Hello Pablo,

thank you for showing the way; unfortunately, still something is 
missing:

- the resulting file uses LMRoman instead of WorkSans,

- the log confirms:

"selectfont      > The requested font 'WorkSans' has no files for the 
'tf' alternative, Latin Modern is used instead".

- Note that all WorkSans files:

   work-sans.bold.otf
   work-sans.bold-italic.otf
   work-sans.light.otf
   work-sans.light-italic.otf

     are placed in the same directory as the main source file. (I can zip 
them and upload somewhere for testing purposes.)

- In your code bellow, I cann't see any link to any work-sans .otf file 
name.

   - Does it mean that that ConTeXt browses its database of "known" 
fonts, searches for all fonts which contain "identification" as 
"WorkSans" (given from your \definefontfamily...[WorkSans])?

- Also, I see assignments [tf={style:light},it={style:lightitalic}]:

   - Should also an assignment for "bf=[style:...]" be provided?

   - How ConTeXt gets to know from "it={style:lightitalic}" that file 
"work-sans.light-italic.otf" should be used?

Sorry for elementary questions, I'm still "in captivity" of swtching 
fonts, their styles and font sizes by clicking a combo in Word toolbar 
(although I quit using Word about 15 ys ago). And although I'm aware of 
different dealing with fonts in TeX (and in professional typesetting in 
general), it's often difficult for me to imagine how exactly TeX 
switchches fonts, what is the relationship between (and how the comands 
cooperate) \definefontfamily, \setupbodyfontenvironment, \setupbodyfont, 
\definefontsynonym, \definefont, typescripts, simplefonts module and 
also what is the relations among parameters to the-above commands.

So any practical samples (e.g. here discussed) helps me much.

Best regards,

Lukas


> Hi Lukas,
> 
> I think this is what you might need:
> 
>     \definefontfamily
>         [mainface]
>         [rm]
>         [WorkSans]
>         [tf={style:light}, it={style:lightitalic}]
>     \setupbodyfont[mainface]
> 
>     \setupbodyfontenvironment
>         [default]
>         [a=1.2,
>          b=2.4,
>          c=3.6,
>          d=4.8,
>          em=italic]
> 
>     \starttext
>     \startTEXpage[offset=1em]
>         roman\\
>         {\bf bold}\\
>         {\it italic}\\
>         {\bi bold italic}\\
>         {\tfa roman}\\
>         {\bfb bold}\\
>         {\itc italic}\\
>         {\bid bold italic}\\
>     \stopTEXpage
>     \stoptext
> 
> I hope it helps,
> 
> Pablo
> --
> http://www.ousia.tk
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