Say a frame is split (by C-x 3) into 2 windows that both display the same buffer.
If I enable follow-mode, the left window will always display the content closer to the beginning-of-buffer than the right one.
How to swap these two windows (so that the left window will display the content following what is displayed by the right one)
How my Emacs currently behaves:
emacs-version: 28.2
system-configuration: x86_64-w64-mingw32
To achieve the desired effect you need to change two lines in the source code of 'follow.el' as done below:
(defun follow--window-sorter (w1 w2)
"Sorting function for W1 and W2 based on their positions.
Return non-nil if W1 is above W2; if their top-lines
are at the same position, return non-nil if W1 is to the
left of W2."
(let* ((edge-1 (window-pixel-edges w1))
(edge-2 (window-pixel-edges w2))
(y1 (nth 1 edge-1))
(y2 (nth 1 edge-2)))
(if (= y1 y2)
;; (< (car edge-1) (car edge-2)) ;; <<<===
(< (car edge-2) (car edge-1))
;; (< y1 y2)))) ;; <<<===
(< y2 y1))))
See how it looks like if changed as above:
Knowing this above feel free to update my answer with code of a function follow-toggle-right-to-left-order toggling a value of follow-right-to-left-order variable used to switch the sorting order in follow--window-sorter.
Below the not yet tested code of a patch with the above mentioned functionality:
(setq follow-right-to-left-order nil)
(defun follow-toggle-right-to-left-order ()
"toggle value used by (defun follow--window-sorter ..."
(= follow-right-to-left-order t
(setq follow-right-to-left-order nil)
(setq follow-right-to-left-order t)
)
)
(defun follow--window-sorter (w1 w2)
"Sorting function for W1 and W2 based on their positions.
Return non-nil if W1 is above W2; if their top-lines
are at the same position, return non-nil if W1 is to the
left of W2."
(let* ((edge-1 (window-pixel-edges w1))
(edge-2 (window-pixel-edges w2))
(y1 (nth 1 edge-1))
(y2 (nth 1 edge-2))))
(if (= y1 y2)
(if follow-right-to-left-order
(< (car edge-2) (car edge-1))
(< (car edge-1) (car edge-2))
))
(if follow-right-to-left-order
(< y2 y1)
(< y1 y2)
)
)
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;; May the Code be with You!
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