Re: Emacs's set-frame-size can not work well with gnome-shell?

[martin rudalics <rudalics@gmx.at>]

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 > And it's not what my previous complaints were about. A drift is not
 > simply a lag. Lag rights itself at the end of the cursor motion (you
 > just have to wait a little). Drift doesn't right itself: the cursor
 > ends up at a certain distance from the the point of the frame it has
 > been dragging.

I've rewritten the mouse code completely, patch attached.  It neither
fixes the GTK child frame resizing problem nor the jumping issues in
Lucid but should provide better dragging of frames via internal borders
and mode-/header-line otherwise.  In particular the drift you mentioned
above should be gone now.  Please try it.

martin

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diff --git a/lisp/mouse.el b/lisp/mouse.el
index e58a2e6da1..bacee65436 100644
--- a/lisp/mouse.el
+++ b/lisp/mouse.el
@@ -552,7 +552,7 @@ mouse-drag-mode-line
              (not (eq (window-frame minibuffer-window) frame))))
       ;; Drag frame when the window is on the bottom of its frame and
       ;; there is no minibuffer window below.
-      (mouse-drag-frame start-event 'move)))))
+      (mouse-drag-frame-move start-event)))))
 
 (defun mouse-drag-header-line (start-event)
   "Change the height of a window by dragging on its header line.
@@ -569,7 +569,7 @@ mouse-drag-header-line
         (mouse-drag-line start-event 'header)
       (let ((frame (window-frame window)))
         (when (frame-parameter frame 'drag-with-header-line)
-          (mouse-drag-frame start-event 'move))))))
+          (mouse-drag-frame-move start-event))))))
 
 (defun mouse-drag-vertical-line (start-event)
   "Change the width of a window by dragging on a vertical line.
@@ -577,46 +577,7 @@ mouse-drag-vertical-line
   (interactive "e")
   (mouse-drag-line start-event 'vertical))
 \f
-(defun mouse-resize-frame (frame x-diff y-diff &optional x-move y-move)
-  "Helper function for `mouse-drag-frame'."
-  (let* ((frame-x-y (frame-position frame))
-         (frame-x (car frame-x-y))
-         (frame-y (cdr frame-x-y))
-         alist)
-    (if (> x-diff 0)
-        (when x-move
-          (setq x-diff (min x-diff frame-x))
-          (setq x-move (- frame-x x-diff)))
-      (let* ((min-width (frame-windows-min-size frame t nil t))
-             (min-diff (max 0 (- (frame-inner-width frame) min-width))))
-        (setq x-diff (max x-diff (- min-diff)))
-        (when x-move
-          (setq x-move (+ frame-x (- x-diff))))))
-
-    (if (> y-diff 0)
-        (when y-move
-          (setq y-diff (min y-diff frame-y))
-          (setq y-move (- frame-y y-diff)))
-      (let* ((min-height (frame-windows-min-size frame nil nil t))
-             (min-diff (max 0 (- (frame-inner-height frame) min-height))))
-        (setq y-diff (max y-diff (- min-diff)))
-        (when y-move
-          (setq y-move (+ frame-y (- y-diff))))))
-
-    (unless (zerop x-diff)
-      (when x-move
-        (push `(left . ,x-move) alist))
-      (push `(width . (text-pixels . ,(+ (frame-text-width frame) x-diff)))
-            alist))
-    (unless (zerop y-diff)
-      (when y-move
-        (push `(top . ,y-move) alist))
-      (push `(height . (text-pixels . ,(+ (frame-text-height frame) y-diff)))
-            alist))
-    (when alist
-      (modify-frame-parameters frame alist))))
-
-(defun mouse-drag-frame (start-event part)
+(defun mouse-drag-frame-resize (start-event part)
   "Drag a frame or one of its edges with the mouse.
 START-EVENT is the starting mouse event of the drag action.  Its
 position window denotes the frame that will be dragged.
@@ -635,9 +596,140 @@ mouse-drag-frame
          (frame (if (window-live-p window)
                     (window-frame window)
                   window))
-         (width (frame-native-width frame))
-         (height (frame-native-height frame))
-         ;; PARENT is the parent frame of FRAME or, if FRAME is a
+	 ;; Initial "first" frame position and size.  While dragging we
+	 ;; base all calculations against that size and position.
+	 (first-pos (frame-position frame))
+	 (first-left (car first-pos))
+	 (first-top (cdr first-pos))
+	 (first-width (frame-text-width frame))
+	 (first-height (frame-text-height frame))
+	 ;; Don't let FRAME become less large than the size needed to
+	 ;; fit all of its windows.
+	 (min-text-width
+	  (+ (frame-windows-min-size frame t nil t)
+	     (- (frame-inner-width frame) first-width)))
+	 (min-text-height
+	  (+ (frame-windows-min-size frame nil nil t)
+	     (- (frame-inner-height frame) first-height)))
+	 ;; PARENT is the parent frame of FRAME or, if FRAME is a
+         ;; top-level frame, FRAME's workarea.
+         (parent (frame-parent frame))
+         (parent-edges
+          (if parent
+              (frame-edges parent)
+            (let* ((attributes
+                    (car (display-monitor-attributes-list)))
+                   (workarea (assq 'workarea attributes)))
+              (and workarea
+                   `(,(nth 1 workarea) ,(nth 2 workarea)
+                     ,(+ (nth 1 workarea) (nth 3 workarea))
+                     ,(+ (nth 2 workarea) (nth 4 workarea)))))))
+         (parent-left (and parent-edges (nth 0 parent-edges)))
+         (parent-top (and parent-edges (nth 1 parent-edges)))
+         (parent-right (and parent-edges (nth 2 parent-edges)))
+         (parent-bottom (and parent-edges (nth 3 parent-edges)))
+	 ;; Drag types.  drag-left/drag-right and drag-top/drag-bottom
+	 ;; are mutually exclusive.
+	 (drag-left (memq part '(bottom-left left top-left)))
+	 (drag-top (memq part '(top-left top top-right)))
+	 (drag-right (memq part '(top-right right bottom-right)))
+	 (drag-bottom (memq part '(bottom-right bottom bottom-left)))
+	 ;; Initial "first" mouse position.  While dragging we base all
+	 ;; calculations against that position.
+	 (first-x-y (mouse-absolute-pixel-position))
+         (first-x (car first-x-y))
+         (first-y (cdr first-x-y))
+         (exitfun nil)
+         (move
+          (lambda (event)
+            (interactive "e")
+            (when (consp event)
+              (let* ((last-x-y (mouse-absolute-pixel-position))
+		     (last-x (car last-x-y))
+		     (last-y (cdr last-x-y))
+		     (left (- last-x first-x))
+		     (top (- last-y first-y))
+		     alist)
+                ;; We never want to warp the mouse position here.  When
+                ;; moving the mouse leftward or upward, then with a wide
+                ;; border the calculated left or top position of the
+                ;; frame could drop to a value less than zero depending
+                ;; on where precisely the mouse within the border.  We
+                ;; guard against this by never allowing the frame to
+                ;; move to a position less than zero here.  No such
+                ;; precautions are used for the right and bottom borders
+                ;; so with a large internal border parts of that border
+                ;; may disappear.
+                (when (and drag-left (>= last-x parent-left)
+                           (>= (- first-width left) min-text-width))
+		  (push `(left . ,(max (+ first-left left) 0)) alist)
+		  (push `(width . (text-pixels . ,(- first-width left))) alist))
+	        (when (and drag-top (>= last-y parent-top)
+                           (>= (- first-height top) min-text-height))
+		  (push `(top . ,(max 0 (+ first-top top))) alist)
+		  (push `(height . (text-pixels . ,(- first-height top))) alist))
+	        (when (and drag-right (<= last-x parent-right)
+                           (>= (+ first-width left) min-text-width))
+		  (push `(width . (text-pixels . ,(+ first-width left))) alist))
+	        (when (and drag-bottom (<= last-y parent-bottom)
+                           (>= (+ first-height top) min-text-height))
+		  (push `(height . (text-pixels . ,(+ first-height top))) alist))
+	        (modify-frame-parameters frame alist)))))
+         (old-track-mouse track-mouse))
+    ;; Start tracking.  The special value 'dragging' signals the
+    ;; display engine to freeze the mouse pointer shape for as long
+    ;; as we drag.
+    (setq track-mouse 'dragging)
+    ;; Loop reading events and sampling the position of the mouse.
+    (setq exitfun
+          (set-transient-map
+           (let ((map (make-sparse-keymap)))
+             (define-key map [switch-frame] #'ignore)
+             (define-key map [select-window] #'ignore)
+             (define-key map [scroll-bar-movement] #'ignore)
+             (define-key map [mouse-movement] move)
+             ;; Swallow drag-mouse-1 events to avoid selecting some other window.
+             (define-key map [drag-mouse-1]
+               (lambda () (interactive) (funcall exitfun)))
+             ;; Some of the events will of course end up looked up
+             ;; with a mode-line, header-line or vertical-line prefix ...
+             (define-key map [mode-line] map)
+             (define-key map [header-line] map)
+             (define-key map [vertical-line] map)
+             ;; ... and some maybe even with a right- or bottom-divider
+             ;; prefix.
+             (define-key map [right-divider] map)
+             (define-key map [bottom-divider] map)
+             map)
+           t (lambda () (setq track-mouse old-track-mouse))))))
+
+(defun mouse-drag-frame-move (start-event)
+  "Drag a frame or one of its edges with the mouse.
+START-EVENT is the starting mouse event of the drag action.  Its
+position window denotes the frame that will be dragged.
+
+PART specifies the part that has been dragged and must be one of
+the symbols `left', `top', `right', `bottom', `top-left',
+`top-right', `bottom-left', `bottom-right' to drag an internal
+border or edge.  If PART equals `move', this means to move the
+frame with the mouse."
+  ;; Give temporary modes such as isearch a chance to turn off.
+  (run-hooks 'mouse-leave-buffer-hook)
+  (let* ((echo-keystrokes 0)
+	 (start (event-start start-event))
+         (window (posn-window start))
+         ;; FRAME is the frame to drag.
+         (frame (if (window-live-p window)
+                    (window-frame window)
+                  window))
+         (native-width (frame-native-width frame))
+         (native-height (frame-native-height frame))
+	 ;; Initial "first" frame position and size.  While dragging we
+	 ;; base all calculations against that size and position.
+	 (first-pos (frame-position frame))
+	 (first-left (car first-pos))
+	 (first-top (cdr first-pos))
+	 ;; PARENT is the parent frame of FRAME or, if FRAME is a
          ;; top-level frame, FRAME's workarea.
          (parent (frame-parent frame))
          (parent-edges
@@ -654,19 +746,16 @@ mouse-drag-frame
          (parent-top (and parent-edges (nth 1 parent-edges)))
          (parent-right (and parent-edges (nth 2 parent-edges)))
          (parent-bottom (and parent-edges (nth 3 parent-edges)))
-         ;; `pos-x' and `pos-y' record the x- and y-coordinates of the
-	 ;; last sampled mouse position.  Note that we sample absolute
-	 ;; mouse positions to avoid that moving the mouse from one
-	 ;; frame into another gets into our way.  `last-x' and `last-y'
-	 ;; records the x- and y-coordinates of the previously sampled
-	 ;; position.  The differences between `last-x' and `pos-x' as
-	 ;; well as `last-y' and `pos-y' determine the amount the mouse
-	 ;; has been dragged between the last two samples.
-         pos-x-y pos-x pos-y
-         (last-x-y (mouse-absolute-pixel-position))
-         (last-x (car last-x-y))
-         (last-y (cdr last-x-y))
-         ;; `snap-x' and `snap-y' record the x- and y-coordinates of the
+	 ;; Initial "first" mouse position.  While dragging we base all
+	 ;; calculations against that position.
+	 (first-x-y (mouse-absolute-pixel-position))
+         (first-x (car first-x-y))
+         (first-y (cdr first-x-y))
+         ;; `snap-width' (maybe also a yet to be provided `snap-height')
+         ;; could become floats to handle proportionality wrt PARENT.
+         ;; We don't do any checks on this parameter so far.
+         (snap-width (frame-parameter frame 'snap-width))
+	 ;; `snap-x' and `snap-y' record the x- and y-coordinates of the
          ;; mouse position when FRAME snapped.  As soon as the
          ;; difference between `pos-x' and `snap-x' (or `pos-y' and
          ;; `snap-y') exceeds the value of FRAME's `snap-width'
@@ -678,176 +767,144 @@ mouse-drag-frame
           (lambda (event)
             (interactive "e")
             (when (consp event)
-              (setq pos-x-y (mouse-absolute-pixel-position))
-              (setq pos-x (car pos-x-y))
-              (setq pos-y (cdr pos-x-y))
-              (cond
-               ((eq part 'left)
-                (mouse-resize-frame frame (- last-x pos-x) 0 t))
-               ((eq part 'top)
-                (mouse-resize-frame frame 0 (- last-y pos-y) nil t))
-               ((eq part 'right)
-                (mouse-resize-frame frame (- pos-x last-x) 0))
-               ((eq part 'bottom)
-                (mouse-resize-frame frame 0 (- pos-y last-y)))
-               ((eq part 'top-left)
-                (mouse-resize-frame
-                 frame (- last-x pos-x) (- last-y pos-y) t t))
-               ((eq part 'top-right)
-                (mouse-resize-frame
-                 frame (- pos-x last-x) (- last-y pos-y) nil t))
-               ((eq part 'bottom-left)
-                (mouse-resize-frame
-                 frame (- last-x pos-x) (- pos-y last-y) t))
-               ((eq part 'bottom-right)
-                (mouse-resize-frame
-                 frame (- pos-x last-x) (- pos-y last-y)))
-               ((eq part 'move)
-                (let* ((old-position (frame-position frame))
-                       (old-left (car old-position))
-                       (old-top (cdr old-position))
-                       (left (+ old-left (- pos-x last-x)))
-                       (top (+ old-top (- pos-y last-y)))
-                       right bottom
-                       ;; `snap-width' (maybe also a yet to be provided
-                       ;; `snap-height') could become floats to handle
-                       ;; proportionality wrt PARENT.  We don't do any
-                       ;; checks on this parameter so far.
-                       (snap-width (frame-parameter frame 'snap-width)))
-                  ;; Docking and constraining.
-                  (when (and (numberp snap-width) parent-edges)
+              (let* ((last-x-y (mouse-absolute-pixel-position))
+		     (last-x (car last-x-y))
+		     (last-y (cdr last-x-y))
+		     (left (- last-x first-x))
+		     (top (- last-y first-y))
+                     right bottom)
+		(setq left (+ first-left left))
+		(setq top (+ first-top top))
+                ;; Docking and constraining.
+                (when (and (numberp snap-width) parent-edges)
+                  (cond
+                   ;; Docking at the left parent edge.
+                   ((< last-x first-x)
                     (cond
-                     ;; Docking at the left parent edge.
-                     ((< pos-x last-x)
-                      (cond
-                       ((and (> left parent-left)
-                             (<= (- left parent-left) snap-width))
-                        ;; Snap when the mouse moved leftward and
-                        ;; FRAME's left edge would end up within
-                        ;; `snap-width' pixels from PARENT's left edge.
-                        (setq snap-x pos-x)
-                        (setq left parent-left))
-                       ((and (<= left parent-left)
-                             (<= (- parent-left left) snap-width)
-                             snap-x (<= (- snap-x pos-x) snap-width))
-                        ;; Stay snapped when the mouse moved leftward
-                        ;; but not more than `snap-width' pixels from
-                        ;; the time FRAME snapped.
-                        (setq left parent-left))
-                       (t
-                        ;; Unsnap when the mouse moved more than
-                        ;; `snap-width' pixels leftward from the time
-                        ;; FRAME snapped.
-                        (setq snap-x nil))))
-                     ((> pos-x last-x)
-                      (setq right (+ left width))
-                      (cond
-                       ((and (< right parent-right)
-                             (<= (- parent-right right) snap-width))
-                        ;; Snap when the mouse moved rightward and
-                        ;; FRAME's right edge would end up within
-                        ;; `snap-width' pixels from PARENT's right edge.
-                        (setq snap-x pos-x)
-                        (setq left (- parent-right width)))
-                       ((and (>= right parent-right)
-                             (<= (- right parent-right) snap-width)
-                             snap-x (<= (- pos-x snap-x) snap-width))
-                        ;; Stay snapped when the mouse moved rightward
-                        ;; but not more more than `snap-width' pixels
-                        ;; from the time FRAME snapped.
-                        (setq left (- parent-right width)))
-                       (t
-                        ;; Unsnap when the mouse moved rightward more
-                        ;; than `snap-width' pixels from the time FRAME
-                        ;; snapped.
-                        (setq snap-x nil)))))
-
+                     ((and (> left parent-left)
+                           (<= (- left parent-left) snap-width))
+                      ;; Snap when the mouse moved leftward and FRAME's
+                      ;; left edge would end up within `snap-width'
+                      ;; pixels from PARENT's left edge.
+                      (setq snap-x last-x)
+                      (setq left parent-left))
+                     ((and (<= left parent-left)
+                           (<= (- parent-left left) snap-width)
+                           snap-x (<= (- snap-x last-x) snap-width))
+                      ;; Stay snapped when the mouse moved leftward but
+                      ;; not more than `snap-width' pixels from the time
+                      ;; FRAME snapped.
+                      (setq left parent-left))
+                     (t
+                      ;; Unsnap when the mouse moved more than
+                      ;; `snap-width' pixels leftward from the time
+                      ;; FRAME snapped.
+                      (setq snap-x nil))))
+                   ((> last-x first-x)
+                    (setq right (+ left native-width))
                     (cond
-                     ((< pos-y last-y)
-                      (cond
-                       ((and (> top parent-top)
-                             (<= (- top parent-top) snap-width))
-                        ;; Snap when the mouse moved upward and FRAME's
-                        ;; top edge would end up within `snap-width'
-                        ;; pixels from PARENT's top edge.
-                        (setq snap-y pos-y)
-                        (setq top parent-top))
-                       ((and (<= top parent-top)
-                             (<= (- parent-top top) snap-width)
-                             snap-y (<= (- snap-y pos-y) snap-width))
-                        ;; Stay snapped when the mouse moved upward but
-                        ;; not more more than `snap-width' pixels from
-                        ;; the time FRAME snapped.
-                        (setq top parent-top))
-                       (t
-                        ;; Unsnap when the mouse moved upward more than
-                        ;; `snap-width' pixels from the time FRAME
-                        ;; snapped.
-                        (setq snap-y nil))))
-                     ((> pos-y last-y)
-                      (setq bottom (+ top height))
-                      (cond
-                       ((and (< bottom parent-bottom)
-                             (<= (- parent-bottom bottom) snap-width))
-                        ;; Snap when the mouse moved downward and
-                        ;; FRAME's bottom edge would end up within
-                        ;; `snap-width' pixels from PARENT's bottom
-                        ;; edge.
-                        (setq snap-y pos-y)
-                        (setq top (- parent-bottom height)))
-                       ((and (>= bottom parent-bottom)
-                             (<= (- bottom parent-bottom) snap-width)
-                             snap-y (<= (- pos-y snap-y) snap-width))
-                        ;; Stay snapped when the mouse moved downward
-                        ;; but not more more than `snap-width' pixels
-                        ;; from the time FRAME snapped.
-                        (setq top (- parent-bottom height)))
-                       (t
-                        ;; Unsnap when the mouse moved downward more
-                        ;; than `snap-width' pixels from the time FRAME
-                        ;; snapped.
-                        (setq snap-y nil))))))
-
-                  ;; If requested, constrain FRAME's draggable areas to
-                  ;; PARENT's edges.  The `top-visible' parameter should
-                  ;; be set when FRAME has a draggable header-line.  If
-                  ;; set to a number, it ascertains that the top of
-                  ;; FRAME is always constrained to the top of PARENT
-                  ;; and that at least as many pixels of FRAME as
-                  ;; specified by that number are visible on each of the
-                  ;; three remaining sides of PARENT.
-                  ;;
-                  ;; The `bottom-visible' parameter should be set when
-                  ;; FRAME has a draggable mode-line.  If set to a
-                  ;; number, it ascertains that the bottom of FRAME is
-                  ;; always constrained to the bottom of PARENT and that
-                  ;; at least as many pixels of FRAME as specified by
-                  ;; that number are visible on each of the three
-                  ;; remaining sides of PARENT.
-                  (let ((par (frame-parameter frame 'top-visible))
-                        bottom-visible)
-                    (unless par
-                      (setq par (frame-parameter frame 'bottom-visible))
-                      (setq bottom-visible t))
-                    (when (and (numberp par) parent-edges)
-                      (setq left
-                            (max (min (- parent-right par) left)
-                                 (+ (- parent-left width) par)))
-                      (setq top
-                            (if bottom-visible
-                                (min (max top (- parent-top (- height par)))
-                                     (- parent-bottom height))
-                              (min (max top parent-top)
-                                   (- parent-bottom par))))))
-
-                  ;; Use `modify-frame-parameters' since `left' and
-                  ;; `top' may want to move FRAME out of its PARENT.
-                  (modify-frame-parameters
-                   frame
-                   `((left . (+ ,left)) (top . (+ ,top)))))))
-              (setq last-x pos-x)
-              (setq last-y pos-y))))
-         (old-track-mouse track-mouse))
+                     ((and (< right parent-right)
+                           (<= (- parent-right right) snap-width))
+                      ;; Snap when the mouse moved rightward and FRAME's
+                      ;; right edge would end up within `snap-width'
+                      ;; pixels from PARENT's right edge.
+                      (setq snap-x last-x)
+                      (setq left (- parent-right native-width)))
+                     ((and (>= right parent-right)
+                           (<= (- right parent-right) snap-width)
+                           snap-x (<= (- last-x snap-x) snap-width))
+                      ;; Stay snapped when the mouse moved rightward but
+                      ;; not more more than `snap-width' pixels from the
+                      ;; time FRAME snapped.
+                      (setq left (- parent-right native-width)))
+                     (t
+                      ;; Unsnap when the mouse moved rightward more than
+                      ;; `snap-width' pixels from the time FRAME
+                      ;; snapped.
+                      (setq snap-x nil)))))
+                  (cond
+                   ((< last-y first-y)
+                    (cond
+                     ((and (> top parent-top)
+                           (<= (- top parent-top) snap-width))
+                      ;; Snap when the mouse moved upward and FRAME's
+                      ;; top edge would end up within `snap-width'
+                      ;; pixels from PARENT's top edge.
+                      (setq snap-y last-y)
+                      (setq top parent-top))
+                     ((and (<= top parent-top)
+                           (<= (- parent-top top) snap-width)
+                           snap-y (<= (- snap-y last-y) snap-width))
+                      ;; Stay snapped when the mouse moved upward but
+                      ;; not more more than `snap-width' pixels from the
+                      ;; time FRAME snapped.
+                      (setq top parent-top))
+                     (t
+                      ;; Unsnap when the mouse moved upward more than
+                      ;; `snap-width' pixels from the time FRAME
+                      ;; snapped.
+                      (setq snap-y nil))))
+                   ((> last-y first-y)
+                    (setq bottom (+ top native-height))
+                    (cond
+                     ((and (< bottom parent-bottom)
+                           (<= (- parent-bottom bottom) snap-width))
+                      ;; Snap when the mouse moved downward and FRAME's
+                      ;; bottom edge would end up within `snap-width'
+                      ;; pixels from PARENT's bottom edge.
+                      (setq snap-y last-y)
+                      (setq top (- parent-bottom native-height)))
+                     ((and (>= bottom parent-bottom)
+                           (<= (- bottom parent-bottom) snap-width)
+                           snap-y (<= (- last-y snap-y) snap-width))
+                      ;; Stay snapped when the mouse moved downward but
+                      ;; not more more than `snap-width' pixels from the
+                      ;; time FRAME snapped.
+                      (setq top (- parent-bottom native-height)))
+                     (t
+                      ;; Unsnap when the mouse moved downward more than
+                      ;; `snap-width' pixels from the time FRAME
+                      ;; snapped.
+                      (setq snap-y nil))))))
+
+                ;; If requested, constrain FRAME's draggable areas to
+                ;; PARENT's edges.  The `top-visible' parameter should
+                ;; be set when FRAME has a draggable header-line.  If
+                ;; set to a number, it ascertains that the top of FRAME
+                ;; is always constrained to the top of PARENT and that
+                ;; at least as many pixels of FRAME as specified by that
+                ;; number are visible on each of the three remaining
+                ;; sides of PARENT.
+                ;;
+                ;; The `bottom-visible' parameter should be set when
+                ;; FRAME has a draggable mode-line.  If set to a number,
+                ;; it ascertains that the bottom of FRAME is always
+                ;; constrained to the bottom of PARENT and that at least
+                ;; as many pixels of FRAME as specified by that number
+                ;; are visible on each of the three remaining sides of
+                ;; PARENT.
+                (let ((par (frame-parameter frame 'top-visible))
+                      bottom-visible)
+                  (unless par
+                    (setq par (frame-parameter frame 'bottom-visible))
+                    (setq bottom-visible t))
+                  (when (and (numberp par) parent-edges)
+                    (setq left
+                          (max (min (- parent-right par) left)
+                               (+ (- parent-left native-width) par)))
+                    (setq top
+                          (if bottom-visible
+                              (min (max top (- parent-top (- native-height par)))
+                                   (- parent-bottom native-height))
+                            (min (max top parent-top)
+                                 (- parent-bottom par))))))
+
+                ;; Use `modify-frame-parameters' since `left' and `top'
+                ;; may want to move FRAME out of its PARENT.
+                (modify-frame-parameters
+                 frame
+                 `((left . (+ ,left)) (top . (+ ,top))))))))
+	 (old-track-mouse track-mouse))
     ;; Start tracking.  The special value 'dragging' signals the
     ;; display engine to freeze the mouse pointer shape for as long
     ;; as we drag.
@@ -879,49 +936,49 @@ mouse-drag-left-edge
   "Drag left edge of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'left))
+  (mouse-drag-frame-resize start-event 'left))
 
 (defun mouse-drag-top-left-corner (start-event)
   "Drag top left corner of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'top-left))
+  (mouse-drag-frame-resize start-event 'top-left))
 
 (defun mouse-drag-top-edge (start-event)
   "Drag top edge of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'top))
+  (mouse-drag-frame-resize start-event 'top))
 
 (defun mouse-drag-top-right-corner (start-event)
   "Drag top right corner of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'top-right))
+  (mouse-drag-frame-resize start-event 'top-right))
 
 (defun mouse-drag-right-edge (start-event)
   "Drag right edge of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'right))
+  (mouse-drag-frame-resize start-event 'right))
 
 (defun mouse-drag-bottom-right-corner (start-event)
   "Drag bottom right corner of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'bottom-right))
+  (mouse-drag-frame-resize start-event 'bottom-right))
 
 (defun mouse-drag-bottom-edge (start-event)
   "Drag bottom edge of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'bottom))
+  (mouse-drag-frame-resize start-event 'bottom))
 
 (defun mouse-drag-bottom-left-corner (start-event)
   "Drag bottom left corner of a frame with the mouse.
 START-EVENT is the starting mouse event of the drag action."
   (interactive "e")
-  (mouse-drag-frame start-event 'bottom-left))
+  (mouse-drag-frame-resize start-event 'bottom-left))
 
 (defcustom mouse-select-region-move-to-beginning nil
   "Effect of selecting a region extending backward from double click.
diff --git a/src/dispnew.c b/src/dispnew.c
index 9af1ce259d..2d64d4660a 100644
--- a/src/dispnew.c
+++ b/src/dispnew.c
@@ -5741,7 +5741,13 @@ do_pending_window_change (bool safe)
 	{
 	  struct frame *f = XFRAME (frame);
 
-	  if (f->new_height != 0 || f->new_width != 0)
+	  if (FRAME_PARENT_FRAME (f))
+	    {
+	      if (f->new_height != 0 || f->new_width != 0)
+		change_frame_size (f, f->new_width, f->new_height,
+				   0, 0, safe, f->new_pixelwise);
+	    }
+	  else if (f->new_height != 0 || f->new_width != 0)
 	    change_frame_size (f, f->new_width, f->new_height,
 			       0, 0, safe, f->new_pixelwise);
 	}