What is the God-level operation that today's Tex users cannot imagine in the ancient times of Tex users? _ Ancient times

Liu Haiyang Li Aling and 26 people agree that the ancient times of Tex users have a god-level operation unimaginable to today's Tex users. Tex is not the most complex of the software, and the Tex code is less complicated than a decent programming language. Not to mention that the document is not playing video games, so the so-called "God-level operation" is not in fact, this name also makes me feel strange.

Moreover, the development of computer software is becoming more and more complex. Constrained by computer performance and people's brain holes, twenty or thirty of years ago people wrote the TeX code is far less complex today. Like Pgfplots, a tens of thousands of-line TeX-code monster that can be used to compute a 3D surface with macros, it's hard to imagine an era in which a thicker book has been used to worry about low memory.

There are probably two kinds of technology, the basic and important things that have been used from the past to the present, and the one that fades away over time and is not known, which is generally the technology of elimination. In ancient times, and today's people can not imagine the technology, most of them are not adapt to the development of the time and obsolete things. So there is no need to imitation in technology, and it is not the same as the more ancient cheats in wuxia novels.

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As for what's special about the early TeX code, look for the code to see. For example, there is a small macro in Macros for the Art of the Computer programming, which is this:

\newdimen\bitmapsize \bitmapsize=10pt
{\catcode ' \.=\active
  \gdef\bitmap#1: #2: #3: #4: #5: #6 < #7 >% EMS: Cols:rows:-hoff:rows+voff
The \bitmap of this is to use input parameters as lattice data, directly using \special output as a bitmap of PostScript code.

 

The macro actually uses this:

 
\bitmap74:1.08:72:72:-3:60% G4156 <0003800000000000000003c00000000000000001e00000000000000000f0000000000000%
 0000fc00000000000000007c00000000007000007c0000000001fc00007e0700000003fe%
 00007e0f8fffffffff00007e1fc7ffffffff00007c3fe3fffffffc3ffffffff001f001f8%
 1ffffffff801f001f8080000300001f000f80000003c0001f000f80000007e0001f000f8%
 00e0007f0001f000f80070007f0001f000f80038007e0001f000f8003c007c0001f000f8%
 001e00f80003f000f8001f00f00003e000f8000f81f00003e001f8000fc1e00003c001f8%
 000fc3c00007c001f0000fc3c00007c001f0000f8780f0078003f0000f8781f80f8003f0%
 00070f01fc0f0007e000000f03fe1f3f07e0ffffffffff1e3fffe07fffffffff3c07ffc0%
 3c000000003800ff80000000000078007f800000000000f0003f000000000001e0003800%
 01c0001c03c000200001f0001f070000000001fc003f8e0000000001ffffffcce00001e0%
 01ffffffc8f80001f001f8001f00fe0003f801f8001f00fffffffc01f8001f00fffffffc%
 01f8001f007c0003f801f8001f007c0003f001f8001f007c0003f001f8001f007c0003f0% 01f8001f007c0003f001f8001f007c0003f001ffffff007c0003f001ffffff007c0003f0% 01f8001f007c0003f001f8001f007c0003f001f8001f007c0003f001f8001f007c0003f0%
 01f8001f007c0003f001f8001f007c0003f001f8001f007c0003f001f8001f007c0003f0%
 01f8001f007c0003f001f8001f007c0003f001ffffff007c0003f001ffffff007c0003f0%
 01ffffff007ffffff001f8001f007ffffff001f8001f007c0003f001f8001f007c0003f0%
 01f8001f007c0003f001f8001f00fc0003f001f8000000fc0003f001f8000000fc0003c0% >%% Unicode Char "97f6
In fact, is Qinjiushao "Shao" word. Use Dvips to build it up, zoom in, look long.

 

See here is understood, this is a processing of individual lattice word of the soil method.

 

This kind of thing today's TeX users are really not easy to imagine. But this kind of code does not feel that this kind of thing is the divine level operation. At least my first feeling was that I might as well do an EPS picture illustration directly. Edited in 2016-06-12 to add a comment thank you share · no help • Report • Author Reserve right Li Aling Belleve and so on 29 people agree with the big Eagle asked me to answer this question, I was in Qinghai Ningxia area activities, so there is no time to answer.

The complexity of the language of Tex has been talked about a lot before, and the computational language, the macro language is very trick can play, simple, directly change the \catcode, add a quantitative macro so you can implement Basic or Lisp in Tex interpreter. The use of \expandafter and \let and other trick also play, plus some number of registers or dimen registers can implement some recursive macros. For this can play things, beginners use the texbook can, want to cookbook will need to see Victor Eijkhout this book:

The book of the Times earlier, initially serialized on the tugboat, basically the standard TeX82 in the trick are fully covered. Download Victoreijkhout/tex by Topic. Of course, Victor Eijkhout also has a book called The Computer Science of Tex and Latex, which is suitable for people with a little computer base to read (for example, to understand the principles of compiling), visible the Computer of Tex and LaTeX.

 

The above mentioned change Catcode, the simplest most intuitive can refer to the following address: Introduction to Poor man's Chinese TeX. Namely Poor man's Chinese TeX Simplified, Central Institute of Research Center, ASPAC plan. When I saw this thing, it was really stupid, a little computer foundation, the code of this article read down for half a month to understand. This time can be wasted, but it is suitable for the university to waste. The previous encoding were Double-byte encodings, and the way to change Catcode was the simplest and most efficient, but now it's not entirely applicable, especially after Unicode. (By the way, I found what I wrote earlier: How to quickly see the implementation of the LaTeX Macro command.) -LaTeX)

 

The Chinese character processing in the 90 's, especially under the DOS system, has a large number of lattice font processing scenes. Both the Poorman method, the CJK approach, and the CCT approach, the center is not a dot-matrix font. Among the old CCT, there's a tool that specializes in dot-matrix, and I've been in touch with this part of the last month, but it's pretty much out of use now. This kind of thing is not a very face, but a result of the lack of that time.

 

And one thing worth mentioning is Omega. This thing to Tex. The length of the patch is almost the length of the Tex code itself. The omega itself has a complex typesetting function, and the OTP/OCP can enable it to handle many complex language texts. But the thing itself is outdated because it is so cumbersome that developers are a handful of people. Unlike other engines, such as XeTeX control layout engine, documents are written clearly, and it is not difficult to write macros to control. Omega part of the function, now in the LuaTeX can also be seen, but these features are also perfunctory.

 

In the drawing technology, there used to be xy-pic and pstricks. But now is basically a few independent drawing language +tikz the world. On the one hand, these languages and TikZ in the design of a more modern, in the application library is also very rich, coupled with the page description language and a variety of driving macro development scale is larger, so many old bags are not used much. Pstricks this thing, is through the \special to add PostScript code, and finally in the DVI parsing, this part of the code inserted into the PS file, this kind of thing is really popular in the 90 's, even have a special processing to PS engine Vtex ( Micropress home Page). However, with the popularity of PDF since 2000, the use of PS gradually decline, the community inside the PS processing tools are not much richer than the PDF, more or less rely on Ghostscript, and even dvips now do not support bitmap file illustrations.

 

There is an interesting thing, such as the German students said there are still many people in Germany in the use of plain Tex, I am not too surprised, for English and so on, in fact, plain very useful, but also a part of the Russians are now also used plain Tex. To play Chinese characters under plain Tex, XeTeX and LuaTeX are more or less possible except for the Ptex system, depending on the particular package and a specific set of macros. I started writing some small test files in the plain format in 2012. The degree of freedom is very high, of course, this is only refers to the grammar, want a specific style, latex or convenient.

from:https://www.zhihu.com/question/47175617#answer-37694377