[cairo] Rendering error in cairo-1.5.10 and up

[Franz Schmid]

Franz Schmid schrieb:
> Hi cairo developers,
> 
> sorry to bother you with another cairo bug. I discovered that
> in cairo-1.5.10 and up (including 1.6.4) the cairo_set_dash function
> causes rendering errors with dashed closed polygons.
> 
> Please see http://bugs.scribus.net/view.php?id=6971
> for screenshots and comments.
> 
> The only workaround for that problem is not to close the polygon,
> but that is simply not acceptable.
> 
> The last working version of cairo is 1.5.8
Got now a minimal compilable sample snippet that shows the bug.
I found out that the bug is triggered by starting the path
outside the image surface.

Compile the attached code with:
  gcc -I/usr/local/include/cairo -L/usr/local/lib -lcairo dashtest.c -o dashtest

and start it with ./dashtest it produces a small .png called dashtest.png.
When you look at the produced png you will notice a faint diagonal line in
the upper left corner. This line should definitly not exist.

Greetings,
Franz Schmid
-------------- next part --------------
A non-text attachment was scrubbed...
Name: dashtest.c
Type: text/x-csrc
Size: 872 bytes
Desc: not available
Url : http://lists.cairographics.org/archives/cairo/attachments/20080429/1d034f06/attachment.c 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: dashtest.png
Type: image/png
Size: 797 bytes
Desc: not available
Url : http://lists.cairographics.org/archives/cairo/attachments/20080429/1d034f06/attachment.png