525998 - Add support for SVG output format when printing to file for Gtk builds

Status: NEW

(Core :: Widget: Gtk, defect, P5)

Description

[Daniel Holbert [:dholbert]]

In Ubuntu Karmic, the Gnome "print" dialog's print-to-file mode includes an option for SVG output (along with PS and PDF).  However, if I select this mode in Firefox, the resulting ".svg" file *actually* contains postscript.

STEPS TO REPRODUCE:
 1. File | Print
 2. Select "Print To File" from the printer list
 3. Select "SVG" as the Output Format, and enter in a name for the file.
 4. Examine the resulting file

EXPECTED RESULTS: Outputted file should be an SVG (or, "SVG" output mode should not be available)
ACTUAL RESULTS: Examining the text of the outputted file shows that it's actually a postscript file.

VERSION INFO:
 * Ubuntu 9.10
 * Gnome 2.28.1
 * Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.3a1pre) Gecko/20091030 Minefield/3.7a1pre

Comment 1

[Daniel Holbert [:dholbert]]

I just tried printing "about:blank" once as Postscript and once as SVG, and the outputted files were identical. (aside from the "%%CreationDate:" header)

Comment 2

[Daniel Holbert [:dholbert]]

Attachment: screenshot: print dialog with SVG output option

Here's a screenshot of the print dialog that I get from Firefox, with "SVG" available as an output format.

Comment 3

[Michael Ventnor]

SVG is a new format in the print dialog we don't handle yet. I'm wondering if there's a way for us to tell GTK we don't support it.

Comment 4

[Robert O'Callahan (:roc) (email my personal email if necessary)]

We can support it. We just need to use the cairo SVG backend.

Comment 5

[Michael Ventnor]

Ah, of course.

Comment 6

[Michael Ventnor]

Attachment: Patch

This hould work in theory, but I can't get it to compile because it keeps giving this error during libxul linking:

In function `_cairo_svg_surface_emit_composite_pattern':
cairo-svg-surface.c:(.text+0x1cc0): undefined reference to `INT__moz_cairo_surface_write_to_png_stream'

I don't know how we build Cairo and I don't have the time right now to deal with it. Does anyone who understands this knows what's going on?

Comment 7

[Karl Tomlinson (:karlt)]

Looks like we are not compiling cairo-png.c

Comment 8

[Takeshi Kurosawa :takenspc]

Attachment: Updated patch

* Some libpng features which are disabled currently are enabled to compile cairo-png.c

* Use SVG 1.2 to adopt what gtk applications do.
Using SVG 1.1, cairo fallbacks almost contents and only renders last page.
Using SVG 1.2, cairo uses less fallback images and generates multi-page SVG using the SVG Print 1.2 elements.
# I wonder if there are any implementation of the SVG Print 1.2.

Comment 9

[Mike Hommey [:glandium]]

> --- a/widget/src/gtk2/nsPrintDialogGTK.cpp
> +++ b/widget/src/gtk2/nsPrintDialogGTK.cpp
> @@ -209,18 +209,16 @@ nsPrintDialogWidgetGTK::nsPrintDialogWid
(...) 
> -                      | GTK_PRINT_CAPABILITY_GENERATE_PDF
> -                      | GTK_PRINT_CAPABILITY_GENERATE_PS

IMHO it would be better to keep these set and add the SVG variant, in case Gtk+ adds yet another format (in which case not specifying anything would bring up the new unsupported format in the print dialog, like it happened when SVG was added in Gtk+)

Comment 10

[Mike Hommey [:glandium]]

BTW, the originally reported issue is gone with bug 546093. This bug is now about allowing SVG as an output format.

Comment 11

[Takeshi Kurosawa :takenspc]

Hmm, GTK+ lacks a constant to specify whether application supports SVG output.

http://library.gnome.org/devel/gtk/unstable/GtkPrintUnixDialog.html#GtkPrintCapabilities

Comment 12

[Firefox Bug Husbandry Bot]

https://bugzilla.mozilla.org/show_bug.cgi?id=1552613