Hi Tassilo, >>>>> Tassilo Horn <[email protected]> writes: > Grzegorz Kowzan <[email protected]> writes: > Hi Grzegorz,
>>> I guess the problem is that mm-size in the `frame-monitor-attributes' >>> return value differs from `display-mm-height' and `display-mm-width'. >> >> 1) Yes, `display-pixel/mm-width/height` functions are defined in terms >> of Xlib calls, whereas `frame-monitor-attributes` calls Gdk functions >> (if Emacs was compiled with Gtk support) and only as a fallback it >> calls Xlib. This is why we have this inconsistency. The standard DPI >> for Xorg server is 96 regardless of the actual value, so for a given >> resolution and assumed DPI Xorg gives fake mm width and >> height. Essentially, the current calculation of DPI in auctex looks >> pointless to me... > Ok, I see. >> With pure Gtk port we get actual physical pixel width/height and >> actual mm width/height, so I guess when auctex detects pgtk port, it >> can either ignore these values and hardcode DPI of 96 or make use of >> the actual DPI. I suppose there is something to be said for not >> changing auctex's behaviour and hardcoding the value, but I would >> prefer to use the actual DPI at least as an option (see below). > That's what I did. Essentially I've applied your patch with an > additional fboundp check for `frame-monitor-attributes'. If it's > available (24.4), then your variant is used, if not, the previous > variant basically always saying 96 DPI is used. Isn't it a good time to carry out this TODO in preview.el.in? ;-) ,---- | (defun preview-get-dpi () | ;; TODO: Remove false-case when required emacs version is bumped to | ;; 24.4 or newer as this is the version where | ;; `frame-monitor-attributes' has been introduced. | (if (fboundp 'frame-monitor-attributes) | (let* ((monitor-attrs (frame-monitor-attributes)) | (mm-dims (cdr (assoc 'mm-size monitor-attrs))) | (mm-width (nth 0 mm-dims)) | (mm-height (nth 1 mm-dims)) | (pixel-dims (cdddr (assoc 'geometry monitor-attrs))) | (pixel-width (nth 0 pixel-dims)) | (pixel-height (nth 1 pixel-dims))) | (cons (/ (* 25.4 pixel-width) mm-width) | (/ (* 25.4 pixel-height) mm-height))) | (cons (/ (* 25.4 (display-pixel-width)) | (display-mm-width)) | (/ (* 25.4 (display-pixel-height)) | (display-mm-height))))) `---- And I'd like to comment on two minor aspects. 1. The function `cdddr' used above isn't yet available for emacs 25.1, so it should be replaced with `cl-cdddr'. I noticed this thanks to a byte compile log which Michael Braun sent me off list. Thank you, Michael! (And this means that preview-latex didn't work at all for emacs 25.1 for this 1.5 years!) 2. Though bug#20171[1] is still open, I hope it has already been resolved as well with this bug#45596. If so, let's close it, too. Best, Ikumi Keita #StandWithUkraine #StopWarInUkraine [1] https://debbugs.gnu.org/cgi/bugreport.cgi?bug=20171
