Re: using \definebodyfont with multiple size declarations -- Why?

[Hans Hagen <pragma@wxs.nl>]

On 26-7-2010 11:36, Martin Althoff wrote:

> \definebodyfont [10pt,11pt,12pt] [rm] [tfe=Serif at 48pt, ite=SerifItalic at 48pt]
> \tfe Big {\it Words}.
>
> What I simply don't understand is the need for multiple font size declarations. I can (kind of) see that it might be necessary (looking at typescripts), if the whole typescript resolves to "design sizes" where each point size is a single font file. But for ttf/otf fonts, ie. where the font is scaled?

as mentioned, it originates in design sizes and finetuning

for most fonts you will see things like

\definetypeface [main] [rm] [serif] [palatino] [default]

this will use the default set

   \definebodyfont
     [4pt,5pt,6pt,7pt,8pt,9pt,10pt,11pt,12pt,14.4pt,17.3pt]
     [rm] [default]

in principle we could do without, but this helps predefining a couple of 
things that otherwise would slow down each font switch

it also relates to bodyfont environments where there are relationships 
between sizes

but anyhow, it's mostly a side effect of lm having design sizes

in practice, if you choose say 13pt it will work out ok  as things are 
checked and defined on the fly; but there might be a slight performance hit

> This minimal example, including a "special" font (TitleFont) works (almost) fine for me.
>
> % the only two statements to declare the fonts I want to use
> \usetypescriptfile[type-otf] % being default, I could even miss this declaration

sure, as that one is already part of the load-set

> \setupbodyfont[pagella,10pt]
>
> \definefont [WonderFont] [BoldItalic sa 4.8]

you probably want features enables, so "*default"

\definefont [WonderFont] [BoldItalic*default sa 4.8]

> \starttext
> {\WonderFont The Big Title}
> \input aesop-de
> \stoptext
>
> I do get one consistant error (the "5pt" can vary depending on the size I give in "setupbodyfont"):
>
> {/Users/martin/contextMini/tex/texmf-context/fonts/map/pdftex/context/mkiv-px.map}
> virtual math>  the mapping is incomplete for 'pxmath' at 5pt

harmless: it means that the math virtual font vector is not yet 
completely defined, and the message is only given once per set (i.e. 
pxmath) so in this case that happens to be the 5pt version (small sizes 
are defined as part of math setup)

> Though, the document looks fine. Does the error hint I am missing something? What is "good practice" in Luatex/MKIV to access the desired fonts?

using \definefont as you do is ok

>
> My questions:
>
> - when do I need to use the multiple point sizes at all in a Luatex/MKIV environment?

if you want an adaptive situation, so, in a title where you have only 
text, it' ok to use \definefont; when you expect things like math, 
smaller or larger sizes and style switches, you can best use a bodyfont 
switch

> - when would I need to provide that information in typescript files I need to create? (simplefonts is very slow to load fonts with phonetic symbols)

depends .. wolfgang might know the answer

Hans

-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
     tel: 038 477 53 69 | voip: 087 875 68 74 | www.pragma-ade.com
                                              | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________