SVG support on windows (or lack thereof)

[Antoine Martin]

Some apps only supply an SVG icon (ie: wine notepad).
Either we convert those on the fly to another format (how?) and cache this on disk.
Or we get Windows/gtk to play nice and load the svg pixbuf loader...

[Antoine Martin]

Tried newer gtk and got this:

Unable to load image-loading module: c:/devel/target/24657c578dad0b54d4855b1780ade31a/lib/gtk-2.0/2.10.0/loaders/libpixbufloader-png.dll: The specified module could not be found.

Doesn't look like something we should try to fix here, the problem is upstream.

[Antoine Martin]

With the current version of gtk we ship, this is what happens when we try to load an SVG on MS Windows:

GError: Unable to load image-loading module: D:\Windows-Shifter/lib/gtk-2.0/2.10.0/loaders/svg_loader.dll: The specified module could not be found.

There is some sample code for rendering SVGs on win32 using ctypes:
​http://www.cairographics.org/cookbook/librsvgpython/

Problem is that we get into DLL-hell: we need to bring an unknown amount of dependencies with it, see:
​http://www.nabble.com/wxSVG---an-SVG-solution--td19097413.html
,
​http://www.mail-archive.com/[email protected]/msg11736.html
and
​http://www.nabble.com/Nmap-4.85b1->>-zenmap.exe-:-librsvg-2-2.dll-not-found!-td21691797.html

[Antoine Martin]

In the meantime, we could just send the SVG icons to the clients that support it. Not hard, but tedious as we would need to carry a flag with the icon data to avoid sending it to the win32 clients.

[Antoine Martin]

more info about svg for win32: ​http://www.cairographics.org/cairo_rsvg_and_python_in_windows/

[Antoine Martin]

Warning dialog fixed by upgrading the build environment to the latest GTK release.

See r1505 and r1506

Still need to check that the rsvg dll does its job, but at least it stopped moaning!

[Antoine Martin]

SVG loader added to gdk-pixbuf.loaders

using instructions found ​here

Why is it so bloody hard???

Used relative path (by hand) after generating the file, as it will be loaded from the py2exe created dir.
Removed DLLs from svn: r1529

[Antoine Martin]

Tested on brand new install of XP (with MSVCR90.DLL but that's another matter... see #68)

[Antoine Martin]

For reference, here is the list of DLLs used:

freetype6.dll
intl.dll
libatk-1.0-0.dll
libcairo-2.dll
libcroco-0.6-3.dll
libexpat-1.dll
libfontconfig-1.dll
libgailutil-18.dll
libgdk-win32-2.0-0.dll
libgdk_pixbuf-2.0-0.dll
libgio-2.0-0.dll
libglib-2.0-0.dll
libgmodule-2.0-0.dll
libgobject-2.0-0.dll
libgsf-1-114.dll
libgsf-gnome-1-114.dll
libgsf-win32-1-114.dll
libgthread-2.0-0.dll
libgtk-win32-2.0-0.dll
libjpeg-7.dll
libjpeg-7_1.dll
libpango-1.0-0.dll
libpangocairo-1.0-0.dll
libpangoft2-1.0-0.dll
libpangowin32-1.0-0.dll
libpng12-0.dll
librsvg-2-2.dll
libtiff-3.dll
libtiffxx-3.dll
libxml2-2.dll
zlib1.dll
libbz2.dll.a
zdll.exp
zdll.lib
libpixmap.dll
libsvg.dll
libwimp.dll
svg_loader.dll
libgail.dll

[Antoine Martin]

And here is the gdk-pixbuf.loaders that got generated (if you don't get SVG in there, it will not work...):

# GdkPixbuf Image Loader Modules file
# Automatically generated file, do not edit
# Created by gdk-pixbuf-query-loaders.exe from gtk+-2.18.5
#
# LoaderDir = lib/gtk-2.0/2.10.0/loaders
#
"./lib/gtk-2.0/2.10.0/loaders/svg_loader.dll"
"svg" 2 "gtk20" "Scalable Vector Graphics" "LGPL"
"image/svg+xml" "image/svg" "image/svg-xml" "image/vnd.adobe.svg+xml" "text/xml-svg" "image/svg+xml-compressed" ""
"svg" "svgz" "svg.gz" ""
" <svg" "*    " 100
" <!DOCTYPE svg" "*             " 100

[Antoine Martin]

Note: this no longer a problem with the latest PyGTK all-in-one installers which include svg support. see ​win32 dev for details.