On Sun, Feb 01, 2009 at 07:38:15PM +0000, imacarthur wrote: > > On 1 Feb 2009, at 14:24, cage wrote: > >> > >> If you change the '18' to '*' then it should wildcard > >> the size so that FLTK can control the sizes. > > > > I was expecting this too, but on my system the size of the rendered > > text do not change, i have write this few lines > > to check this behaviour: > > That *might* not be so surprising - the XLFD fonts used by Xlib tend, > in general, to be older types of fonts, often bitmap fonts, and often > not truly scalable. > So there is a real chance that the font that is being picked using > the XLFD name perhaps only exists on your machine in a single pitch, > with no scaling information in the font. > So as a result, the font that gets picked on the basis of this name, > does not then respond to scaling requests... > > > > > ./test -*-courier-medium-r-*-*-*-*-*-*-*-*-*-* > > > > give a fixed font size even if we are forcing to draw the text with > > a size of 49 but if you do: > > > > ./test courier > > > > on my system all works fine... > > I would assume that in this case, the font that gets picked for just > "courier" is a scalable font, whereas the one that gets picked for "- > *-courier-medium-r-*-*-*-*-*-*-*-*-*-*" is perhaps not... > Is the same face getting picked in both cases? I assume not. Pick a > few key glyphs and check if they are the same shape or not in each case. > > Anyway, an option is this; rather than setting the XLFD size to *, > try setting it to the size you actually want, and when you change the > font size, call set_font(....) again, with the new size inserted in > the string.
Unfortunately this would not be an optimal solution for me because not all sizes beetween a given range are available for a XLFD font :-( > Note also that XLFD names allow you to specify either > POINT size or PIXEL size in the name (I have no idea what happens if > you set both in an incompatible way!) so you may get different > results with either. The details are here, if you really need to > know. It's not the most exciting read though! > > http://ftp.xfree86.org/pub/XFree86/4.5.0/doc/xlfd.txt > > I would expect that as you change the sizes in the XLFD name, you may > actually get different font faces at different sizes, as the font > engine tries to find a match that can support the size you are > requesting... > > Alternately, if you can find a fully scalable font installed on your > system, that has the face you want, then selecting that is probably > the best bet, as then the renderer can deal with the sizing and > scaling issues for you. I think this is the best solution available... > However, it would appear that the face the font engine is picking, on > your system, when given the name "courier" is a scalable font, but > not *actually* a courier face... > > There are a whole bunch of extra font sets that can be installed on a > debian system, but most are not installed by default. They tend to > heavily favour the FOSS/libre fonts, as you might expect. > So you may find that you can apt-get some extra font packages and get > a much better, scalable, courier face from one of them. > > Or just accept, as I have learned, that font rendering is a mess. these are wise words! :-) At this time, as you explained me, i have realized that i should force both the screen and the export rendering to use the same font. Hovewer libplot is really old and only permits to specify a few postscript and PCL font, so i think i will switch library for a recent one, i was thinking cairo+pango. So thank you really thank you to you and greg for this thread because i have a way to try to exit from this nightmare now! :-D Bye! C. _______________________________________________ fltk mailing list [email protected] http://lists.easysw.com/mailman/listinfo/fltk
