1;;; gs.el --- interface to Ghostscript 2 3;; Copyright (C) 1998, 2001, 2002, 2003, 2004, 4;; 2005, 2006, 2007 Free Software Foundation, Inc. 5 6;; Maintainer: FSF 7;; Keywords: internal 8 9;; This file is part of GNU Emacs. 10 11;; GNU Emacs is free software; you can redistribute it and/or modify 12;; it under the terms of the GNU General Public License as published by 13;; the Free Software Foundation; either version 2, or (at your option) 14;; any later version. 15 16;; GNU Emacs is distributed in the hope that it will be useful, 17;; but WITHOUT ANY WARRANTY; without even the implied warranty of 18;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19;; GNU General Public License for more details. 20 21;; You should have received a copy of the GNU General Public License 22;; along with GNU Emacs; see the file COPYING. If not, write to the 23;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 24;; Boston, MA 02110-1301, USA. 25 26;;; Commentary: 27 28;; This code is experimental. Don't use it. 29 30;;; Code: 31 32(defvar gs-program "gs" 33 "The name of the Ghostscript interpreter.") 34 35 36(defvar gs-device "x11" 37 "The Ghostscript device to use to produce images.") 38 39 40(defvar gs-options 41 '("-q" 42 ;"-dNOPAUSE" 43 "-dSAFER" 44 "-dBATCH" 45 "-sDEVICE=<device>" 46 "<file>") 47 "List of command line arguments to pass to Ghostscript. 48Arguments may contain place-holders `<file>' for the name of the 49input file, and `<device>' for the device to use.") 50(put 'gs-options 'risky-local-variable t) 51 52(defun gs-options (device file) 53 "Return a list of command line options with place-holders replaced. 54DEVICE is the value to substitute for the place-holder `<device>', 55FILE is the value to substitute for the place-holder `<file>'." 56 (mapcar #'(lambda (option) 57 (setq option (replace-regexp-in-string "<device>" device option) 58 option (replace-regexp-in-string "<file>" file option))) 59 gs-options)) 60 61;; The GHOSTVIEW property (taken from gv 3.5.8). 62;; 63;; Type: 64;; 65;; STRING 66;; 67;; Parameters: 68;; 69;; BPIXMAP ORIENT LLX LLY URX URY XDPI YDPI [LEFT BOTTOM TOP RIGHT] 70;; 71;; Scanf format: "%d %d %d %d %d %d %f %f %d %d %d %d" 72;; 73;; Explanation of parameters: 74;; 75;; BPIXMAP: pixmap id of the backing pixmap for the window. If no 76;; pixmap is to be used, this parameter should be zero. This 77;; parameter must be zero when drawing on a pixmap. 78;; 79;; ORIENT: orientation of the page. The number represents clockwise 80;; rotation of the paper in degrees. Permitted values are 0, 90, 180, 81;; 270. 82;; 83;; LLX, LLY, URX, URY: Bounding box of the drawable. The bounding box 84;; is specified in PostScript points in default user coordinates. 85;; 86;; XDPI, YDPI: Resolution of window. (This can be derived from the 87;; other parameters, but not without roundoff error. These values are 88;; included to avoid this error.) 89;; 90;; LEFT, BOTTOM, TOP, RIGHT: (optional) Margins around the window. 91;; The margins extend the imageable area beyond the boundaries of the 92;; window. This is primarily used for popup zoom windows. I have 93;; encountered several instances of PostScript programs that position 94;; themselves with respect to the imageable area. The margins are 95;; specified in PostScript points. If omitted, the margins are 96;; assumed to be 0. 97 98(defun gs-width-in-pt (frame pixel-width) 99 "Return, on FRAME, pixel width PIXEL-WIDTH tranlated to pt." 100 (let ((mm (* (float pixel-width) 101 (/ (float (x-display-mm-width frame)) 102 (float (x-display-pixel-width frame)))))) 103 (/ (* 25.4 mm) 72.0))) 104 105 106(defun gs-height-in-pt (frame pixel-height) 107 "Return, on FRAME, pixel height PIXEL-HEIGHT tranlated to pt." 108 (let ((mm (* (float pixel-height) 109 (/ (float (x-display-mm-height frame)) 110 (float (x-display-pixel-height frame)))))) 111 (/ (* 25.4 mm) 72.0))) 112 113 114(defun gs-set-ghostview-window-prop (frame spec img-width img-height) 115 "Set the `GHOSTVIEW' window property of FRAME. 116SPEC is a GS image specification. IMG-WIDTH is the width of the 117requested image, and IMG-HEIGHT is the height of the requested 118image in pixels." 119 (let* ((box (plist-get (cdr spec) :bounding-box)) 120 (llx (elt box 0)) 121 (lly (elt box 1)) 122 (urx (elt box 2)) 123 (ury (elt box 3)) 124 (rotation (or (plist-get (cdr spec) :rotate) 0)) 125 ;; The pixel width IMG-WIDTH of the pixmap gives the 126 ;; dots, URX - LLX give the inch. 127 (in-width (/ (- urx llx) 72.0)) 128 (in-height (/ (- ury lly) 72.0)) 129 (xdpi (/ img-width in-width)) 130 (ydpi (/ img-height in-height))) 131 (x-change-window-property "GHOSTVIEW" 132 (format "0 %d %d %d %d %d %g %g" 133 rotation llx lly urx ury xdpi ydpi) 134 frame))) 135 136 137(defun gs-set-ghostview-colors-window-prop (frame pixel-colors) 138 "Set the `GHOSTVIEW_COLORS' environment variable depending on FRAME." 139 (let ((mode (cond ((x-display-color-p frame) "Color") 140 ((x-display-grayscale-p frame) "Grayscale") 141 (t "Monochrome")))) 142 (x-change-window-property "GHOSTVIEW_COLORS" 143 (format "%s %s" mode pixel-colors) 144 frame))) 145 146 147; 148;;;###autoload 149(defun gs-load-image (frame spec img-width img-height window-and-pixmap-id 150 pixel-colors) 151 "Load a PS image for display on FRAME. 152SPEC is an image specification, IMG-HEIGHT and IMG-WIDTH are width 153and height of the image in pixels. WINDOW-AND-PIXMAP-ID is a string of 154the form \"WINDOW-ID PIXMAP-ID\". Value is non-nil if successful." 155 (unwind-protect 156 (let ((file (plist-get (cdr spec) :file)) 157 gs 158 (timeout 40)) 159 ;; Wait while property gets freed from a previous ghostscript process 160 ;; sit-for returns nil as soon as input starts being 161 ;; available, so if we want to give GhostScript a reasonable 162 ;; chance of starting up, we better use sleep-for. We let 163 ;; sleep-for wait only half the time because if input is 164 ;; available, it is more likely that we don't care that much 165 ;; about garbled redisplay and are in a hurry. 166 (while (and 167 ;; Wait while the property is not yet available 168 (not (zerop (length (x-window-property "GHOSTVIEW" 169 frame)))) 170 ;; The following was an alternative condition: wait 171 ;; while there is still a process running. The idea 172 ;; was to avoid contention between processes. Turned 173 ;; out even more sluggish. 174 ;; (get-buffer-process "*GS*") 175 (not (zerop timeout))) 176 (unless (sit-for 0 100 t) 177 (sleep-for 0 50)) 178 (setq timeout (1- timeout))) 179 180 ;; No use waiting longer. We might want to try killing off 181 ;; stuck processes, but there is no point in doing so: either 182 ;; they are stuck for good, in which case the user would 183 ;; probably be responsible for that, and killing them off will 184 ;; make debugging harder, or they are not. In that case, they 185 ;; will cause incomplete displays. But the same will happen 186 ;; if they are killed, anyway. The whole is rather 187 ;; disconcerting, and fast scrolling through a dozen images 188 ;; will make Emacs freeze for a while. The alternatives are a) 189 ;; proper implementation not waiting at all but creating 190 ;; appropriate queues, or b) permanently bad display due to 191 ;; bad cached images. So remember that this 192 ;; is just a hack and if people don't like the behaviour, they 193 ;; will most likely like the easy alternatives even less. 194 ;; And at least the image cache will make the delay apparent 195 ;; just once. 196 (gs-set-ghostview-window-prop frame spec img-width img-height) 197 (gs-set-ghostview-colors-window-prop frame pixel-colors) 198 (setenv "GHOSTVIEW" window-and-pixmap-id) 199 (setq gs (apply 'start-process "gs" "*GS*" gs-program 200 (gs-options gs-device file))) 201 (set-process-query-on-exit-flag gs nil) 202 gs) 203 nil)) 204 205 206;(defun gs-put-tiger () 207; (let* ((ps-file "/usr/local/share/ghostscript/5.10/examples/tiger.ps") 208; (spec `(image :type postscript 209; :pt-width 200 :pt-height 200 210; :bounding-box (22 171 567 738) 211; :file ,ps-file))) 212; (put-text-property 1 2 'display spec))) 213; 214 215(provide 'gs) 216 217;;; arch-tag: 06ab51b8-4932-4cfe-9f60-b924a8edb3f0 218;;; gs.el ends here 219