- ntg-context - NTG Mailing Lists

Alternative for selector in LMTX for different heading and reference texts for descriptions
by Christoph Reller 25 Dec '20

25 Dec '20

Hi, In ConTeXt MKIV, there are selectors (\defineselector, \select). In ConTeXt LMTX, they are gone. In LMTX, how can I achieve the following without using selectors: (Different heading and reference texts for descriptions) \defineselector[sel][max=2, n=2] \definedescription[desc][headcommand={\setupselector[sel][n=1]}] \starttext \startdesc[title={\select{sel}{Long title}{Short}}, reference=desc] \input jojomayer \stopdesc \about[desc] \stoptext Any help is welcome! Cheers, Christoph

2 4

Check if two paths intersect in Metafun
by Jairo A. del Rio 25 Dec '20

25 Dec '20

Hi, list. I've got a question about paths and intersections. The following: \starttext \startMPpage path p[]; p[1] = fullcircle scaled 2cm; p[2] = unitsquare shifted (4cm,6cm); if (known (p[1] intersectionpoint p[2])): draw textext("yes"); else: draw textext("no"); fi; \stopMPpage \stoptext yields an error message: "The paths don't intersect". Is there a way to intercept this error message and trigger an action instead? Thank you in advance. Best regards, Jairo

2 1

MetaFun - "remove the paths of text" from a rectangle to let the background visible
by Garulfo 24 Dec '20

24 Dec '20

Hi, * I try to "remove the paths of text" from a metapost pictures to let the background visible. * Using https://mailman.ntg.nl/pipermail/ntg-context/2018/thread.html#92725 * I was able to get the following with one glyph (MVE code below) https://wiki.contextgarden.net/images/d/d2/test_extract_glyphs.pdf 2 questions: 1/ for some fonts (e.g. dejavu vs latin modern) the "encompassing" path of the B glyph can switch from B[1] to B[Bn]. Is there a trick to identify which id match with "the encompassing" path ? 2/ now, I would like to do the same, but for text... a kind of derivative of "textext" or "outlinetext". Would you please give me some guidelines ? does it already exist ? should I use something like \handletokens, \scantokens ? do you have examples where I can get inspiration ? Thanks again for your help, Garulfo %============================================================================== \starttext %------------------------------------------------------------------------------ \startluacode function document.outlinepaths(character) local chardata = fonts.hashes.characters[true] -- by unicode local shapedata = fonts.hashes.shapes[true] -- by index local c = chardata[character] if c and c.index and shapedata then local shapeglyphs = shapedata.glyphs or { } local glyph = shapeglyphs[c.index] if glyph and (glyph.segments or glyph.sequence) then local units = shapedata.units or 1000 local factor = 100/units return fonts.metapost.paths(glyph,factor) end end return { } end function document.defineoutline(char,target) local outlines = document.outlinepaths(char) local nofpaths = #outlines context("path %s[] ;",target) context("numeric %sn ; %sn := %s ;",target,target,nofpaths) for i=1,nofpaths do context("%s[%i] := %s ; ",target,i,outlines[i]) end end \stopluacode %------------------------------------------------------------------------------ \def\mpdefineoutlines#1#2{\ctxlua{document.defineoutline(\number`#1,"#2")}} %------------------------------------------------------------------------------ \startMPpage numeric dimA ; dimA := 20cm; path pathbackground ; pathbackground := unitsquare scaled dimA ; fill pathbackground withshademethod "linear" withshadedirection(0,1) withshadecolors (red,blue); %-------------------------------------- \mpdefineoutlines{B}{B} %-------------------------------------- numeric dimB ; dimB := 2cm; numeric vratio ; vratio := 2; path frame ; frame := unitsquare xscaled (dimA - 2 * dimB) yscaled (dimA / vratio) shifted (dimB , (dimA - (dimA / vratio))/2 ); %-------------------------------------- pair shift ; shift := center frame; numeric scal ; scal := (0.9) * (10cm / (bbheight B[1])) ; picture monImageB; monImageB := nullpicture; addto monImageB contour (B[1] shifted (- center B[1]) scaled scal) shifted shift withpostscript "collect"; addto monImageB contour frame withpostscript "evenodd"; for i=2 upto Bn : addto monImageB contour (B[i] shifted (- center B[1]) scaled scal) shifted shift; endfor ; %-------------------------------------- draw monImageB withcolor white; \stopMPpage \stoptext

4 7

Problem with \dfrac{}{} with lmtx updated
by Fabrice Couvreur 24 Dec '20

24 Dec '20

Hi, I just updated lmtx and I don't understand the error that occurs with the \dfrac{}{}. Thank you. Fabrice ##################### \starttext \m{f(x)=\dfrac{a + b\ln(x)}{x}} \stoptext ##################### tex error > tex error on line 2 in file ./hans_21.tex: Math error: parameter 'fractionnumup' in style 2 is not set <macro> \math_m_nop #1->\relax \ifmmode #1\else \normalstartimath #1\normalstopimath \fi <line 3.2> \m{f(x)=\dfrac{a + b\ln(x)}{x}} 1 \starttext 2 >> \m{f(x)=\dfrac{a + b\ln(x)}{x}} 3 \stoptext Sorry, but I can't typeset math unless various parameters have been set. This is normally done by loading special math fonts into the math family slots. Your font set is lacking at least the parameter mentioned earlier. mtx-context | fatal error: return code: 256 TeX Output exited abnormally with code 1 at Thu Dec 24 16:30:13

2 1

efficiently scaling fonts
by Hans Hagen 24 Dec '20

24 Dec '20

Hi, I uploaded a new lmtx ... in a previous mail i mentioned font scaling and I made that two dimensional: \starttext \setuplayout[topspace=1cm,header=1cm] \setuplayout[middle] \setupbodyfont[pagella,10pt] \setupalign[verytolerant,stretch] \setupwhitespace[big] \starttext \startbuffer \definescaledfont[bfe][xscale=2000,yscale=6000,style=bf] \setuphead[chapter][style=\bfe] \dostepwiserecurse {10} {2020} {10} { \title{Here we go #1!} \start \glyphxscale#1\relax \glyphyscale#1\relax \setupinterlinespace \samplefile{ward}% \start \bf \samplefile{ward}% \glyphxscale\numexpr(#1*2)/3\relax \glyphyscale#1\relax \samplefile{ward}% \par \stop \def\TEST{y = \sqrt{x^2 + 1}^3}% \dontleavehmode \ruledhbox{\glyphxscale #1 \glyphyscale #1 $\left{\TEST\right}$} \ruledhbox{\glyphxscale #1 \glyphyscale \numexpr#1*3\relax $\left{\TEST\right}$} \ruledhbox{\glyphxscale \numexpr#1/2\relax \glyphyscale \numexpr#1*2\relax $\left{\TEST\right}$} \par \stop \page } \stoptext Best use the high level interface: \definescaledfont [MyLargerFontB] [xscale=1200,yscale=2000,style=bold] test {\MyLargerFontB test {\em test} test} test etc. Math works too but I need to check soem details which I will do later. There are some conceptual decisions to be made there because we're nto so much talking of a font but of a 'setup of fonts and measures'. (Boldened math can be improved a bit, in general, unrelated to this feature.) Hans ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------

2 1

Missing kerns with latest 22.12.2020 LMTX
by Joseph 24 Dec '20

24 Dec '20

2 1

Re: [NTG-context] Hyphenation pattern for Esperanto
by Alain Delmotte 23 Dec '20

23 Dec '20

3 3

a new book has been published, made with the help of ConTeXt
by Robert Zydenbos 23 Dec '20

23 Dec '20

Dear readers, With great joy and a sense of relief I can now announce that my latest book, _A Manual of Modern Kannada_ by Robert Zydenbos (Heidelberg / Berlin: CrossAsia E-Publishing, 2020), a teaching manual of the Kannada language (Kannada belongs to the Dravidian family of languages, mainly spoken in southern India; also in the city of Bangalore, the 'Silicon Valley of India') has been published. It is an Open Access publication, which means it is available as a gratis download in PDF format from https://crossasia-books.ub.uni-heidelberg.de/xasia/catalog/book/736 (the clickable button “Buch herunterladen” means “Download book”; “Buch kaufen” means “Buy book”, for those who want a real book on paper). I was working on this book for the past few years and decided that the only affordably sensible way to achieve presentable results would be to use TeX, but plain TeX was too cumbersome, and in LaTeX the tables were difficult (and the book has many, many tables in various shapes and sizes). ConTeXt was The Solution (and has been duly mentioned in the technical note at the end of the book, with special thanks to Hans, Wolfgang and Pablo for valuable suggestions). For those who are curious how I used ConTeXt MkII with the XeTeX backend, a sample chapter is available at http://e.pc.cd/XlhotalK (and then click on "Direkt herunterladen"). Robert Zydenbos

2 2

new font trickery
by Hans Hagen 23 Dec '20

23 Dec '20

Hi, I finally decided to start an experiment that I had on my todo list for a while: dynamically scaling fonts. Below is an example of usage (plus some comment). In that example some 2*200 different font sizes are used which in mkiv demands 400 font definitions. This costs time and memory. The example below runs (on my old laptop) in less than 2 seconds and only uses two instances. I bet that our CJK users will love it. I post it because: (1) I need to discuss the impact with Wolfgang ... how do we integrate this. We can for instance define some sizes (\tfa \tfb ...) differently. (2) I want to see if average performance improves on huge documents with many fonts / sizes (that is for Massimiliano to test). (3) Are there side effects? It does work for math (rather neat trickery) but maybe we need an additional configration for that. (4) I considered several variants but for now use a low level \glyphscale command that takes a number (in goodl old tex tradition a scale of 1.0 is entered as 1000). (5) The implementation can be improved a bit (performance wise). There is a bit more overhead involved but usually I can compensate that. (6) It will not be backported to MKIV so one can only test in LMTX. it's a bit of a mix between engine and context features. (7) There can be bugs (unforseen side effects, or typos in the somewhat quick patches in the source). Consider it an experiment, but so far I'm rather satisfied, Hans %%%% EXAMPLE %%%% \setuplayout[middle] \setupbodyfont[pagella,10pt] \setupalign[verytolerant,stretch] \setupwhitespace[big] \starttext \startbuffer \definescaledfont[bfe][scale=2000,style=bf] \setuphead[chapter][style=\bfe] \dostepwiserecurse {10} {2020} {10} { \title{Here we go #1!} \start \glyphscale#1\relax \setupinterlinespace \samplefile{ward}% \bf \samplefile{ward} \par \stop \page } \stopbuffer \getbuffer \title{Scaled fonts} Although \CONTEXT\ is quite efficient with fonts there is always room for improvement. However, after years of finetuning the font mechanisms there was not that much room left. This made me think of a different approach to scaling. Nowadays fonts seldom come in design sizes. Also, in \CONTEXT\ \MKIV\ and therefore \LMTX\ we always had so called dynamic features: apply additional features locally, although that comes with a small penalty in performance, it saves additional font instances. It is a good approach for the occasional small stretch of glyphs, like small capped logos and such. We now can also do dynamic font scaling, which means that we don't need to define a new font instance when the same feature set is used. Or course in addition to this features one can still use the dynamic features. This means that for instance chapter titling can use the bodyfont instance and just apply additional scaling. Although for a normal run the number of loaded fonts is normally small, and the number of instances also isn't that impressive it can happen in a large document that you end up with a few dozen. That number can now be reduced to half a dozen. Of course there can be side effects, whcich is why it's currently tagged as experimental. There is also a small performance hit because we now need to track it but that is gained back because we load less fonts and have less glyph runs. It even works in math, although there some different trickery is needed. \typebuffer \stoptext ----------------------------------------------------------------- Hans Hagen | PRAGMA ADE Ridderstraat 27 | 8061 GH Hasselt | The Netherlands tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl -----------------------------------------------------------------

2 2

cow-font
by Peter Münster 23 Dec '20

23 Dec '20

Hi, How could I make use of the cow-font please? I've tried this test-file: --8<---------------cut here---------------start------------->8--- \setupbodyfont[cow] \starttext test \stoptext --8<---------------cut here---------------end--------------->8--- But the page is empty. With version 2017.08.29 it worked well... TIA for any help, -- Peter

3 3