img: Add back support for SVG images, bypassing ImageMagick and simply passing the SVG through to the browser

SVG scaling by img directives has subtly changed; where before size=wxh
would preserve aspect ratio, this cannot be done when passing them through
and so specifying both a width and height can change the SVG's aspect
ratio.

(This patch looks significantly more complex than it was, because a large
block of code had to be indented.)

[smcv: drop trailing whitespace, fix some spelling]

1 files changed, 7 insertions, 5 deletions

diff --git a/doc/ikiwiki/directive/img.mdwn b/doc/ikiwiki/directive/img.mdwn
index 08d158987..fa3b40f50 100644
--- a/doc/ikiwiki/directive/img.mdwn
+++ b/doc/ikiwiki/directive/img.mdwn
@@ -12,11 +12,13 @@ providing a link to a full-size version.
 The image file will be searched for using the same rules as used to find
 the file pointed to by a [[ikiwiki/WikiLink]].
 
-The `size` parameter is optional, defaulting to full size. Note that the
-original image's aspect ratio is always preserved, even if this means
-making the image smaller than the specified size. You can also specify only
-the width or the height, and the other value will be calculated based on
-it: "200x", "x200"
+The `size` parameter is optional, defaulting to full size.
+You can specify only the width or the height, and the other value will
+be calculated based on it: "200x", "x200".
+
+If you specify both the width and height, the original image's aspect
+ratio will be preserved, even if this means making the image smaller
+than the specified size. (However, this is not done for svg images.)
 
 You can also pass `alt`, `title`, `class`, `align`, `id`, `hspace`, and
 `vspace` parameters.