(calc_pixel_width_or_height): Use actual display

resolution when available instead of Vdisplay_pixels_per_inch.

diff --git a/src/xdisp.c b/src/xdisp.c
index 9b5b7edf035141c1f4da8050e5caeee0163d9711..6ed5fd151d609405d7bec70b60a0a81e2f196c4c 100644 (file)
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -17622,6 +17622,15 @@ calc_pixel_width_or_height (res, it, prop, font, width_p, align_to)
          if (pixels > 0)
            {
              double ppi;
+#ifdef HAVE_WINDOW_SYSTEM
+             if (FRAME_WINDOW_P (it->f)
+                 && (ppi = (width_p
+                            ? FRAME_X_DISPLAY_INFO (it->f)->resx
+                            : FRAME_X_DISPLAY_INFO (it->f)->resy),
+                     ppi > 0))
+               return OK_PIXELS (ppi / pixels);
+#endif
+
              if ((ppi = NUMVAL (Vdisplay_pixels_per_inch), ppi > 0)
                  || (CONSP (Vdisplay_pixels_per_inch)
                      && (ppi = (width_p
@@ -23056,7 +23065,7 @@ of the top or bottom of the window.  */);
   scroll_margin = 0;
 
   DEFVAR_LISP ("display-pixels-per-inch",  &Vdisplay_pixels_per_inch,
-    doc: /* Pixels per inch on current display.
+    doc: /* Pixels per inch value for non-window system displays.
 Value is a number or a cons (WIDTH-DPI . HEIGHT-DPI).  */);
   Vdisplay_pixels_per_inch = make_float (72.0);