--- /dev/null
+;;; ruler-mode.el --- Display a ruler in the header line
+
+;; Copyright (C) 2001 Free Software Foundation, Inc.
+
+;; Author: David Ponce <david@dponce.com>
+;; Maintainer: David Ponce <david@dponce.com>
+;; Created: 24 Mar 2001
+;; Version: 1.3.1
+;; Keywords: environment
+
+;; 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', `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' to the ruler
+;; graduation where the mouse pointer is on.
+;;
+;; [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 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-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 '<major-mode>-hook 'ruler-mode)
+;;
+
+;;; History:
+;;
+
+;;; Code:
+(eval-when-compile
+ (require 'wid-edit))
+
+(defgroup ruler-mode nil
+ "Display a ruler in the header line."
+ :version "21.2"
+ :group 'environment)
+
+(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
+<C-down-mouse-1> and <C-down-mouse-3> on the ruler to respectively add
+or remove a tab stop. \\[ruler-mode-toggle-show-tab-stops] or
+<C-down-mouse-2> 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-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)))
+
+(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-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)))))
+
+(defun ruler-mode-mouse-set-fill-column (start-event)
+ "Set `fill-column' 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 rm hs fc)
+ (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)
+ fc (+ col hs))
+ (and (>= col 0) (< (+ col lm rm) w)
+ (progn
+ (message "Fill column set to %d (was %d)" fc fill-column)
+ (setq fill-column fc)))))))
+
+(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)
+ (when ruler-mode
+ (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-set-fill-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.
+ (setq ruler-mode-header-line-format-old header-line-format
+ 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.
+ (if (eq header-line-format ruler-mode-header-line-format)
+ (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 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 fill col, \
+C-mouse-2: show tabs"
+ "Help string shown when mouse pointer is over the ruler.
+`ruler-mode-show-tab-stops' is nil.")
+
+(defconst ruler-mode-ruler-help-echo-tab
+ "\
+C-mouse1/3: set/unset tab, \
+C-mouse-2: hide tabs"
+ "Help string shown when mouse pointer is over the ruler.
+`ruler-mode-show-tab-stops' is non-nil.")
+
+(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.")
+
+(defvar ruler-mode-left-fringe-cols nil
+ "Hold last result of function `ruler-mode-left-fringe-cols'.
+This cache is local to each frame.")
+(make-variable-frame-local 'ruler-mode-left-fringe-cols)
+
+(defun ruler-mode-left-fringe-cols (&optional check)
+ "Return the character width of fringe and left vertical scrollbar.
+That is a pair (FRINGE-COLS . VSCROLLBAR-COLS) where:
+
+- - FRINGE-COLS is the number of columns occupied by a fringe area.
+
+- - VSCROLLBAR-COLS is the number of columns occupied by the left
+ vertical scrollbar or 0 if there is no vertical scrollbar on the
+ left side.
+
+The first time this function is called its result is saved in a frame
+local cache and then returned on next calls. If optional argument
+CHECK is non-nil or if the frame 'vertical-scroll-bars parameter has
+been changed the function re-computes the result."
+ (let* ((f (selected-frame))
+ (vsb (frame-parameter f 'vertical-scroll-bars))
+ (lfc (frame-parameter f 'ruler-mode-left-fringe-cols)))
+ (if (or check (not (eq (cdr lfc) vsb)))
+ (let* ((w (frame-first-window f))
+ (sbw (frame-pixel-width f))
+ (chw (frame-char-width f))
+ (chx (/ 1.0 (float chw)))
+ (pos (cons 0.0 0))
+ (lfw 0.0)
+ coord)
+ (if vsb
+ (modify-frame-parameters
+ f '((vertical-scroll-bars . nil))))
+ (setq coord (coordinates-in-window-p pos w))
+ (while (not (memq coord '(left-fringe mode-line)))
+ (setcdr pos (1+ (cdr pos)))
+ (setq coord (coordinates-in-window-p pos w)))
+ (while (eq coord 'left-fringe)
+ (setcar pos (+ (car pos) chx))
+ (setq lfw (+ lfw chx)
+ coord (coordinates-in-window-p pos w)))
+ (or vsb
+ (modify-frame-parameters
+ f '((vertical-scroll-bars . right))))
+ (setq sbw (/ (abs (- sbw (frame-pixel-width f))) chw)
+ lfw (floor lfw))
+ (setq lfc (cons (cons lfw (if (eq vsb 'left) sbw 0)) vsb))
+ (modify-frame-parameters
+ f (list (cons 'vertical-scroll-bars vsb)
+ (cons 'ruler-mode-left-fringe-cols lfc)))))
+ (car lfc)))
+
+(defun ruler-mode-ruler ()
+ "Return a string ruler."
+ (if ruler-mode
+ (let* ((lfr (ruler-mode-left-fringe-cols))
+ (w (+ (window-width) 1 (cdr lfr)))
+ (m (window-margins))
+ (l (or (car m) 0))
+ (r (or (cdr m) 0))
+ (j (+ (car lfr) (cdr lfr)))
+ (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 j ?\ )))
+ 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-tab
+ 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 `fill-column' marker.
+ (setq i (- fill-column o))
+ (and (>= i 0) (< i r)
+ (aset ruler i ruler-mode-fill-column-char)
+ (put-text-property
+ i (1+ i) 'face 'ruler-mode-fill-column-face
+ 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 fill-column face
+ ((eq ts fill-column)
+ 'ruler-mode-fill-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
HCoop / bpt / emacs.git / commitdiff