Bug 10118

Summary: Missing bitmapped characters in pdf output
Product: cairo Reporter: Timothée Lecomte <timothee.lecomte>
Component: pdf backendAssignee: Kristian Høgsberg <krh>
Status: RESOLVED FIXED QA Contact: cairo-bugs mailing list <cairo-bugs>
Severity: normal    
Priority: medium    
Version: 1.3.9   
Hardware: Other   
OS: All   
Whiteboard:
i915 platform: i915 features:

Description Timothée Lecomte 2007-02-28 00:28:40 UTC
For an image surface, pango has some sort of fallback mechanism if the select font does not contain the character I want to draw. For example, I want to display a Japanese character, and I select the "Bitstream Vera Sans" font which does not contain it, and I get a bitmapped character obviously coming from another font.
My problem is that this fallback mechanism does not seem to exist for pdf
surfaces. Instead of a bitmapped Japanese character, there is no displayed
character.

This looks like a bug. It has been reported to the cairo mailing-list, I am filling a bug report so that it doesn't get lost.

Here are pdf and image outputs of my sample application:
http://tipote.free.fr/cairopdf_utf8.pdf
http://tipote.free.fr/wxt_utf8.png

Adrian Johnson looked at the pdf output and replied:
"The bitmap font is embedded in your the PDF. The reason you can't see it
is that the bitmap glyphs have a y coordinate of -78338. I have
reproduced this problem using the mixed.pango from
http://lists.freedesktop.org/archives/cairo/2007-February/009476.html
when I don't have any Chinese TrueType fonts installed. I have confirmed
that Pango is passing in the invalid y coordinate to cairo_show_glyphs()
when using the PDF or PS surface."

It may look like a pango bug, but I'm posting this as a cairo bug since it appears with a pdf surface but not for an image surface.

Thanks for your help.

Best regards,
Timothée Lecomte

P.S.: The versions that I am using are:
cairo 1.3.12
pango 1.4.10
fontconfig 2.4.2
freetype 2.3.1
looking at the pdf with evince 0.6.1 / poppler 0.5.4
Comment 1 Behdad Esfahbod 2008-01-25 15:48:48 UTC
commit 3d2144b6af07ca44b6fbf1c96080b7e2b7c0285c
Author: Behdad Esfahbod <behdad@behdad.org>
Date:   Fri Jan 25 17:06:11 2008 -0500

    [cairo-ft] Fix font metrics computation for bitmap fonts and no metrics-hinting
    
    Preivously we were returning NAN font metrics.  Fixed now.  Makes bitmap-font
    test pass again.

Comment 2 Behdad Esfahbod 2008-01-25 15:49:11 UTC
Will be in 1.6, and in 1.4.16 if there's going to be one.

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