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- PostScript Chess Font -- "README" file.
- ========== ===== ==== == ======== =====
-
- Copyright (c) 1991 A. N. Walker. All rights reserved.
-
- Restrictions on Use:
- ------------ -- ----
- You must keep the copyright notice on this file and on the
- accompanying "Font" file. If you change anything, you must clearly
- mark your changes. Otherwise, you may use these files as you please
- for private, educational or research purposes. You may also use them
- freely for commercial purposes as long as you do not make any changes
- to the shapes of the pieces without my approval.
-
- I do not, and am in no position to, make any claim as to
- suitability of these files for any specific purpose. They work for
- me, and if they work for you too I shall be pleased. If they do not
- work for you, well, you have what you paid for.
-
- If you are pleased with the results, please let me [and your
- readers, if any!] know. If you manage to make money out of them,
- please let me know how! I'd quite like to see [real or PostScript]
- copies of what you manage to do, if you have the necessary time,
- inclination and resources.
-
- If you don't like the results, please let me know why. Indeed,
- if you have any comments, please e- or snail- mail them to me.
-
- What you have to do:
- ---- --- ---- -- ---
- You should have three files, called "Font", "Demo" and "Table".
- If you have a way of viewing PostScript, shovel "Font" and "Demo" or
- "Font" and "Table" at it; for example, I use the commands
-
- lpr -Plwriter Font Demo
- lpr -Plwriter Font Table
-
- to see the results on "my" LaserWriter. If you have no way of viewing
- PostScript, then I'm sorry, but I can't help you. What you should see
- is an assorted collection of boards and figurines in various sizes and
- rotations ("Demo") or a neat table showing all the symbols in the font
- ("Table"). If anything else happens, you will have to consult someone
- who knows what they're doing -- *not* me! I can promise you that the
- files as shipped print nicely on a bog-standard Apple LW+. They take
- several minutes each to print on our LW+; this is largely because they
- make almost pessimal use of the font caching mechanism -- lots of big
- characters are printed once each in different sizes and orientations.
- Conventional pages with lots of figurines or ordinary text and only a
- few diagrams print acceptably quickly (especially, of course, if you
- have a faster or more recent LW).
-
- If you are happy with the demos, you can then install the "Font"
- file as a font in your system.
-
- ****************************************
- * I cannot help you with this process! *
- ****************************************
-
- I can't even do it for our own computer, which has a much-hacked (from
- its PDP-11 days) version of Troff; I leave it to our guru. Neither
- he nor I know what magic you have to utter for an unhacked Troff, or
- for TEX, or for Macs or PCs or whatever weird and wonderful software
- or hardware you possess. When you install the font, you may also find
- it useful to grab some of the PostScript code from "Demo", especially
- if you want to draw (for example) labelled diagrams.
-
- What there is in the Font:
- ---- ----- -- -- --- -----
- There are really two fonts wrapped up into one. The more
- conventional sub-font is the so-called "text mode", and is what you
- get when you first select the font. This mode itself has two major
- components. The upper case letters are the figurines, for use in
- text. For example, "Q" draws a queen figurine. Lower case letters
- and other symbols are (most of) the Informant symbols (omitting only
- symbols like "?" and "ch" that you can reasonably expect to find in
- boring old Times Roman, but including "+" and "-"). I've been as
- mnemonic as I could, but there are just too many symbols.
-
- The other sub-font is "diagram mode". In this, upper case
- letters draw white pieces, and lower case letters draw black pieces.
- For example, "Knk" draws a white king adjacent to a black knight
- and a black king. The pieces include a selection of fairy pieces
- and other related symbols -- everything I've seen or had reported
- to me on chess diagrams in the last few years. The other symbols
- in this sub-font consist of board-drawing components and motions
- to facilitate the construction of diagrams. You switch between
- text and diagram modes using the prime symbol, "'". For example,
- the famous Reti study can be diagrammed by the PostScript:
-
- ('#[7K;8;k1P;7p;8;8;8;8]') show
-
- where "#" draws the board, and the stuff between "[...]" is the
- conventional Forsythe notation for the position. Obviously, for
- practical use, you will need a chess pre-processor (which I have
- *not* written!).
-
- Most of the capabilities of the font are illustrated on
- the demo page, which also includes some possibly-useful PostScript
- procedures for various of the effects.
-
- Warning: the dual-mode font treads on very thin ice in
- some places! In particular, the caching mechanisms of PostScript
- are very easy to fool with a dynamic font of this type. For example,
- finding the width of a string is fraught with danger; do it only
- with strings that include matched pairs of primes.
-
- The font design:
- --- ---- -------
- There are surprisingly many different chess fonts in use in
- printed books. I have tried to copy the simplest -- for example,
- the rooks have no brickwork, and the kings are quite plain. Note
- that the pieces do not scale well. Large pieces (inches high) for
- posters, etc., will have to be specially designed (and are usually
- based on "real" Staunton pieces). Tiny pieces suffer from the lack
- of resolution on 300 dpi (or coarser) printers. On a 300 dpi printer,
- 7-point is really too small, anything less is hopeless (see the demo).
- I usually use 15-point, which is comparable with most books.
-
- The hardest piece to get right is the knight. The book designs
- are hopeless at 300 dpi resolution, as there are too many fine lines
- around the mouth and chin. Any attempts to copy them just look like a
- caricature. So I've made it a bit chunkier. Most readers don't notice.
-
- Note that most of the pieces (as opposed to the figurines)
- cannot be cached. This is because they include both write-white and
- write-black components (partly, but not entirely, because they have
- to work on black squares); this makes drawing a whole page of black
- kings (or whatever) rather slooow. Fortunately, you don't often need
- such a thing. The figurines *are* cached, so are the Informant symbols,
- and so are the commonest pieces (the black squares, and the pawns of
- both colours).
-
- Foreign usage:
- ------- ------
- Foreign users may want to re-assign the letters used for the
- various pieces. This can easily be done in the Font file. Lines
- such as
-
- dup 8#113 /WK put % 'K'
-
- (not too far down the file) signify that ASCII character 113 (octal), or
- "K", is to draw the White King. If you want some other character to draw
- the WK, alter the 113 to match. You will have to change the BK and Kfig
- by the same amount, and you will also have to reassign whatever symbol
- your chosen character already draws, if any. Another minor problem is
- that some of the fairy pieces are defined explicitly in terms of the
- existing pieces -- eg, if you decide to use "F" to draw White queens,
- then the procedure for Grasshoppers (look for "WG" in Font) must be
- changed to draw upside-down "F" instead of upside-down "Q". I hope the
- necessary edits are obvious even to non-PostScript users. I suggest that
- after any change you try the Table and Demo files again.
-
- Unusual chess pieces:
- ------- ----- -------
- I've included a fair number of pieces that may not be familiar to
- all chess players. These include:
- F for fou, French version of bishop. There are several designs
- of fou in print, I have selected the easiest to implement. If
- you want one of the others, you'll have to write it yourself.
- D,X for draughts pieces. Note that these are not cached (except
- as figurines); if you are writing a book on draughts with
- lots of diagrams, you might find it worthwhile to re-write
- them in a cachable way. This is easier if you want to use
- them on the white squares (you don't need the "halo" effect),
- but the books I have seen are about equally split on this.
- C,I,T for chameleon, imitator, rose. Various fairy pieces.
- E,G,L,M,O,S,U,V,Z for various rotated standard pieces, used in
- fairy chess. Note that the "Demo" file includes a more
- general way to rotate a piece. I have used S for nightrider,
- oppositely to the problemists convention which uses S for
- knight and N for nightrider; there is no way that the average
- player is going to change his habits! If you are a problemist,
- feel free to interchange S and N (and then M and Z).
- .,@,|,_ for various other marks useful in annotating diagrams.
- See the "Demo" file for examples of their use.
- A,H,J,W,Y are unused. Feel free to use them to add new pieces.
-
- Go pieces:
- -- -------
- Sorry, despite several requests, I haven't put these in. I
- can't save the whole world in one easy lesson. The pieces themselves
- and the board are easy in PostScript; the annotations and the necessary
- pre-processor are another kettle of fish. The Go stones could also be
- used for Reversi (Othello).
-
- Bridge symbols:
- ------ --------
- No-one has actually asked for these, but just to forestall you,
- note that they are already provided in many places -- symbol fonts,
- dingbats fonts, Hershey fonts, ....
-
- Final comments:
- ----- ---------
- Suggestions for improvements, especially in the PostScript,
- will be welcomed. Especially if they improve portability (which I
- can't check locally!). Especially if you've tried them yourself,
- and can vouch that they work. Suggestions for extra symbols (other
- than Go or Bridge) also welcomed, especially if accompanied by
- PostScript or other descriptions of their shape.
-
- --
- Andy Walker, Maths Dept., Nott'm Univ., UK.
- anw@maths.nott.ac.uk
-