EmacsWiki: crosshairs.el (original) (raw)
;;; crosshairs.el --- Highlight the current line and column.
;;
;; Filename: crosshairs.el
;; Description: Highlight the current line and column.
;; Author: Drew Adams
;; Maintainer: Drew Adams (concat "drew.adams" "@" "oracle" ".com")
;; Copyright (C) 2006-2022, Drew Adams, all rights reserved.
;; Created: Fri Sep 08 13:09:19 2006
;; Version: 0
;; Package-Requires: ((hl-line+ "0") (col-highlight "0") (vline "0"))
;; Last-Updated: Wed Jan 12 12:47:40 2022 (-0800)
;; By: dradams
;; Update #: 519
;; URL: https://www.emacswiki.org/emacs/download/crosshairs.el
;; Doc URL: https://www.emacswiki.org/emacs/CrosshairHighlighting
;; Keywords: faces, frames, emulation, highlight, cursor, accessibility
;; Compatibility: GNU Emacs: 22.x, 23.x, 24.x, 25.x, 26.x
;;
;; Features that might be required by this library:
;;
;; backquote', bytecomp', cconv', cl-lib', col-highlight', ;; hl-line', hl-line+', macroexp', vline'. ;; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; ;;; Commentary: ;; ;; This library highlights the current line and the current column. ;; It combines the features of libraries hl-line.el', hl-line+.el', ;; and col-highlight.el', which let you highlight the line or column
;; individually. See those libraries for more information, in
;; particular for user options that affect the behavior.
;;
;; If you want the horizontal and vertical highlighting to look the
;; same, then:
;;
;; 1. Set option col-highlight-vline-face-flag' to non-nil. ;; 2. Customize faces col-highlight' and hl-line' to look the same. ;; ;; Command crosshairs-mode' toggles this highlighting on and off.
;; You can do this twice in succession to flash the crosshairs to
;; show you where the cursor is. An alternative way to
;; flash-highlight is to use command flash-crosshairs' (once). ;; ;; Command crosshairs-highlight' shows crosshairs highlighting until
;; your next action (next command, technically). Command
;; crosshairs-unhighlight' turns off crosshairs highlighting due to ;; crosshairs-highlight'.
;;
;; With no prefix arg, command crosshairs' is ;; crosshairs-highlight'. With a prefix arg, it is
;; crosshairs-mode'. ;; ;; You can also have crosshairs highlighting come on automatically, ;; when Emacs is idle. Command toggle-crosshairs-when-idle' toggles
;; this mode.
;;
;; You can use command flash-crosshairs' to do what its name says ;; when you switch buffers or windows. Here is how one user did it ;; (rejoin the split URL): ;; https://unix.stackexchange.com/questions/83167/emacs-finding-the- ;; cursor-in-multiple-windows ;; ;; ;; See also: ;; ;; * Library hl-line+.el', which highlights the current line.
;;
;; * Library col-highlight.el', which highlights the current column. ;; ;; * Library cursor-chg.el' or library oneonone.el', to change the ;; cursor type when Emacs is idle. ;; ;; ;; User options defined here: ;; ;; crosshairs-mode'.
;;
;; Commands defined here:
;;
;; crosshairs', crosshairs-flash', crosshairs-highlight', ;; crosshairs-mode', crosshairs-toggle-when-idle', ;; crosshairs-unhighlight', flash-crosshairs', ;; toggle-crosshairs-when-idle'.
;;
;; Internal variables defined here:
;;
;; crosshairs-flash-col-timer', crosshairs-flash-line-timer',
;; `crosshairs-highlight-when-idle-p'.
;;
;; Suggested alternative key bindings:
;;
;; (global-set-key [(control ?+)] 'crosshairs)
;; or (global-set-key [(control ?+)] 'crosshairs-mode)
;; or (global-set-key [(control ?+)] 'crosshairs-flash)
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;;; Change Log:
;;
;; 2022/01/12 dadams
;; Explicitly require hl-line.el and vline.el.
;; 2017/06/26 dadams
;; crosshairs-flash:
;; Use hl-line-unhighlight-now, not global-hl-line-unhighlight, for
;; crosshairs-flash-line-timer. Thx to Dan Harms.
;; 2014/11/28 dadams
;; crosshairs-mode: Call global-hl-line-unhighlight-all (Emacs 24.4+).
;; crosshairs-highlight:
;; Push global-hl-line-overlay to global-hl-line-overlays (Emacs 24.4+).
;; crosshairs-unhighlight: Call global-hl-line-unhighlight-all (Emacs 24.4+).
;; 2014/07/22 dadams
;; Removed extra, vestigial package-requires.
;; 2012/12/25 dadams
;; Added Package-Requires.
;; 2012/05/18 dadams
;; Removed: crosshairs-overlay-priority. Instead, use vline-overlay-priority
;; and col-highlight-overlay-priority.
;; crosshairs-mode, crosshairs-(un)highlight:
;; Do not set the overlay priority - done using defadvice in hl-line+.el and
;; col-highlight.el.
;; 2012/05/17 dadams
;; crosshairs-mode: Made it respect crosshairs-overlay-priority.
;; Removed: crosshairs-vline-same-face-flag.
;; 2011/01/03 dadams
;; Added autoload cookies for defgroup, defcustoms, commands.
;; 2010/06/29 dadams
;; Added: crosshairs-overlay-priority.
;; crosshairs-(un)highlight: Set/remove priority if crosshairs-overlay-priority.
;; 2008/09/03 dadams
;; crosshairs-mode: Don't set previous state if explicit ARG.
;; Added message indicating position.
;; Added: crosshairs, crosshairs-(un)highlight.
;; 2008/08/31 dadams
;; crosshairs-flash: Cancel timers at the outset.
;; Remove hl-line-unhighlight-now from pre-command-hook.
;; 2008/08/08 dadams
;; Added: crosshairs-flash-col-timer, crosshairs-flash-line-timer.
;; crosshairs-flash:
;; Call col-highlight-(un)highlight with arg t.
;; Save unhighlighting timers in crosshairs-flash-(col|line)-timer.
;; First, cancel unhighlighting timers.
;; 2008/01/21 dadams
;; Use vline.el now, instead of column-marker.el.
;; Added group crosshairs, option crosshairs-vline-same-face-flag.
;; crosshairs-mode, crosshairs-toggle-when-idle:
;; If both are already on or off, reflect that as the crosshair state.
;; crosshairs-toggle-when-idle:
;; crosshairs-highlight-when-idle-p, not col-highlight-when-idle-p.
;; crosshairs-flash:
;; Save/restore global-hl-line-mode.
;; Clear and rehighlight column initially. Maybe highlight twice (bug).
;; Don't use highlight modes to unhighlight - just unhighlight.
;; Renamed: line-show-period to hl-line-flash-show-period.
;; Removed semi-support for Emacs 20.
;; 2006/09/08 dadams
;; Created.
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;; 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 3, 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., 51 Franklin Street, Fifth
;; Floor, Boston, MA 02110-1301, USA.
;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;
;;; Code:
(require 'hl-line) ;; Needed by hl-line+.el'. (require 'hl-line+) ;; Requires hl-line.el'.
(require 'vline) ;; Needed by col-highlight.el'. (require 'col-highlight) ;; Requires vline.el'.
(defvar global-hl-line-overlays) ; In `hl-line.el' (Emacs 24.4+)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;;;###autoload
(defgroup crosshairs nil
"Highlight the current line and column."
:prefix "crosshairs-"
:group 'editing :group 'cursor :group 'hl-line :group 'frames
:link (url-link :tag "Send Bug Report" ,(concat "mailto:" "drew.adams" "@" "oracle" ".com?subject=\ crosshairs.el bug: \ &body=Describe bug here, starting with emacs -q'.
Don't forget to mention your Emacs and library versions."))
:link '(url-link :tag "Other Libraries by Drew"
"https://www.emacswiki.org/emacs/DrewsElispLibraries")
:link '(url-link :tag "Download"
"https://www.emacswiki.org/emacs/download/crosshairs.el"))
(defvar crosshairs-highlight-when-idle-p nil "Non-nil means highlight current line and column when Emacs is idle. Do NOT change this yourself; instead, use `\[toggle-crosshairs-when-idle]'.")
(defvar crosshairs-flash-line-timer (timer-create) "Timer used to unhighlight current line for `crosshairs-flash'.")
(defvar crosshairs-flash-col-timer (timer-create) "Timer used to unhighlight current column for `crosshairs-flash'.")
;;;###autoload
(define-minor-mode crosshairs-mode
"Toggle highlighting the current line and column.
With ARG, turn highlighting on if and only if ARG is positive."
:init-value nil :global t :group 'crosshairs
:link (url-link :tag "Send Bug Report" ,(concat "mailto:" "drew.adams" "@" "oracle" ".com?subject=\ crosshairs.el bug: \ &body=Describe bug here, starting with emacs -q'.
Don't forget to mention your Emacs and library versions."))
:link '(url-link :tag "Other Libraries by Drew"
"https://www.emacswiki.org/emacs/DrewsElispLibraries")
:link '(url-link :tag "Download"
"https://www.emacswiki.org/emacs/download/crosshairs.el")
:link '(url-link :tag "Description"
"https://www.emacswiki.org/emacs/ChangingCursorDynamically")
:link '(emacs-commentary-link :tag "Commentary" "crosshairs")
;; If both were already on or off, reflect that as the previous crosshairs state.
(unless arg
(cond ((and global-hl-line-mode column-highlight-mode)
(setq crosshairs-mode nil))
((and (not global-hl-line-mode) (not column-highlight-mode))
(setq crosshairs-mode t))))
(cond (crosshairs-mode
(unless global-hl-line-mode
(global-hl-line-mode 1)
(global-hl-line-highlight))
(column-highlight-mode 1)
(message "Point: %d - Crosshairs mode enabled" (point)))
(t
(global-hl-line-mode -1)
(global-hl-line-unhighlight)
(when (fboundp 'global-hl-line-unhighlight-all) ; Emacs 24.4+
(global-hl-line-unhighlight-all))
(column-highlight-mode -1)
(message "Point: %d - Crosshairs mode disabled" (point)))))
;;;###autoload
(defalias 'toggle-crosshairs-when-idle 'crosshairs-toggle-when-idle)
;;;###autoload
(defun crosshairs-toggle-when-idle (&optional arg)
"Toggle highlighting the current line and column when Emacs is idle.
With prefix argument, turn on if ARG > 0; else turn off.
You can use commands col-highlight-set-interval' and hl-line-when-idle-interval' to change the idle times."
(interactive "P")
;; First, if both are already on or off, reflect that as the crosshair state.
(when (or (and hl-line-when-idle-p col-highlight-when-idle-p)
(and (not hl-line-when-idle-p) (not col-highlight-when-idle-p)))
(setq crosshairs-highlight-when-idle-p hl-line-when-idle-p))
(setq crosshairs-highlight-when-idle-p (if arg
(> (prefix-numeric-value arg) 0)
(not crosshairs-highlight-when-idle-p)))
(setq hl-line-when-idle-p crosshairs-highlight-when-idle-p
col-highlight-when-idle-p crosshairs-highlight-when-idle-p)
(cond (crosshairs-highlight-when-idle-p
(timer-activate-when-idle col-highlight-idle-timer)
(timer-activate-when-idle hl-line-idle-timer)
(add-hook 'pre-command-hook #'col-highlight-unhighlight)
(add-hook 'pre-command-hook #'hl-line-unhighlight-now)
(message "Turned ON highlighting line and column when Emacs is idle."))
(t
(cancel-timer col-highlight-idle-timer)
(cancel-timer hl-line-idle-timer)
(remove-hook 'pre-command-hook #'col-highlight-unhighlight)
(remove-hook 'pre-command-hook #'hl-line-unhighlight-now)
(message "Turned OFF highlighting line and column when Emacs is idle."))))
;;;###autoload
(defalias 'flash-crosshairs 'crosshairs-flash)
;;;###autoload
(defun crosshairs-flash (&optional seconds)
"Highlight the current line and column temporarily.
Highlight the line for hl-line-flash-show-period' and the column for column-show-period' seconds. With prefix argument SECONDS, highlight
both for SECONDS seconds."
(interactive "P")
(cancel-timer crosshairs-flash-line-timer) ; Cancel to prevent duplication.
(cancel-timer crosshairs-flash-col-timer)
(let ((global-hl-line-mode global-hl-line-mode))
(col-highlight-unhighlight t)
(col-highlight-highlight t)
(when column-highlight-mode (col-highlight-highlight t)) ; Extra - a vline bug.
(hl-line-highlight-now)
(remove-hook 'pre-command-hook 'hl-line-unhighlight-now)
(let ((line-period hl-line-flash-show-period) ; Defined in hl-line+.el'. (column-period col-highlight-period)) ; Defined in col-highlight.el'.
(when seconds
(setq line-period (prefix-numeric-value seconds)
column-period line-period))
;; $$$$ Do we need to worry about `global-hl-line-unhighlight-all' here?
(setq crosshairs-flash-line-timer (run-at-time
line-period nil
#'hl-line-unhighlight-now)
crosshairs-flash-col-timer (run-at-time
column-period nil
#'col-highlight-unhighlight t)))))
;;;###autoload (defun crosshairs (&optional modalp) "Highlight current position with crosshairs. With no prefix arg, highlighting turns off at the next command. With a prefix arg, highlighting stays on until you toggle it off using `crosshairs-mode'." (interactive "P") (if modalp (crosshairs-mode 1) (crosshairs-highlight)))
;;;###autoload
(defun crosshairs-highlight (&optional mode nomsg)
"Echo current position and highlight it with crosshairs.
If optional arg MODE is line-only', then highlight only the line. If optional arg MODE is col-only', then highlight only the column.
Interactively:
A non-negative prefix argument uses MODE line-only'. A negative prefix argument uses MODE col-only'.
Optional arg NOMSG non-nil means show no message.
If the current buffer is not the same as the value of orig-buff', then indicate the buffer, as well as the position. Variable orig-buff' is not bound here; if you want to take advantage of this
feature in your code, then bind it.
Return current position as a marker." (interactive (list (and current-prefix-arg (if (wholenump (prefix-numeric-value current-prefix-arg)) 'line-only 'col-only)))) (when crosshairs-mode (crosshairs-mode -1)) (prog1 (point-marker) (unless (eq mode 'line-only) (require 'col-highlight nil t)) (unless (eq mode 'col-only) (require 'hl-line nil t)) (setq mark-active nil) (crosshairs-unhighlight 'even-if-frame-switch) (when (and (boundp 'global-hl-line-overlay) (not (eq mode 'col-only))) (unless global-hl-line-overlay (setq global-hl-line-overlay (make-overlay 1 1)) ; to be moved (overlay-put global-hl-line-overlay 'face hl-line-face)) (when (and (boundp 'global-hl-line-overlays) (not (member global-hl-line-overlay global-hl-line-overlays))) (push global-hl-line-overlay global-hl-line-overlays)) (overlay-put global-hl-line-overlay 'window (selected-window)) (hl-line-move global-hl-line-overlay)) (when (and (fboundp 'col-highlight-highlight) (not (eq mode 'line-only))) (redisplay t) ; Force a redisplay, or else it doesn't always show up. (col-highlight-highlight)) (when (or (boundp 'global-hl-line-overlay) (fboundp 'col-highlight-highlight)) (add-hook 'pre-command-hook 'crosshairs-unhighlight)) (unless nomsg (if (and (boundp 'orig-buff) (eq (current-buffer) orig-buff)) (message "Point: %d" (point)) (message "Buffer: `%s', Point: %d" (current-buffer) (point))))))
;;;###autoload (defun crosshairs-unhighlight (&optional arg) "Turn off crosshairs highlighting of current position. Optional arg nil means do nothing if this event is a frame switch." (interactive) (when (or arg (not (and (consp last-input-event) (eq (car last-input-event) 'switch-frame)))) (when (fboundp 'col-highlight-unhighlight) (col-highlight-unhighlight t)) (when (and (boundp 'global-hl-line-overlay) global-hl-line-overlay) ;; (when crosshairs-overlay-priority ;; (overlay-put global-hl-line-overlay 'priority nil)) (delete-overlay global-hl-line-overlay)) (when (fboundp 'global-hl-line-unhighlight-all) ; Emacs 24.4+ (global-hl-line-unhighlight-all)) (remove-hook 'pre-command-hook 'crosshairs-unhighlight)))
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
(provide 'crosshairs)
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;;; crosshairs.el ends here