;;; 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
alue='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Pierre Neidhardt &lt;mail@ambrevar.xyz&gt;</td><td class='right'>2019-11-04 12:34:16 +0100</td></tr>
<tr><th>committer</th><td>Pierre Neidhardt &lt;mail@ambrevar.xyz&gt;</td><td class='right'>2019-11-04 12:34:16 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/guix/commit/gnu/services/vpn.scm?id=ef189ab3b82a29991d9952b6c98b2f8c7acc7c88'>ef189ab3b82a29991d9952b6c98b2f8c7acc7c88</a> (<a href='/guix/patch/gnu/services/vpn.scm?id=ef189ab3b82a29991d9952b6c98b2f8c7acc7c88'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/guix/tree/?id=ef189ab3b82a29991d9952b6c98b2f8c7acc7c88'>644da991180bdd8ebdb6afea2f95968220003b94</a> /<a href='/guix/tree/gnu/services/vpn.scm?id=ef189ab3b82a29991d9952b6c98b2f8c7acc7c88'>gnu/services/vpn.scm</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/guix/commit/gnu/services/vpn.scm?id=d258d9c7d222e6b64531c14293f41bd8d62ea4f7'>d258d9c7d222e6b64531c14293f41bd8d62ea4f7</a> (<a href='/guix/diff/gnu/services/vpn.scm?id=ef189ab3b82a29991d9952b6c98b2f8c7acc7c88&amp;id2=d258d9c7d222e6b64531c14293f41bd8d62ea4f7'>diff</a>)</td></tr><tr><th>download</th><td colspan='2' class='oid'><a href='/guix/snapshot/guix-ef189ab3b82a29991d9952b6c98b2f8c7acc7c88.tar.gz'>guix-ef189ab3b82a29991d9952b6c98b2f8c7acc7c88.tar.gz</a><br/><a href='/guix/snapshot/guix-ef189ab3b82a29991d9952b6c98b2f8c7acc7c88.zip'>guix-ef189ab3b82a29991d9952b6c98b2f8c7acc7c88.zip</a><br/></td></tr></table>
<div class='commit-subject'>gnu: emacs-unfill: Use `version' instead of hard-coding git-reference.</div><div class='commit-msg'>* gnu/packages/emacs-xyz.scm (emacs-unfill)[source]: Use `version' in `commit'
  field.
</div><div class='diffstat-header'><a href='/guix/diff/?id=ef189ab3b82a29991d9952b6c98b2f8c7acc7c88'>Diffstat</a> (limited to 'gnu/services/vpn.scm')</div><table summary='diffstat' class='diffstat'></table><div class='diffstat-summary'>0 files changed, 0 insertions, 0 deletions</div><table summary='diff' class='diff'><tr><td></td></tr></table></div> <!-- class=content -->
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