* subr.el (posn-col-row): Properly compute line spacing.

Suggested by Nikolaj Schumacher (Bug#2933).

2 files changed, 18 insertions, 7 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 163b3e21ab9..88d37ed22a0 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,8 @@
+2009-04-15  Chong Yidong  <cyd@stupidchicken.com>
+
+        * subr.el (posn-col-row): Properly compute line spacing.
+        Suggested by Nikolaj Schumacher (Bug#2933).
+
 2009-04-15  Ulf Jasper  <ulf.jasper@web.de>
 
         * net/newst-treeview.el (newsticker-treeview-jump): Enable virtual
diff --git a/lisp/subr.el b/lisp/subr.el
index ffe8a9de5b1..5372adb510c 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -930,13 +930,19 @@ and `event-end' functions."
       (cons (scroll-bar-scale pair (window-width window)) 0))
      (t
       (let* ((frame (if (framep window) window (window-frame window)))
-             (x (/ (car pair) (frame-char-width frame)))
-             (y (/ (cdr pair) (+ (frame-char-height frame)
-                                 (or (frame-parameter frame 'line-spacing)
-                                     ;; FIXME: Why the `default'?
-                                     (default-value 'line-spacing)
-                                     0)))))
-        (cons x y))))))
+             ;; FIXME: This should take line-spacing properties on
+             ;; newlines into account.
+             (spacing (when (display-graphic-p frame)
+                        (or (with-current-buffer (window-buffer window)
+                              line-spacing)
+                            (frame-parameter frame 'line-spacing)))))
+        (cond ((floatp spacing)
+               (setq spacing (truncate (* spacing
+                                          (frame-char-height frame)))))
+              ((null spacing)
+               (setq spacing 0)))
+        (cons (/ (car pair) (frame-char-width frame))
+              (/ (cdr pair) (+ (frame-char-height frame) spacing))))))))
 
 (defun posn-actual-col-row (position)
   "Return the actual column and row in POSITION, measured in characters.