider part of the core \LUA\
  63         machinery.
  64     \stopitem
  65     \startitem
  66         There are additional \LUA\ libraries that interface to the internals of
  67         \TEX.
  68     \stopitem
  69     \startitem
  70         There are various \TEX\ extensions but only those that cannot be done
  71         using the \LUA\ interfaces.
  72     \stopitem
  73     \startitem
  74         The fontloader uses parts of \FONTFORGE\ 2008.11.17 combined with
  75         additionaL code specific for usage in a \TEX\ engine.
  76     \stopitem
  77     \startitem
  78         the \METAPOST\ library
  79     \stopitem
  80 \stopitemize
  81
  82 Neither \ALEPH's I/O translation processes, nor tcx files, nor \ENCTEX\ can be
  83 used, these encoding|-|related functions are superseded by a \LUA|-|based
  84 solution (reader callbacks). Most of the \PDFTEX\ backend is available but via a
  85 bit different interface.
  86
  87 The yearly \TEXLIVE\ version is the stable version, any version between them is
  88 considered beta. Keep in mind that new (or changed) features also need to be
  89 reflected in the macro package that you use.
  90
  91 \blank[3*big]
  92
  93 \starttabulate
  94 \NC \LUATEX   \EQ Version \number\luatexversion.\luatexrevision \NC \NR
  95 \NC \CONTEXT  \EQ \contextversion \NC \NR
  96 \NC timestamp \EQ \currentdate \NC \NR
  97 \stoptabulate
  98
  99 \stopchapter
 100
 101 \stopcomponent