Commit | Line | Data |
---|---|---|
6bf7aab6 | 1 | @c This is part of the Emacs manual. |
b65d8176 TTN |
2 | @c Copyright (C) 1985, 1986, 1987, 1993, 1994, 1995, 1997, 2002, 2003, |
3 | @c 2004, 2005 Free Software Foundation, Inc. | |
6bf7aab6 DL |
4 | @c See file emacs.texi for copying conditions. |
5 | @node Picture, Sending Mail, Abbrevs, Top | |
6 | @chapter Editing Pictures | |
7 | @cindex pictures | |
8 | @cindex making pictures out of text characters | |
9 | @findex edit-picture | |
10 | ||
11 | To edit a picture made out of text characters (for example, a picture | |
12 | of the division of a register into fields, as a comment in a program), | |
13 | use the command @kbd{M-x edit-picture} to enter Picture mode. | |
14 | ||
15 | In Picture mode, editing is based on the @dfn{quarter-plane} model of | |
16 | text, according to which the text characters lie studded on an area that | |
17 | stretches infinitely far to the right and downward. The concept of the end | |
18 | of a line does not exist in this model; the most you can say is where the | |
19 | last nonblank character on the line is found. | |
20 | ||
21 | Of course, Emacs really always considers text as a sequence of | |
22 | characters, and lines really do have ends. But Picture mode replaces | |
23 | the most frequently-used commands with variants that simulate the | |
24 | quarter-plane model of text. They do this by inserting spaces or by | |
25 | converting tabs to spaces. | |
26 | ||
27 | Most of the basic editing commands of Emacs are redefined by Picture mode | |
28 | to do essentially the same thing but in a quarter-plane way. In addition, | |
29 | Picture mode defines various keys starting with the @kbd{C-c} prefix to | |
30 | run special picture editing commands. | |
31 | ||
32 | One of these keys, @kbd{C-c C-c}, is pretty important. Often a | |
33 | picture is part of a larger file that is usually edited in some other | |
34 | major mode. @kbd{M-x edit-picture} records the name of the previous | |
35 | major mode so you can use the @kbd{C-c C-c} command | |
36 | (@code{picture-mode-exit}) later to go back to that mode. @kbd{C-c C-c} | |
37 | also deletes spaces from the ends of lines, unless given a numeric | |
38 | argument. | |
39 | ||
40 | The special commands of Picture mode all work in other modes (provided | |
41 | the @file{picture} library is loaded), but are not bound to keys except | |
42 | in Picture mode. The descriptions below talk of moving ``one column'' | |
43 | and so on, but all the picture mode commands handle numeric arguments as | |
44 | their normal equivalents do. | |
45 | ||
46 | @vindex picture-mode-hook | |
47 | Turning on Picture mode runs the hook @code{picture-mode-hook} | |
1eeda449 RS |
48 | (@pxref{Hooks}). Additional extensions to Picture mode can be found |
49 | in @file{artist.el}. | |
6bf7aab6 DL |
50 | |
51 | @menu | |
52 | * Basic Picture:: Basic concepts and simple commands of Picture Mode. | |
53 | * Insert in Picture:: Controlling direction of cursor motion | |
54 | after "self-inserting" characters. | |
55 | * Tabs in Picture:: Various features for tab stops and indentation. | |
56 | * Rectangles in Picture:: Clearing and superimposing rectangles. | |
57 | @end menu | |
58 | ||
59 | @node Basic Picture, Insert in Picture, Picture, Picture | |
60 | @section Basic Editing in Picture Mode | |
61 | ||
62 | @findex picture-forward-column | |
63 | @findex picture-backward-column | |
64 | @findex picture-move-down | |
65 | @findex picture-move-up | |
66 | @cindex editing in Picture mode | |
67 | ||
68 | Most keys do the same thing in Picture mode that they usually do, but | |
69 | do it in a quarter-plane style. For example, @kbd{C-f} is rebound to | |
70 | run @code{picture-forward-column}, a command which moves point one | |
71 | column to the right, inserting a space if necessary so that the actual | |
72 | end of the line makes no difference. @kbd{C-b} is rebound to run | |
73 | @code{picture-backward-column}, which always moves point left one | |
74 | column, converting a tab to multiple spaces if necessary. @kbd{C-n} and | |
75 | @kbd{C-p} are rebound to run @code{picture-move-down} and | |
76 | @code{picture-move-up}, which can either insert spaces or convert tabs | |
77 | as necessary to make sure that point stays in exactly the same column. | |
78 | @kbd{C-e} runs @code{picture-end-of-line}, which moves to after the last | |
79 | nonblank character on the line. There is no need to change @kbd{C-a}, | |
80 | as the choice of screen model does not affect beginnings of | |
81 | lines. | |
82 | ||
83 | @findex picture-newline | |
84 | Insertion of text is adapted to the quarter-plane screen model through | |
85 | the use of Overwrite mode (@pxref{Minor Modes}). Self-inserting characters | |
86 | replace existing text, column by column, rather than pushing existing text | |
87 | to the right. @key{RET} runs @code{picture-newline}, which just moves to | |
88 | the beginning of the following line so that new text will replace that | |
89 | line. | |
90 | ||
91 | @findex picture-backward-clear-column | |
92 | @findex picture-clear-column | |
93 | @findex picture-clear-line | |
61ff7bed RS |
94 | In Picture mode, the commands that normally delete or kill text, |
95 | instead erase text (replacing it with spaces). @key{DEL} | |
96 | (@code{picture-backward-clear-column}) replaces the preceding | |
97 | character with a space rather than removing it; this moves point | |
98 | backwards. @kbd{C-d} (@code{picture-clear-column}) replaces the next | |
99 | character or characters with spaces, but does not move point. (If you | |
100 | want to clear characters to spaces and move forward over them, use | |
6bf7aab6 | 101 | @key{SPC}.) @kbd{C-k} (@code{picture-clear-line}) really kills the |
61ff7bed | 102 | contents of lines, but does not delete the newlines from the buffer. |
6bf7aab6 DL |
103 | |
104 | @findex picture-open-line | |
105 | To do actual insertion, you must use special commands. @kbd{C-o} | |
61ff7bed RS |
106 | (@code{picture-open-line}) creates a blank line after the current |
107 | line; it never splits a line. @kbd{C-M-o} (@code{split-line}) makes | |
108 | sense in Picture mode, so it is not changed. @kbd{C-j} | |
109 | (@code{picture-duplicate-line}) inserts another line with the same | |
110 | contents below the current line. | |
6bf7aab6 DL |
111 | |
112 | @kindex C-c C-d @r{(Picture mode)} | |
113 | To do actual deletion in Picture mode, use @kbd{C-w}, @kbd{C-c C-d} | |
114 | (which is defined as @code{delete-char}, as @kbd{C-d} is in other | |
115 | modes), or one of the picture rectangle commands (@pxref{Rectangles in | |
116 | Picture}). | |
117 | ||
118 | @node Insert in Picture, Tabs in Picture, Basic Picture, Picture | |
119 | @section Controlling Motion after Insert | |
120 | ||
121 | @findex picture-movement-up | |
122 | @findex picture-movement-down | |
123 | @findex picture-movement-left | |
124 | @findex picture-movement-right | |
125 | @findex picture-movement-nw | |
126 | @findex picture-movement-ne | |
127 | @findex picture-movement-sw | |
128 | @findex picture-movement-se | |
129 | @kindex C-c < @r{(Picture mode)} | |
130 | @kindex C-c > @r{(Picture mode)} | |
131 | @kindex C-c ^ @r{(Picture mode)} | |
132 | @kindex C-c . @r{(Picture mode)} | |
133 | @kindex C-c ` @r{(Picture mode)} | |
134 | @kindex C-c ' @r{(Picture mode)} | |
135 | @kindex C-c / @r{(Picture mode)} | |
136 | @kindex C-c \ @r{(Picture mode)} | |
137 | Since ``self-inserting'' characters in Picture mode overwrite and move | |
138 | point, there is no essential restriction on how point should be moved. | |
139 | Normally point moves right, but you can specify any of the eight | |
140 | orthogonal or diagonal directions for motion after a ``self-inserting'' | |
141 | character. This is useful for drawing lines in the buffer. | |
142 | ||
143 | @table @kbd | |
144 | @item C-c < | |
61ff7bed | 145 | @itemx C-c @key{LEFT} |
6bf7aab6 DL |
146 | Move left after insertion (@code{picture-movement-left}). |
147 | @item C-c > | |
61ff7bed | 148 | @itemx C-c @key{RIGHT} |
6bf7aab6 DL |
149 | Move right after insertion (@code{picture-movement-right}). |
150 | @item C-c ^ | |
61ff7bed | 151 | @itemx C-c @key{UP} |
6bf7aab6 DL |
152 | Move up after insertion (@code{picture-movement-up}). |
153 | @item C-c . | |
61ff7bed | 154 | @itemx C-c @key{DOWN} |
6bf7aab6 DL |
155 | Move down after insertion (@code{picture-movement-down}). |
156 | @item C-c ` | |
61ff7bed | 157 | @itemx C-c @key{HOME} |
6bf7aab6 DL |
158 | Move up and left (``northwest'') after insertion (@code{picture-movement-nw}). |
159 | @item C-c ' | |
61ff7bed | 160 | @itemx C-c @key{PAGEUP} |
6bf7aab6 DL |
161 | Move up and right (``northeast'') after insertion |
162 | (@code{picture-movement-ne}). | |
163 | @item C-c / | |
61ff7bed | 164 | @itemx C-c @key{END} |
6bf7aab6 DL |
165 | Move down and left (``southwest'') after insertion |
166 | @*(@code{picture-movement-sw}). | |
167 | @item C-c \ | |
61ff7bed | 168 | @itemx C-c @key{PAGEDOWN} |
6bf7aab6 DL |
169 | Move down and right (``southeast'') after insertion |
170 | @*(@code{picture-movement-se}). | |
171 | @end table | |
172 | ||
173 | @kindex C-c C-f @r{(Picture mode)} | |
174 | @kindex C-c C-b @r{(Picture mode)} | |
175 | @findex picture-motion | |
176 | @findex picture-motion-reverse | |
177 | Two motion commands move based on the current Picture insertion | |
178 | direction. The command @kbd{C-c C-f} (@code{picture-motion}) moves in the | |
179 | same direction as motion after ``insertion'' currently does, while @kbd{C-c | |
180 | C-b} (@code{picture-motion-reverse}) moves in the opposite direction. | |
181 | ||
182 | @node Tabs in Picture, Rectangles in Picture, Insert in Picture, Picture | |
183 | @section Picture Mode Tabs | |
184 | ||
185 | @kindex M-TAB @r{(Picture mode)} | |
186 | @findex picture-tab-search | |
187 | @vindex picture-tab-chars | |
188 | Two kinds of tab-like action are provided in Picture mode. Use | |
189 | @kbd{M-@key{TAB}} (@code{picture-tab-search}) for context-based tabbing. | |
190 | With no argument, it moves to a point underneath the next | |
191 | ``interesting'' character that follows whitespace in the previous | |
192 | nonblank line. ``Next'' here means ``appearing at a horizontal position | |
193 | greater than the one point starts out at.'' With an argument, as in | |
194 | @kbd{C-u M-@key{TAB}}, this command moves to the next such interesting | |
195 | character in the current line. @kbd{M-@key{TAB}} does not change the | |
196 | text; it only moves point. ``Interesting'' characters are defined by | |
197 | the variable @code{picture-tab-chars}, which should define a set of | |
198 | characters. The syntax for this variable is like the syntax used inside | |
199 | of @samp{[@dots{}]} in a regular expression---but without the @samp{[} | |
200 | and the @samp{]}. Its default value is @code{"!-~"}. | |
201 | ||
202 | @findex picture-tab | |
203 | @key{TAB} itself runs @code{picture-tab}, which operates based on the | |
204 | current tab stop settings; it is the Picture mode equivalent of | |
205 | @code{tab-to-tab-stop}. Normally it just moves point, but with a numeric | |
206 | argument it clears the text that it moves over. | |
207 | ||
208 | @kindex C-c TAB @r{(Picture mode)} | |
209 | @findex picture-set-tab-stops | |
210 | The context-based and tab-stop-based forms of tabbing are brought | |
211 | together by the command @kbd{C-c @key{TAB}} (@code{picture-set-tab-stops}). | |
212 | This command sets the tab stops to the positions which @kbd{M-@key{TAB}} | |
213 | would consider significant in the current line. The use of this command, | |
214 | together with @key{TAB}, can get the effect of context-based tabbing. But | |
215 | @kbd{M-@key{TAB}} is more convenient in the cases where it is sufficient. | |
216 | ||
217 | It may be convenient to prevent use of actual tab characters in | |
218 | pictures. For example, this prevents @kbd{C-x @key{TAB}} from messing | |
219 | up the picture. You can do this by setting the variable | |
220 | @code{indent-tabs-mode} to @code{nil}. @xref{Just Spaces}. | |
221 | ||
222 | @node Rectangles in Picture,, Tabs in Picture, Picture | |
223 | @section Picture Mode Rectangle Commands | |
224 | @cindex rectangles and Picture mode | |
225 | @cindex Picture mode and rectangles | |
226 | ||
227 | Picture mode defines commands for working on rectangular pieces of the | |
228 | text in ways that fit with the quarter-plane model. The standard rectangle | |
229 | commands may also be useful (@pxref{Rectangles}). | |
230 | ||
231 | @table @kbd | |
232 | @item C-c C-k | |
233 | Clear out the region-rectangle with spaces | |
234 | (@code{picture-clear-rectangle}). With argument, delete the text. | |
235 | @item C-c C-w @var{r} | |
58fa012d | 236 | Similar, but save rectangle contents in register @var{r} first |
6bf7aab6 DL |
237 | (@code{picture-clear-rectangle-to-register}). |
238 | @item C-c C-y | |
239 | Copy last killed rectangle into the buffer by overwriting, with upper | |
240 | left corner at point (@code{picture-yank-rectangle}). With argument, | |
241 | insert instead. | |
242 | @item C-c C-x @var{r} | |
243 | Similar, but use the rectangle in register @var{r} | |
244 | (@code{picture-yank-rectangle-from-register}). | |
245 | @end table | |
246 | ||
247 | @kindex C-c C-k @r{(Picture mode)} | |
248 | @kindex C-c C-w @r{(Picture mode)} | |
249 | @findex picture-clear-rectangle | |
250 | @findex picture-clear-rectangle-to-register | |
251 | The picture rectangle commands @kbd{C-c C-k} | |
252 | (@code{picture-clear-rectangle}) and @kbd{C-c C-w} | |
253 | (@code{picture-clear-rectangle-to-register}) differ from the standard | |
254 | rectangle commands in that they normally clear the rectangle instead of | |
255 | deleting it; this is analogous with the way @kbd{C-d} is changed in Picture | |
256 | mode. | |
257 | ||
258 | However, deletion of rectangles can be useful in Picture mode, so | |
259 | these commands delete the rectangle if given a numeric argument. | |
260 | @kbd{C-c C-k} either with or without a numeric argument saves the | |
261 | rectangle for @kbd{C-c C-y}. | |
262 | ||
263 | @kindex C-c C-y @r{(Picture mode)} | |
264 | @kindex C-c C-x @r{(Picture mode)} | |
265 | @findex picture-yank-rectangle | |
266 | @findex picture-yank-rectangle-from-register | |
267 | The Picture mode commands for yanking rectangles differ from the | |
58fa012d EZ |
268 | standard ones in that they overwrite instead of inserting. This is |
269 | the same way that Picture mode insertion of other text differs from | |
270 | other modes. @kbd{C-c C-y} (@code{picture-yank-rectangle}) inserts | |
271 | (by overwriting) the rectangle that was most recently killed, while | |
272 | @kbd{C-c C-x} (@code{picture-yank-rectangle-from-register}) does | |
273 | likewise for the rectangle found in a specified register. | |
ab5796a9 MB |
274 | |
275 | @ignore | |
276 | arch-tag: b7589747-683c-4f40-aed8-1b10403cb666 | |
277 | @end ignore |