1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
;;; gs.el --- interface to Ghostscript
;; Copyright (C) 1998, 2001-2011 Free Software Foundation, Inc.
;; Maintainer: FSF
;; Keywords: internal
;; This file is part of GNU Emacs.
;; GNU Emacs 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 of the License, or
;; (at your option) any later version.
;; GNU Emacs 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 GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;; This code is experimental. Don't use it.
;;; Code:
(defvar gs-program "gs"
"The name of the Ghostscript interpreter.")
(defvar gs-device "x11"
"The Ghostscript device to use to produce images.")
(defvar gs-options
'("-q"
;"-dNOPAUSE"
"-dSAFER"
"-dBATCH"
"-sDEVICE=<device>"
"<file>")
"List of command line arguments to pass to Ghostscript.
Arguments may contain place-holders `<file>' for the name of the
input file, and `<device>' for the device to use.")
(put 'gs-options 'risky-local-variable t)
(defun gs-options (device file)
"Return a list of command line options with place-holders replaced.
DEVICE is the value to substitute for the place-holder `<device>',
FILE is the value to substitute for the place-holder `<file>'."
(mapcar #'(lambda (option)
(setq option (replace-regexp-in-string "<device>" device option)
option (replace-regexp-in-string "<file>" file option)))
gs-options))
;; The GHOSTVIEW property (taken from gv 3.5.8).
;;
;; Type:
;;
;; STRING
;;
;; Parameters:
;;
;; BPIXMAP ORIENT LLX LLY URX URY XDPI YDPI [LEFT BOTTOM TOP RIGHT]
;;
;; Scanf format: "%d %d %d %d %d %d %f %f %d %d %d %d"
;;
;; Explanation of parameters:
;;
;; BPIXMAP: pixmap id of the backing pixmap for the window. If no
;; pixmap is to be used, this parameter should be zero. This
;; parameter must be zero when drawing on a pixmap.
;;
;; ORIENT: orientation of the page. The number represents clockwise
;; rotation of the paper in degrees. Permitted values are 0, 90, 180,
;; 270.
;;
;; LLX, LLY, URX, URY: Bounding box of the drawable. The bounding box
;; is specified in PostScript points in default user coordinates.
;;
;; XDPI, YDPI: Resolution of window. (This can be derived from the
;; other parameters, but not without roundoff error. These values are
;; included to avoid this error.)
;;
;; LEFT, BOTTOM, TOP, RIGHT: (optional) Margins around the window.
;; The margins extend the imageable area beyond the boundaries of the
;; window. This is primarily used for popup zoom windows. I have
;; encountered several instances of PostScript programs that position
;; themselves with respect to the imageable area. The margins are
;; specified in PostScript points. If omitted, the margins are
;; assumed to be 0.
(declare-function x-display-mm-width "xfns.c" (&optional terminal))
(declare-function x-display-pixel-width "xfns.c" (&optional terminal))
(defun gs-width-in-pt (frame pixel-width)
"Return, on FRAME, pixel width PIXEL-WIDTH translated to pt."
(let ((mm (* (float pixel-width)
(/ (float (x-display-mm-width frame))
(float (x-display-pixel-width frame))))))
(/ (* 25.4 mm) 72.0)))
(declare-function x-display-mm-height "xfns.c" (&optional terminal))
(declare-function x-display-pixel-height "xfns.c" (&optional terminal))
(defun gs-height-in-pt (frame pixel-height)
"Return, on FRAME, pixel height PIXEL-HEIGHT translated to pt."
(let ((mm (* (float pixel-height)
(/ (float (x-display-mm-height frame))
(float (x-display-pixel-height frame))))))
(/ (* 25.4 mm) 72.0)))
(declare-function x-change-window-property "xfns.c"
(prop value &optional frame type format outer-p))
(defun gs-set-ghostview-window-prop (frame spec img-width img-height)
"Set the `GHOSTVIEW' window property of FRAME.
SPEC is a GS image specification. IMG-WIDTH is the width of the
requested image, and IMG-HEIGHT is the height of the requested
image in pixels."
(let* ((box (plist-get (cdr spec) :bounding-box))
(llx (elt box 0))
(lly (elt box 1))
(urx (elt box 2))
(ury (elt box 3))
(rotation (or (plist-get (cdr spec) :rotate) 0))
;; The pixel width IMG-WIDTH of the pixmap gives the
;; dots, URX - LLX give the inch.
(in-width (/ (- urx llx) 72.0))
(in-height (/ (- ury lly) 72.0))
(xdpi (/ img-width in-width))
(ydpi (/ img-height in-height)))
(x-change-window-property "GHOSTVIEW"
(format "0 %d %d %d %d %d %g %g"
rotation llx lly urx ury xdpi ydpi)
frame)))
(declare-function x-display-grayscale-p "xfns.c" (&optional terminal))
(defun gs-set-ghostview-colors-window-prop (frame pixel-colors)
"Set the `GHOSTVIEW_COLORS' environment variable depending on FRAME."
(let ((mode (cond ((x-display-color-p frame) "Color")
((x-display-grayscale-p frame) "Grayscale")
(t "Monochrome"))))
(x-change-window-property "GHOSTVIEW_COLORS"
(format "%s %s" mode pixel-colors)
frame)))
(declare-function x-window-property "xfns.c"
(prop &optional frame type source delete-p vector-ret-p))
;;;###autoload
(defun gs-load-image (frame spec img-width img-height window-and-pixmap-id
pixel-colors)
"Load a PS image for display on FRAME.
SPEC is an image specification, IMG-HEIGHT and IMG-WIDTH are width
and height of the image in pixels. WINDOW-AND-PIXMAP-ID is a string of
the form \"WINDOW-ID PIXMAP-ID\". Value is non-nil if successful."
(unwind-protect
(let ((file (plist-get (cdr spec) :file))
gs
(timeout 40))
;; Wait while property gets freed from a previous ghostscript process
;; sit-for returns nil as soon as input starts being
;; available, so if we want to give GhostScript a reasonable
;; chance of starting up, we better use sleep-for. We let
;; sleep-for wait only half the time because if input is
;; available, it is more likely that we don't care that much
;; about garbled redisplay and are in a hurry.
(while (and
;; Wait while the property is not yet available
(not (zerop (length (x-window-property "GHOSTVIEW"
frame))))
;; The following was an alternative condition: wait
;; while there is still a process running. The idea
;; was to avoid contention between processes. Turned
;; out even more sluggish.
;; (get-buffer-process "*GS*")
(not (zerop timeout)))
(unless (sit-for 0.1 t)
(sleep-for 0.05))
(setq timeout (1- timeout)))
;; No use waiting longer. We might want to try killing off
;; stuck processes, but there is no point in doing so: either
;; they are stuck for good, in which case the user would
;; probably be responsible for that, and killing them off will
;; make debugging harder, or they are not. In that case, they
;; will cause incomplete displays. But the same will happen
;; if they are killed, anyway. The whole is rather
;; disconcerting, and fast scrolling through a dozen images
;; will make Emacs freeze for a while. The alternatives are a)
;; proper implementation not waiting at all but creating
;; appropriate queues, or b) permanently bad display due to
;; bad cached images. So remember that this
;; is just a hack and if people don't like the behavior, they
;; will most likely like the easy alternatives even less.
;; And at least the image cache will make the delay apparent
;; just once.
(gs-set-ghostview-window-prop frame spec img-width img-height)
(gs-set-ghostview-colors-window-prop frame pixel-colors)
(setenv "GHOSTVIEW" window-and-pixmap-id)
(setq gs (apply 'start-process "gs" "*GS*" gs-program
(gs-options gs-device file)))
(set-process-query-on-exit-flag gs nil)
gs)
nil))
;(defun gs-put-tiger ()
; (let* ((ps-file "/usr/local/share/ghostscript/5.10/examples/tiger.ps")
; (spec `(image :type postscript
; :pt-width 200 :pt-height 200
; :bounding-box (22 171 567 738)
; :file ,ps-file)))
; (put-text-property 1 2 'display spec)))
;
(provide 'gs)
;;; gs.el ends here
|
