Question about cmtex fonts

Question

The question concerns info on this page.

The extended ASCII font, cmtex10, has the parameters of cmtt10, except that the slant is positive (for a few characters that will be slanted).

What is the meaning of the phrase "except that the slant is positive"?

Which exactly are these "few characters that will be slanted"?

cfr · Accepted Answer · 2016-02-25T02:01:09.747

Here's a diff of the two MetaFont sources:

diff fonts/source/public/cm/cmtt10.mf fonts/source/public/cm/cmtex10.mf

yields

1c1
< % THIS IS THE OFFICIAL COMPUTER MODERN SOURCE FILE cmtt10.mf BY D E KNUTH.
---
> % THIS IS THE OFFICIAL COMPUTER MODERN SOURCE FILE cmtex10.mf BY D E KNUTH.
4c4
< % Computer Modern Typewriter Text for use with 10 point
---
> % Computer Modern TeX extended ASCII characters for use with 10 point
7c7
< font_identifier:="CMTT"; font_size 10pt#;
---
> font_identifier:="CMTEX"; font_size 10pt#;
62c62
< slant:=0;      % tilt ratio $(\Delta x/\Delta y)$
---
> slant:=.25;      % tilt ratio $(\Delta x/\Delta y)$
78c78
< generate roman      % switch to the driver file
---
> generate texset      % switch to the driver file

To see what this means in detail, it is easier to look at the AFMs provided by AMS with the type1 drop-in replacements for these fonts:

diff fonts/afm/public/amsfonts/cm/cmtt10.afm  fonts/afm/public/amsfonts/cm/cmtex10.afm

produces considerably more output. First the basic font parameters:

3,4c3,4
< FontName CMTT10
< FullName CMTT10
---
> FontName CMTEX10
> FullName CMTEX10
7c7
< Notice (Copyright (c) 1997, 2009 American Mathematical Society (<http://www.ams.org>), with Reserved Font Name CMTT10.)
---
> Notice (Copyright (c) 1997, 2009 American Mathematical Society (<http://www.ams.org>), with Reserved Font Name CMTEX10.)
14c14
< FontBBox -4 -233 537 696
---
> FontBBox -23 -233 537 694

Here, we can see the effect of the different slants.

And then many differences due to the fact that the two fonts contain differ in the characters they include. This is the effect of inputting different 'driver' files in the sources above. roman corresponds to the basic TeX text encoding and the variants for the similar encodings used for typewriter etc.:

input romanu;  % upper case (majuscules)
input romanl;  % lower case (minuscules)
input greeku;  % upper case Greek letters
input romand;  % numerals
input romanp;  % ampersand, question marks, currency sign
input romspl;  % lowercase specials (dotless \i, ligature \ae, etc.)
input romspu;  % uppercase specials (\AE, \OE, \O)
input punct;  % punctuation symbols common to roman and italic text
input accent;  % accents common to roman and italic text

texset corresponds to TeX's extended ASCII encoding:

input romanu;  % upper case (majuscules)
input romanl;  % lower case (minuscules)
input romand;  % numerals
input romanp;  % ampersand, question marks, currency sign
input punct;  % punctuation symbols common to roman and italic text
input tset;  % remaining special symbols of extended ASCII

These differences can be seen in the AFMS:

20,52c20,52
< C 0 ; WX 525 ; N Gamma ; B 32 0 488 611 ;
< C 1 ; WX 525 ; N Delta ; B 34 0 490 623 ;
< C 2 ; WX 525 ; N Theta ; B 56 -11 468 622 ;
< C 3 ; WX 525 ; N Lambda ; B 29 0 495 623 ;
< C 4 ; WX 525 ; N Xi ; B 33 0 491 611 ;
< C 5 ; WX 525 ; N Pi ; B 22 0 502 611 ;
< C 6 ; WX 525 ; N Sigma ; B 40 0 484 611 ;
< C 7 ; WX 525 ; N Upsilon ; B 38 0 486 622 ;
< C 8 ; WX 525 ; N Phi ; B 40 0 484 611 ;
< C 9 ; WX 525 ; N Psi ; B 38 0 486 611 ;
< C 10 ; WX 525 ; N Omega ; B 32 0 492 622 ;
< C 11 ; WX 525 ; N arrowup ; B 59 0 465 611 ;
< C 12 ; WX 525 ; N arrowdown ; B 59 0 465 611 ;
< C 13 ; WX 525 ; N quotesingle ; B 217 328 307 622 ;
< C 14 ; WX 525 ; N exclamdown ; B 212 -233 312 389 ;
< C 15 ; WX 525 ; N questiondown ; B 62 -228 462 389 ;
< C 16 ; WX 525 ; N dotlessi ; B 78 0 455 431 ;
< C 17 ; WX 525 ; N dotlessj ; B 48 -228 368 431 ;
< C 18 ; WX 525 ; N grave ; B 117 477 329 611 ;
< C 19 ; WX 525 ; N acute ; B 195 477 407 611 ;
< C 20 ; WX 525 ; N caron ; B 101 454 423 572 ;
< C 21 ; WX 525 ; N breve ; B 86 498 438 611 ;
< C 22 ; WX 525 ; N macron ; B 73 514 451 577 ;
< C 23 ; WX 525 ; N ring ; B 181 499 343 619 ;
< C 24 ; WX 525 ; N cedilla ; B 162 -208 428 45 ;
< C 25 ; WX 525 ; N germandbls ; B 17 -6 495 617 ;
< C 26 ; WX 525 ; N ae ; B 33 -6 504 440 ;
< C 27 ; WX 525 ; N oe ; B 19 -6 505 440 ;
< C 28 ; WX 525 ; N oslash ; B 43 -140 481 571 ;
< C 29 ; WX 525 ; N AE ; B 23 0 499 611 ;
< C 30 ; WX 525 ; N OE ; B 29 -11 502 622 ;
< C 31 ; WX 525 ; N Oslash ; B 56 -85 468 696 ;
< C 32 ; WX 525 ; N visiblespace ; B 44 -132 480 240 ;
---
> C 0 ; WX 525 ; N dotmath ; B 200 244 325 369 ;
> C 1 ; WX 525 ; N arrowdown ; B 58 1 466 612 ;
> C 2 ; WX 525 ; N alpha ; B 72 -6 502 437 ;
> C 3 ; WX 525 ; N beta ; B -23 -222 516 617 ;
> C 4 ; WX 525 ; N logicaland ; B 44 -11 480 535 ;
> C 5 ; WX 525 ; N logicalnot ; B 44 36 480 360 ;
> C 6 ; WX 525 ; N element ; B 66 55 458 557 ;
> C 7 ; WX 525 ; N pi ; B 39 -6 522 431 ;
> C 8 ; WX 525 ; N lambda ; B 47 -6 488 611 ;
> C 9 ; WX 525 ; N gamma ; B 58 -233 517 437 ;
> C 10 ; WX 525 ; N delta ; B 90 -7 476 645 ;
> C 11 ; WX 525 ; N arrowup ; B 58 1 466 612 ;
> C 12 ; WX 525 ; N plusminus ; B 38 137 486 587 ;
> C 13 ; WX 525 ; N circleplus ; B 38 81 486 531 ;
> C 14 ; WX 525 ; N infinity ; B 29 -6 495 437 ;
> C 15 ; WX 525 ; N partialdiff ; B 79 -11 529 622 ;
> C 16 ; WX 525 ; N propersubset ; B 56 55 468 557 ;
> C 17 ; WX 525 ; N propersuperset ; B 56 55 468 557 ;
> C 18 ; WX 525 ; N intersection ; B 44 -11 480 535 ;
> C 19 ; WX 525 ; N union ; B 44 -11 480 535 ;
> C 20 ; WX 525 ; N universal ; B 0 -11 524 611 ;
> C 21 ; WX 525 ; N existential ; B 52 0 472 611 ;
> C 22 ; WX 525 ; N circlemultiply ; B 38 81 486 531 ;
> C 23 ; WX 525 ; N arrowboth ; B 29 -52 495 664 ;
> C 24 ; WX 525 ; N arrowleft ; B 29 131 495 481 ;
> C 25 ; WX 525 ; N arrowright ; B 29 131 495 481 ;
> C 26 ; WX 525 ; N notequal ; B 38 -42 486 653 ;
> C 27 ; WX 525 ; N lozenge ; B 15 59 509 553 ;
> C 28 ; WX 525 ; N lessequal ; B 56 -21 468 631 ;
> C 29 ; WX 525 ; N greaterequal ; B 56 -21 468 631 ;
> C 30 ; WX 525 ; N equivalence ; B 38 120 486 492 ;
> C 31 ; WX 525 ; N logicalor ; B 44 -11 480 535 ;
> C 32 ; WX 525 ; N space ; B 0 0 0 0 ;
65c65
< C 45 ; WX 525 ; N hyphen ; B 56 271 468 341 ;
---
> C 45 ; WX 525 ; N minus ; B 56 271 468 341 ;
147,148c147,148
< C 127 ; WX 525 ; N dieresis ; B 110 512 414 612 ;
< C 128 ; WX 525 ; N visiblespace ; B 44 -132 480 240 ;
---
> C 127 ; WX 525 ; N integral ; B 55 -233 469 622 ;
> C 128 ; WX 525 ; N space ; B 0 0 0 0 ;
150,159c150,159
< C 161 ; WX 525 ; N Gamma ; B 32 0 488 611 ;
< C 162 ; WX 525 ; N Delta ; B 34 0 490 623 ;
< C 163 ; WX 525 ; N Theta ; B 56 -11 468 622 ;
< C 164 ; WX 525 ; N Lambda ; B 29 0 495 623 ;
< C 165 ; WX 525 ; N Xi ; B 33 0 491 611 ;
< C 166 ; WX 525 ; N Pi ; B 22 0 502 611 ;
< C 167 ; WX 525 ; N Sigma ; B 40 0 484 611 ;
< C 168 ; WX 525 ; N Upsilon ; B 38 0 486 622 ;
< C 169 ; WX 525 ; N Phi ; B 40 0 484 611 ;
< C 170 ; WX 525 ; N Psi ; B 38 0 486 611 ;
---
> C 161 ; WX 525 ; N dotmath ; B 200 244 325 369 ;
> C 162 ; WX 525 ; N arrowdown ; B 58 1 466 612 ;
> C 163 ; WX 525 ; N alpha ; B 72 -6 502 437 ;
> C 164 ; WX 525 ; N beta ; B -23 -222 516 617 ;
> C 165 ; WX 525 ; N logicaland ; B 44 -11 480 535 ;
> C 166 ; WX 525 ; N logicalnot ; B 44 36 480 360 ;
> C 167 ; WX 525 ; N element ; B 66 55 458 557 ;
> C 168 ; WX 525 ; N pi ; B 39 -6 522 431 ;
> C 169 ; WX 525 ; N lambda ; B 47 -6 488 611 ;
> C 170 ; WX 525 ; N gamma ; B 58 -233 517 437 ;
162,185c162,185
< C 173 ; WX 525 ; N Omega ; B 32 0 492 622 ;
< C 174 ; WX 525 ; N arrowup ; B 59 0 465 611 ;
< C 175 ; WX 525 ; N arrowdown ; B 59 0 465 611 ;
< C 176 ; WX 525 ; N quotesingle ; B 217 328 307 622 ;
< C 177 ; WX 525 ; N exclamdown ; B 212 -233 312 389 ;
< C 178 ; WX 525 ; N questiondown ; B 62 -228 462 389 ;
< C 179 ; WX 525 ; N dotlessi ; B 78 0 455 431 ;
< C 180 ; WX 525 ; N dotlessj ; B 48 -228 368 431 ;
< C 181 ; WX 525 ; N grave ; B 117 477 329 611 ;
< C 182 ; WX 525 ; N acute ; B 195 477 407 611 ;
< C 183 ; WX 525 ; N caron ; B 101 454 423 572 ;
< C 184 ; WX 525 ; N breve ; B 86 498 438 611 ;
< C 185 ; WX 525 ; N macron ; B 73 514 451 577 ;
< C 186 ; WX 525 ; N ring ; B 181 499 343 619 ;
< C 187 ; WX 525 ; N cedilla ; B 162 -208 428 45 ;
< C 188 ; WX 525 ; N germandbls ; B 17 -6 495 617 ;
< C 189 ; WX 525 ; N ae ; B 33 -6 504 440 ;
< C 190 ; WX 525 ; N oe ; B 19 -6 505 440 ;
< C 191 ; WX 525 ; N oslash ; B 43 -140 481 571 ;
< C 192 ; WX 525 ; N AE ; B 23 0 499 611 ;
< C 193 ; WX 525 ; N OE ; B 29 -11 502 622 ;
< C 194 ; WX 525 ; N Oslash ; B 56 -85 468 696 ;
< C 195 ; WX 525 ; N visiblespace ; B 44 -132 480 240 ;
< C 196 ; WX 525 ; N dieresis ; B 110 512 414 612 ;
---
> C 173 ; WX 525 ; N delta ; B 90 -7 476 645 ;
> C 174 ; WX 525 ; N arrowup ; B 58 1 466 612 ;
> C 175 ; WX 525 ; N plusminus ; B 38 137 486 587 ;
> C 176 ; WX 525 ; N circleplus ; B 38 81 486 531 ;
> C 177 ; WX 525 ; N infinity ; B 29 -6 495 437 ;
> C 178 ; WX 525 ; N partialdiff ; B 79 -11 529 622 ;
> C 179 ; WX 525 ; N propersubset ; B 56 55 468 557 ;
> C 180 ; WX 525 ; N propersuperset ; B 56 55 468 557 ;
> C 181 ; WX 525 ; N intersection ; B 44 -11 480 535 ;
> C 182 ; WX 525 ; N union ; B 44 -11 480 535 ;
> C 183 ; WX 525 ; N universal ; B 0 -11 524 611 ;
> C 184 ; WX 525 ; N existential ; B 52 0 472 611 ;
> C 185 ; WX 525 ; N circlemultiply ; B 38 81 486 531 ;
> C 186 ; WX 525 ; N arrowboth ; B 29 -52 495 664 ;
> C 187 ; WX 525 ; N arrowleft ; B 29 131 495 481 ;
> C 188 ; WX 525 ; N arrowright ; B 29 131 495 481 ;
> C 189 ; WX 525 ; N notequal ; B 38 -42 486 653 ;
> C 190 ; WX 525 ; N lozenge ; B 15 59 509 553 ;
> C 191 ; WX 525 ; N lessequal ; B 56 -21 468 631 ;
> C 192 ; WX 525 ; N greaterequal ; B 56 -21 468 631 ;
> C 193 ; WX 525 ; N equivalence ; B 38 120 486 492 ;
> C 194 ; WX 525 ; N logicalor ; B 44 -11 480 535 ;
> C 195 ; WX 525 ; N space ; B 0 0 0 0 ;
> C 196 ; WX 525 ; N integral ; B 55 -233 469 622 ;

And here are font tables for cmtt10 and cmtex10 obtained using pdflatex nfssfont:

As can be seen, a few characters in the second font are slanted e.g. beta.

I'm not sure what you mean about the TFM files. The slant is not included here because it is not a property of the font as a whole. It is used only in drawing particular glyphs. But the TFM doesn't contain information about how the glyphs should be drawn - only how big boxes they require. 'Slant' means something different in the .mf and the .tfm. The equivalent of the TFM SLANT is, I think, the italic slant which is zero for both of the fonts in question.

Is it possible not to use AFM in the answer? Let's stick to bitmap pk files. I do not understand how this slant influences typesetting if it is not in tfm files. — Igor Liferenko, Feb 25 '16 at 01:46
Please see edit above. You can trace the character lists through the .mf files if you wish. But you need to follow the trail of inputs to see the full effect. You can't look at the listing of characters all in one place as you can for the AFM. The slant from the .mf doesn't get into the .tfm because it is irrelevant there. Since .pk is a binary format, I don't see how to 'stick to' it in answering. Either you trace the tangle of .mfs or you look at the corresponding .afm. But the AFM doesn't directly show the slant - only the effect - because, like the TFM, it is just about boxes. — cfr, Feb 25 '16 at 02:05
Now I understand that the description says about another slant, not related to tfm files. How to use pk format? In a clean directory I do this: touch psfonts.map and view with xdvi testfont.dvi (testfont.dvi is created by tex testfont) — Igor Liferenko, Feb 25 '16 at 02:17
I know how to use PK files in typesetting. I don't understand how to use them to answer your question. You have to look at the .mf. The TFM helps a little, maybe, but the AFM is more help. (The info is all in the MFs but it is spread among many files.) You can't read a .pk. It's a binary format. It makes no odds which you use to generate a font table. Both PFB and PK are binary. They are both using the same TFM. They are both derived from the MFs. — cfr, Feb 25 '16 at 02:29

Question about cmtex fonts

1 Answers1