;;; ruler-mode.el --- display a ruler in the header line ;; Copyright (C) 2001, 2002, 2003 Free Software Foundation, Inc. ;; Author: David Ponce ;; Maintainer: David Ponce ;; Created: 24 Mar 2001 ;; Version: 1.5 ;; Keywords: convenience ;; This file is part of GNU Emacs. ;; This program is free software; you can redistribute it and/or ;; modify it under the terms of the GNU General Public License as ;; published by the Free Software Foundation; either version 2, or (at ;; your option) any later version. ;; This program is distributed in the hope that it will be useful, but ;; WITHOUT ANY WARRANTY; without even the implied warranty of ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU ;; General Public License for more details. ;; You should have received a copy of the GNU General Public License ;; along with this program; see the file COPYING. If not, write to ;; the Free Software Foundation, Inc., 59 Temple Place - Suite 330, ;; Boston, MA 02111-1307, USA. ;;; Commentary: ;; This library provides a minor mode to display a ruler in the header ;; line. It works only on Emacs 21. ;; ;; You can use the mouse to change the `fill-column' `comment-column', ;; `goal-column', `window-margins' and `tab-stop-list' settings: ;; ;; [header-line (shift down-mouse-1)] set left margin to the ruler ;; graduation where the mouse pointer is on. ;; ;; [header-line (shift down-mouse-3)] set right margin to the ruler ;; graduation where the mouse pointer is on. ;; ;; [header-line down-mouse-2] set `fill-column', `comment-column' or ;; `goal-column' to the ruler graduation with the mouse dragging. ;; ;; [header-line (control down-mouse-1)] add a tab stop to the ruler ;; graduation where the mouse pointer is on. ;; ;; [header-line (control down-mouse-3)] remove the tab stop at the ;; ruler graduation where the mouse pointer is on. ;; ;; [header-line (control down-mouse-2)] or M-x ;; `ruler-mode-toggle-show-tab-stops' toggle showing and visually ;; editing `tab-stop-list' setting. The `ruler-mode-show-tab-stops' ;; option controls if the ruler shows tab stops by default. ;; ;; In the ruler the character `ruler-mode-current-column-char' shows ;; the `current-column' location, `ruler-mode-fill-column-char' shows ;; the `fill-column' location, `ruler-mode-comment-column-char' shows ;; the `comment-column' location, `ruler-mode-goal-column-char' shows ;; the `goal-column' and `ruler-mode-tab-stop-char' shows tab ;; stop locations. `window-margins' areas are shown with a different ;; background color. ;; ;; It is also possible to customize the following characters: ;; ;; - `ruler-mode-margins-char' character used to pad margin areas ;; (space by default). ;; - `ruler-mode-basic-graduation-char' character used for basic ;; graduations ('.' by default). ;; - `ruler-mode-inter-graduation-char' character used for ;; intermediate graduations ('!' by default). ;; ;; The following faces are customizable: ;; ;; - `ruler-mode-default-face' the ruler default face. ;; - `ruler-mode-fill-column-face' the face used to highlight the ;; `fill-column' character. ;; - `ruler-mode-comment-column-face' the face used to highlight the ;; `comment-column' character. ;; - `ruler-mode-goal-column-face' the face used to highlight the ;; `goal-column' character. ;; - `ruler-mode-current-column-face' the face used to highlight the ;; `current-column' character. ;; - `ruler-mode-tab-stop-face' the face used to highlight tab stop ;; characters. ;; - `ruler-mode-margins-face' the face used to highlight the ;; `window-margins' areas. ;; - `ruler-mode-column-number-face' the face used to highlight the ;; number graduations. ;; ;; `ruler-mode-default-face' inherits from the built-in `default' face. ;; All `ruler-mode' faces inerit from `ruler-mode-default-face'. ;; ;; WARNING: To keep ruler graduations aligned on text columns it is ;; important to use the same font family and size for ruler and text ;; areas. ;; Installation ;; ;; To automatically display the ruler in specific major modes use: ;; ;; (add-hook '-hook 'ruler-mode) ;; ;;; History: ;; ;;; Code: (eval-when-compile (require 'wid-edit)) (defgroup ruler-mode nil "Display a ruler in the header line." :version "21.4" :group 'convenience) (defcustom ruler-mode-show-tab-stops nil "*If non-nil the ruler shows tab stop positions. Also allowing to visually change `tab-stop-list' setting using and on the ruler to respectively add or remove a tab stop. \\[ruler-mode-toggle-show-tab-stops] or on the ruler toggles showing/editing of tab stops." :group 'ruler-mode :type 'boolean) ;; IMPORTANT: This function must be defined before the following ;; defcustoms because it is used in their :validate clause. (defun ruler-mode-character-validate (widget) "Ensure WIDGET value is a valid character value." (save-excursion (let ((value (widget-value widget))) (if (char-valid-p value) nil (widget-put widget :error (format "Invalid character value: %S" value)) widget)))) (defcustom ruler-mode-fill-column-char (if window-system ?\¶ ?\|) "*Character used at the `fill-column' location." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-comment-column-char ?\# "*Character used at the `comment-column' location." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-goal-column-char ?G "*Character used at the `goal-column' location." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-current-column-char (if window-system ?\¦ ?\@) "*Character used at the `current-column' location." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-tab-stop-char ?\T "*Character used at `tab-stop-list' locations." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-margins-char ?\ "*Character used in margin areas." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-basic-graduation-char ?\. "*Character used for basic graduations." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-inter-graduation-char ?\! "*Character used for intermediate graduations." :group 'ruler-mode :type '(choice (character :tag "Character") (integer :tag "Integer char value" :validate ruler-mode-character-validate))) (defcustom ruler-mode-set-goal-column-ding-flag t "*Non-nil means do `ding' when `goal-column' is set." :group 'ruler-mode :type 'boolean) (defface ruler-mode-default-face '((((type tty)) (:inherit default :background "grey64" :foreground "grey50" )) (t (:inherit default :background "grey76" :foreground "grey64" :box (:color "grey76" :line-width 1 :style released-button) ))) "Default face used by the ruler." :group 'ruler-mode) (defface ruler-mode-column-number-face '((t (:inherit ruler-mode-default-face :foreground "black" ))) "Face used to highlight number graduations." :group 'ruler-mode) (defface ruler-mode-fill-column-face '((t (:inherit ruler-mode-default-face :foreground "red" ))) "Face used to highlight the fill column character." :group 'ruler-mode) (defface ruler-mode-comment-column-face '((t (:inherit ruler-mode-default-face :foreground "red" ))) "Face used to highlight the comment column character." :group 'ruler-mode) (defface ruler-mode-goal-column-face '((t (:inherit ruler-mode-default-face :foreground "red" ))) "Face used to highlight the goal column character." :group 'ruler-mode) (defface ruler-mode-tab-stop-face '((t (:inherit ruler-mode-default-face :foreground "steelblue" ))) "Face used to highlight tab stop characters." :group 'ruler-mode) (defface ruler-mode-margins-face '((((type tty)) (:inherit ruler-mode-default-face :background "grey50" )) (t (:inherit ruler-mode-default-face :background "grey64" ))) "Face used to highlight the `window-margins' areas." :group 'ruler-mode) (defface ruler-mode-current-column-face '((t (:inherit ruler-mode-default-face :weight bold :foreground "yellow" ))) "Face used to highlight the `current-column' character." :group 'ruler-mode) (defun ruler-mode-mouse-set-left-margin (start-event) "Set left margin to the graduation where the mouse pointer is on. START-EVENT is the mouse click event." (interactive "e") (let* ((start (event-start start-event)) (end (event-end start-event)) w col m lm0 lm rm) (if (eq start end) ;; mouse click (save-selected-window (select-window (posn-window start)) (setq m (window-margins) lm0 (or (car m) 0) rm (or (cdr m) 0) w (window-width) col (car (posn-col-row start)) lm (min (- w rm) col)) (message "Left margin set to %d (was %d)" lm lm0) (set-window-margins nil lm rm))))) (defun ruler-mode-mouse-set-right-margin (start-event) "Set right margin to the graduation where the mouse pointer is on. START-EVENT is the mouse click event." (interactive "e") (let* ((start (event-start start-event)) (end (event-end start-event)) m col w lm rm0 rm) (if (eq start end) ;; mouse click (save-selected-window (select-window (posn-window start)) (setq m (window-margins) rm0 (or (cdr m) 0) lm (or (car m) 0) col (car (posn-col-row start)) w (window-width) rm (max 0 (- w col))) (message "Right margin set to %d (was %d)" rm rm0) (set-window-margins nil lm rm))))) (defvar ruler-mode-mouse-current-grab-object nil "Column symbol dragged in the ruler. That is `fill-column', `comment-column', `goal-column', or nil when nothing is dragged.") (defun ruler-mode-mouse-grab-any-column (start-event) "Set a column symbol to the graduation with mouse dragging. See also variable `ruler-mode-mouse-current-grab-object'. START-EVENT is the mouse down event." (interactive "e") (setq ruler-mode-mouse-current-grab-object nil) (let* ((start (event-start start-event)) m col w lm rm hs newc oldc) (save-selected-window (select-window (posn-window start)) (setq m (window-margins) lm (or (car m) 0) rm (or (cdr m) 0) col (- (car (posn-col-row start)) lm) w (window-width) hs (window-hscroll) newc (+ col hs)) ;; ;; About the ways to handle the goal column: ;; A. update the value of the goal column if goal-column has ;; non-nil value and if the mouse is dragged ;; B. set value to the goal column if goal-column has nil and if ;; the mouse is just clicked, not dragged. ;; C. unset value to the goal column if goal-column has non-nil ;; and mouse is just clicked on goal-column character on the ;; ruler, not dragged. ;; (and (>= col 0) (< (+ col lm rm) w) (cond ((eq newc fill-column) (setq oldc fill-column) (setq ruler-mode-mouse-current-grab-object 'fill-column) t) ((eq newc comment-column) (setq oldc comment-column) (setq ruler-mode-mouse-current-grab-object 'comment-column) t) ((eq newc goal-column) ; A. update goal column (setq oldc goal-column) (setq ruler-mode-mouse-current-grab-object 'goal-column) t) ((null goal-column) ; B. set goal column (setq oldc goal-column) (setq goal-column newc) ;; mouse-2 coming AFTER drag-mouse-2 invokes `ding'. ;; This `ding' flushes the next messages about setting ;; goal column. So here I force fetch the event(mouse-2) ;; and throw away. (read-event) ;; Ding BEFORE `message' is OK. (if ruler-mode-set-goal-column-ding-flag (ding)) (message "Goal column %d (click `%s' on the ruler again to unset it)" newc (propertize (char-to-string ruler-mode-goal-column-char) 'face 'ruler-mode-goal-column-face)) ;; don't enter drag iteration nil)) (if (eq 'click (ruler-mode-mouse-drag-any-column-iteration (posn-window start))) (if (eq 'goal-column ruler-mode-mouse-current-grab-object) ;; C. unset goal column (set-goal-column t)) ;; *-column is updated; report it (message "%s is set to %d (was %d)" ruler-mode-mouse-current-grab-object (eval ruler-mode-mouse-current-grab-object) oldc)))))) (defun ruler-mode-mouse-drag-any-column-iteration (window) "Update the ruler while dragging the mouse. WINDOW is the window where the last down-mouse event is occurred. Return a symbol `drag' if the mouse is actually dragged. Return a symbol `click' if the mouse is just clicked." (let (newevent (drag-count 0)) (track-mouse (while (progn (setq newevent (read-event)) (mouse-movement-p newevent)) (setq drag-count (1+ drag-count)) (if (eq window (posn-window (event-end newevent))) (progn (ruler-mode-mouse-drag-any-column newevent) (force-mode-line-update))))) (if (and (eq drag-count 0) (eq 'click (car (event-modifiers newevent)))) 'click 'drag))) (defun ruler-mode-mouse-drag-any-column (start-event) "Update the ruler for START-EVENT, one mouse motion event." (let* ((start (event-start start-event)) (end (event-end start-event)) m col w lm rm hs newc) (save-selected-window (select-window (posn-window start)) (setq m (window-margins) lm (or (car m) 0) rm (or (cdr m) 0) col (- (car (posn-col-row end)) lm) w (window-width) hs (window-hscroll) newc (+ col hs)) (if (and (>= col 0) (< (+ col lm rm) w)) (set ruler-mode-mouse-current-grab-object newc))))) (defun ruler-mode-mouse-add-tab-stop (start-event) "Add a tab stop to the graduation where the mouse pointer is on. START-EVENT is the mouse click event." (interactive "e") (if ruler-mode-show-tab-stops (let* ((start (event-start start-event)) (end (event-end start-event)) m col w lm rm hs ts) (if (eq start end) ;; mouse click (save-selected-window (select-window (posn-window start)) (setq m (window-margins) lm (or (car m) 0) rm (or (cdr m) 0) col (- (car (posn-col-row start)) lm) w (window-width) hs (window-hscroll) ts (+ col hs)) (and (>= col 0) (< (+ col lm rm) w) (not (member ts tab-stop-list)) (progn (message "Tab stop set to %d" ts) (setq tab-stop-list (sort (cons ts tab-stop-list) #'<))))))))) (defun ruler-mode-mouse-del-tab-stop (start-event) "Delete tab stop at the graduation where the mouse pointer is on. START-EVENT is the mouse click event." (interactive "e") (if ruler-mode-show-tab-stops (let* ((start (event-start start-event)) (end (event-end start-event)) m col w lm rm hs ts) (if (eq start end) ;; mouse click (save-selected-window (select-window (posn-window start)) (setq m (window-margins) lm (or (car m) 0) rm (or (cdr m) 0) col (- (car (posn-col-row start)) lm) w (window-width) hs (window-hscroll) ts (+ col hs)) (and (>= col 0) (< (+ col lm rm) w) (member ts tab-stop-list) (progn (message "Tab stop at %d deleted" ts) (setq tab-stop-list (delete ts tab-stop-list))))))))) (defun ruler-mode-toggle-show-tab-stops () "Toggle showing of tab stops on the ruler." (interactive) (setq ruler-mode-show-tab-stops (not ruler-mode-show-tab-stops)) (force-mode-line-update)) (defvar ruler-mode-map (let ((km (make-sparse-keymap))) (define-key km [header-line down-mouse-1] #'ignore) (define-key km [header-line down-mouse-3] #'ignore) (define-key km [header-line down-mouse-2] #'ruler-mode-mouse-grab-any-column) (define-key km [header-line (shift down-mouse-1)] #'ruler-mode-mouse-set-left-margin) (define-key km [header-line (shift down-mouse-3)] #'ruler-mode-mouse-set-right-margin) (define-key km [header-line (control down-mouse-1)] #'ruler-mode-mouse-add-tab-stop) (define-key km [header-line (control down-mouse-3)] #'ruler-mode-mouse-del-tab-stop) (define-key km [header-line (control down-mouse-2)] #'ruler-mode-toggle-show-tab-stops) km) "Keymap for ruler minor mode.") (defvar ruler-mode-header-line-format-old nil "Hold previous value of `header-line-format'.") (make-variable-buffer-local 'ruler-mode-header-line-format-old) (defconst ruler-mode-header-line-format '(:eval (ruler-mode-ruler)) "`header-line-format' used in ruler mode.") ;;;###autoload (define-minor-mode ruler-mode "Display a ruler in the header line if ARG > 0." nil nil ruler-mode-map :group 'ruler-mode (if ruler-mode (progn ;; When `ruler-mode' is on save previous header line format ;; and install the ruler header line format. (when (local-variable-p 'header-line-format) (setq ruler-mode-header-line-format-old header-line-format)) (setq header-line-format ruler-mode-header-line-format) (add-hook 'post-command-hook ; add local hook #'force-mode-line-update nil t)) ;; When `ruler-mode' is off restore previous header line format if ;; the current one is the ruler header line format. (when (eq header-line-format ruler-mode-header-line-format) (kill-local-variable 'header-line-format) (when ruler-mode-header-line-format-old (setq header-line-format ruler-mode-header-line-format-old))) (remove-hook 'post-command-hook ; remove local hook #'force-mode-line-update t))) ;; Add ruler-mode to the minor mode menu in the mode line (define-key mode-line-mode-menu [ruler-mode] `(menu-item "Ruler" ruler-mode :button (:toggle . ruler-mode))) (defconst ruler-mode-ruler-help-echo "\ S-mouse-1/3: set L/R margin, \ mouse-2: set goal column, \ C-mouse-2: show tabs" "Help string shown when mouse is over the ruler. `ruler-mode-show-tab-stops' is nil.") (defconst ruler-mode-ruler-help-echo-when-goal-column "\ S-mouse-1/3: set L/R margin, \ C-mouse-2: show tabs" "Help string shown when mouse is over the ruler. `goal-column' is set and `ruler-mode-show-tab-stops' is nil.") (defconst ruler-mode-ruler-help-echo-when-tab-stops "\ C-mouse1/3: set/unset tab, \ C-mouse-2: hide tabs" "Help string shown when mouse is over the ruler. `ruler-mode-show-tab-stops' is non-nil.") (defconst ruler-mode-fill-column-help-echo "drag-mouse-2: set fill column" "Help string shown when mouse is on the fill column character.") (defconst ruler-mode-comment-column-help-echo "drag-mouse-2: set comment column" "Help string shown when mouse is on the comment column character.") (defconst ruler-mode-goal-column-help-echo "\ drag-mouse-2: set goal column, \ mouse-2: unset goal column" "Help string shown when mouse is on the goal column character.") (defconst ruler-mode-left-margin-help-echo "Left margin %S" "Help string shown when mouse is over the left margin area.") (defconst ruler-mode-right-margin-help-echo "Right margin %S" "Help string shown when mouse is over the right margin area.") (defmacro ruler-mode-left-fringe-cols () "Return the width, measured in columns, of the left fringe area." '(round (or (frame-parameter nil 'left-fringe) 0) (frame-char-width))) (defmacro ruler-mode-right-fringe-cols () "Return the width, measured in columns, of the right fringe area." '(round (or (frame-parameter nil 'right-fringe) 0) (frame-char-width))) (defmacro ruler-mode-left-scroll-bar-cols () "Return the width, measured in columns, of the left vertical scrollbar." '(if (eq (frame-parameter nil 'vertical-scroll-bars) 'left) (let ((sbw (frame-parameter nil 'scroll-bar-width))) ;; nil means it's a non-toolkit scroll bar, ;; and its width in columns is 14 pixels rounded up. (unless sbw (setq sbw 14)) ;; Always round up to multiple of columns. (ceiling sbw (frame-char-width))) 0)) (defmacro ruler-mode-right-scroll-bar-cols () "Return the width, measured in columns, of the right vertical scrollbar." '(if (eq (frame-parameter nil 'vertical-scroll-bars) 'right) (round (or (frame-parameter nil 'scroll-bar-width) 0) (frame-char-width)) 0)) (defun ruler-mode-ruler () "Return a string ruler." (if ruler-mode (let* ((j (+ (ruler-mode-left-fringe-cols) (ruler-mode-left-scroll-bar-cols))) (w (+ (window-width) j)) (m (window-margins)) (l (or (car m) 0)) (r (or (cdr m) 0)) (o (- (window-hscroll) l j)) (i 0) (ruler (concat ;; unit graduations (make-string w ruler-mode-basic-graduation-char) ;; extra space to fill the header line (make-string (+ (ruler-mode-right-fringe-cols) (ruler-mode-right-scroll-bar-cols)) ?\ ))) c k) ;; Setup default face and help echo. (put-text-property 0 (length ruler) 'face 'ruler-mode-default-face ruler) (put-text-property 0 (length ruler) 'help-echo (if ruler-mode-show-tab-stops ruler-mode-ruler-help-echo-when-tab-stops (if goal-column ruler-mode-ruler-help-echo-when-goal-column ruler-mode-ruler-help-echo)) ruler) ;; Setup the local map. (put-text-property 0 (length ruler) 'local-map ruler-mode-map ruler) (setq j (+ l j)) ;; Setup the left margin area. (put-text-property i j 'face 'ruler-mode-margins-face ruler) (put-text-property i j 'help-echo (format ruler-mode-left-margin-help-echo l) ruler) (while (< i j) (aset ruler i ruler-mode-margins-char) (setq i (1+ i))) ;; Setup the ruler area. (setq r (- w r)) (while (< i r) (setq j (+ i o)) (cond ((= (mod j 10) 0) (setq c (number-to-string (/ j 10)) m (length c) k i) (put-text-property i (1+ i) 'face 'ruler-mode-column-number-face ruler) (while (and (> m 0) (>= k 0)) (aset ruler k (aref c (setq m (1- m)))) (setq k (1- k))) ) ((= (mod j 5) 0) (aset ruler i ruler-mode-inter-graduation-char) ) ) (setq i (1+ i))) ;; Setup the right margin area. (put-text-property i (length ruler) 'face 'ruler-mode-margins-face ruler) (put-text-property i (length ruler) 'help-echo (format ruler-mode-right-margin-help-echo (- w r)) ruler) (while (< i (length ruler)) (aset ruler i ruler-mode-margins-char) (setq i (1+ i))) ;; Show the `goal-column' marker. (if goal-column (progn (setq i (- goal-column o)) (and (>= i 0) (< i r) (aset ruler i ruler-mode-goal-column-char) (progn (put-text-property i (1+ i) 'face 'ruler-mode-goal-column-face ruler) (put-text-property i (1+ i) 'help-echo ruler-mode-goal-column-help-echo ruler)) ))) ;; Show the `comment-column' marker. (setq i (- comment-column o)) (and (>= i 0) (< i r) (aset ruler i ruler-mode-comment-column-char) (progn (put-text-property i (1+ i) 'face 'ruler-mode-comment-column-face ruler) (put-text-property i (1+ i) 'help-echo ruler-mode-comment-column-help-echo ruler))) ;; Show the `fill-column' marker. (setq i (- fill-column o)) (and (>= i 0) (< i r) (aset ruler i ruler-mode-fill-column-char) (progn (put-text-property i (1+ i) 'face 'ruler-mode-fill-column-face ruler) (put-text-property i (1+ i) 'help-echo ruler-mode-fill-column-help-echo ruler))) ;; Show the `tab-stop-list' markers. (if ruler-mode-show-tab-stops (let ((tsl tab-stop-list) ts) (while tsl (setq ts (car tsl) tsl (cdr tsl) i (- ts o)) (and (>= i 0) (< i r) (aset ruler i ruler-mode-tab-stop-char) (put-text-property i (1+ i) 'face (cond ;; Don't override the *-column face ((eq ts fill-column) 'ruler-mode-fill-column-face) ((eq ts comment-column) 'ruler-mode-comment-column-face) ((eq ts goal-column) 'ruler-mode-goal-column-face) (t 'ruler-mode-tab-stop-face)) ruler))))) ;; Show the `current-column' marker. (setq i (- (current-column) o)) (and (>= i 0) (< i r) (aset ruler i ruler-mode-current-column-char) (put-text-property i (1+ i) 'face 'ruler-mode-current-column-face ruler)) ruler))) (provide 'ruler-mode) ;; Local Variables: ;; coding: iso-latin-1 ;; End: ;;; ruler-mode.el ends here