On Wed, Jan 16, 2019 at 4:24 PM Wolfgang Schuster wrote:

User 19087 schrieb am 16.01.19 um 21:56:

...

I'm having trouble scaling down symbols and emojis. For a while I assumed these don't scale with the current font size. Then I scoured the mailing list and realized that while scaling down seems broken, scaling up works as expected: \tx (or \tfx, \bfx etc.) and \txx are ignored in some cases unlike the other size switches (\tfa etc.).

Out of curiosity, why are these switches sometimes ignored?

User 19087 schrieb am 17.01.19 um 14:30:

On Wed, Jan 16, 2019 at 4:24 PM Wolfgang Schuster wrote:

...

...

% Which factor should I use to match \tfxx? \symbol[ShortForty] \scale[factor=4]{\symbol[ShortForty]} x = 0.8 xx = 0.6 That's what the ConTeXt Reference Manual also says, but that doesn't seem to match what ConTeXt does. The 'x' ratio is 0.835 and the 'xx' ratio is 0.6667. The default sizes (12pt, 14.4pt etc,) set the x and xx sizes to a fixed size which leads to differences and the scale factor.

Below are the settings for the 12pt size from font-pre.mkiv: \definebodyfontenvironment   [12pt]   [x=10pt,    xx=8pt] Wolfgang

On Fri, Jan 18, 2019 at 4:44 PM User 19087 wrote:

There must be some other method (at least via luatex) to obtain the 'x' and 'xx' sizes as workable dimensions.

I've come up with the following macro and I'd like some feedback. Will it work consistently? Any suggestions for improvement? % A '\start...\stopluacode' block inside a macro is just as bad (or worse?) to % escape as '\ctxlua' code. So create a function here for use elsewhere. % % There were multiple font sizes in the "specification" and "parameters" % tables, hopefully I picked the right one. % % It turns out that for ConTeXt there is a difference between the 10pt and % 10.0pt sizes: the former is predefined in the body font environment that % ships with ConTeXt while the latter causes ConTeXt to generate a new body % font environment. Unfortunately '\the' displays values with trailing 0s, and % so the result must be converted to a string and truncated in lua. \startluacode userdata = userdata or {} userdata.fontsize = function () local fs fs = font.getfont(font.current()).specification.size fs = tostring(fs/2^16):gsub("%.?0+$","") .. "pt" return fs end \stopluacode % In some situations the 'tx' and 'txx' sizes are ignored by ConTeXt. This % macro determines the font size that would have been used by such a command % and switches the entire body font to that size for the duration of the second % argument. The chosen size depends on the 'x' and 'xx' values of the specific % body font environment nearest in size to the current body font, though the % font itself (via definebodyfont) may override those values. \define[2]\tosize{% % Use a scratch box to prevent any typesetting. Otherwise changes to the % font size would be compounded: 'tfxx' remaining in effect after % 'switchtobodyfont'. I've also tried stop...starthiding, but that prevents % all processing of contents. \setbox\scratchbox\hbox{% #1% % Use a global lua variable rather than globally setting a scratch % register. \startluacode userdata = userdata or {} userdata.lastfontsize = userdata.fontsize() \stopluacode% }% {\switchtobodyfont[\ctxlua{context(userdata.lastfontsize)}]#2}% } Test{\tfx Test} \tosize{\tfx Unwanted}{Test{\tfx Test}}

As far as I can tell (by experimentation), bodyfont environment features resolve in this order: * matching size in the current file * default environment in the current file * matching size in 'font-pre.mkiv' * default environment in 'font-pre.mkiv' * default to 1.0 otherwise This applies to individual features such as 'a' and 'b' and not entire blocks. For example, if the [12pt] block provides 'a' but not 'b' while the [default] block provides 'a' and 'b', then both blocks will be used: 'a' from [12pt] and 'b' from [default]. With one exception: the 'x' and 'xx' sizes cannot be modified by the current file: \setupbodyfont[12pt] \setupbodyfontenvironment [default] [x=2.0,xx=2.0] \starttext m{\tfx m}{\tfxx m} \stoptext Furthermore there seems to be some extraneous output when the bodyfontenvironment matches the current bodyfont size. For example, the following outputs: "m12.0ptm12.0ptm" \setupbodyfontenvironment [12pt] [m=2.0,n=2.0,] \starttext m{\tfm m}{\tfn m} \stoptext On Sat, Jan 19, 2019 at 3:59 AM Wolfgang Schuster wrote:

Why do you need this when you can just change the style of commands with use \tfx (e.g. \high or \low) to use the \tfm size?

With that out of the way, I don't know how to change commands which use '\tfx' to use '\tfm' instead. Unless you mean this (though technically they still use '\tfx', it just matches '\tfm'): \setupbodyfontenvironment [default] [m=0.8,n=0.6,x=0.8,xx=0.6] Even if that did work, which it doesn't (see above), it would be preferable to use the default bodyfont environment shipped by ConTeXt. It probably exists for good reasons: matching the most common optical font sizes, for aesthetics, and for consistency. I don't want the 'x' and 'xx' sizes to vary between standard ConTeXt documents, and documents which need to provide the 'n' and 'm' sizes. It's also more work, as mentioned further up the thread. It may not be strictly necessary to specify 'x' and 'xx' for each new size-specific bodyfont environment, as they'll be inherited from [default]. But for consistency each bodyfont size should have 'x' and 'xx' sizes matching those from ConTeXt, and these vary with bodyfont size. That means looking them up in 'font-pre.mkiv', a little math, and remembering to do it every time you switch sizes. And that's ignoring the fact that '\definebodyfont' can also override these sizes. I think using a macro is simpler.