;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2016, 2017, 2018 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2015 Andy Wingo <wingo@igalia.com>
;;;
;;; This file is part of GNU Guix.
;;;
;;; GNU Guix 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 Guix 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 Guix.  If not, see <http://www.gnu.org/licenses/>.

(define-module (gnu build svg)
  #:use-module (rsvg)
  #:use-module (cairo)
  #:use-module (srfi srfi-11)
  #:export (svg->png))

(define* (downscaled-surface surface
                             #:key
                             source-width source-height
                             width height)
  "Return a new rendering context where SURFACE is scaled to WIDTH x HEIGHT."
  (let ((cr (cairo-create (cairo-image-surface-create 'argb32
                                                      width height))))
    (cairo-scale cr (/ width source-width) (/ height source-height))
    (cairo-set-source-surface cr surface 0 0)
    (cairo-pattern-set-filter (cairo-get-source cr) 'best)
    (cairo-rectangle cr 0 0 source-width source-height)
    (cairo-fill cr)
    cr))

(define* (svg->png in-svg out-png
                   #:key width height)
  "Render the file at IN-SVG as a PNG file in OUT-PNG.  When WIDTH and HEIGHT
are provided, use them as the dimensions of OUT-PNG; otherwise preserve the
dimensions of IN-SVG."
  (define svg
    (rsvg-handle-new-from-file in-svg))

  (let-values (((origin-width origin-height em ex)
                (rsvg-handle-get-dimensions svg)))
    (let* ((surf (cairo-image-surface-create 'argb32
                                             origin-width origin-height))
           (cr   (cairo-create surf)))
      (rsvg-handle-render-cairo svg cr)
      (cairo-surface-flush surf)
      (let ((cr (if (and width height
                         (not (= width origin-width))
                         (not (= height origin-height)))
                    (downscaled-surface surf
                                        #:source-width origin-width
                                        #:source-height origin-height
                                        #:width width
                                        #:height height)
                    cr)))
        (cairo-surface-write-to-png (cairo-get-target cr) out-png)))))

;;; svg.scm ends here
sg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-06-27 23:33:48 +0200'>2019-06-27</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=5cc1075a76392666d3d733837f5c6252b1e48002'>Merge branch 'master' into core-updates</a></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-06-27 11:14:42 +0200'>2019-06-27</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=c30d117822a8ca26cd8c06c0a3974955bef68eac'>tests: Avoid TCP port collision between lint.scm and guix-daemon.sh.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-06-14 21:57:39 +0200'>2019-06-14</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=1ba0b1e6ec41afd94a3c5f907b1122204dcb5d9d'>packages: Remove 'search-bootstrap-binary'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-02-04 00:03:30 +0100'>2019-02-04</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=a87d66f371da2a84d7bba1cae58b71c9c9af73aa'>daemon: Rename 'NIX_STATE_DIR' and 'NIX_DB_DIR' environment variables.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2019-01-21 23:09:55 +0100'>2019-01-21</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=f9e8a12379c6fefc9e5c3c7fc3926599bbefc013'>store: Rename '&amp;nix-error' to '&amp;store-error'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2018-04-19 19:06:26 +0200'>2018-04-19</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=5cefb13ddd4d51a63a387e74c138035b7b8b8537'>guix-daemon: Disable garbage collection for remote connections.</a><span class='msg-avail'>...</span></td><td>Roel Janssen</td></tr>
<tr><td><span title='2018-01-07 23:47:22 +0100'>2018-01-07</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=29a686688674dc875775305312513405fa396a06'>daemon: Add gzip log compression.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-06-22 10:59:07 +0200'>2017-06-22</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=1071f781d97509347144754b3248581cf7c6c1d5'>daemon: '--listen' can be passed several times, can specify TCP endpoints.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-06-04 00:35:55 +0200'>2017-06-04</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=2ca9f51ec8125c0124362300853365a1a6c76ee5'>daemon: Add '--timeout' and '--max-silent-time'.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2017-01-15 15:43:22 +0100'>2017-01-15</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=deac976d3d26c7b85b9c90efb424b0aa94f1027c'>daemon: Client settings no longer override daemon settings.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2016-03-02 14:47:07 +0100'>2016-03-02</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=442a6ff5eae094f1fd4e09241a2f35c33ab908da'>tests: Disable grafts by default.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2015-09-28 22:54:04 +0200'>2015-09-28</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=16748d80158875ae4cd54270be683fcf9c5d5169'>store: Add 'query-failed-paths' and 'clear-failed-paths' RPCs.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2015-07-13 18:29:01 +0200'>2015-07-13</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=24f5aaaf24e009de7f7402f2d311a26cafbf4f4a'>substitute: Honor "substitute-urls" option passed by "untrusted" clients.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2015-03-26 23:54:59 +0100'>2015-03-26</span></td><td><a href='/guix/commit/tests/guix-daemon.sh?id=122c87ead0452a3042f1d42db9986a41218732cf'>Fix remaining references to "substitute-binary".</a><span class='msg-avail'>...</span></td><td>Taylan Ulrich Bayırlı/Kammer</td></tr>