pkg/50551: graphviz + cairo = sad

[dholland%netbsd.org@localhost]

>Number:         50551
>Category:       pkg
>Synopsis:       graphviz + cairo = sad
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Dec 14 11:15:00 +0000 2015
>Originator:     David A. Holland
>Release:        NetBSD 7.99.21 (20151120)
>Organization:
>Environment:
System: NetBSD macaran 7.99.21 NetBSD 7.99.21 (MACARAN) #31: Fri Nov 20 17:42:57 EST 2015  dholland@macaran:/usr/src/sys/arch/amd64/compile/MACARAN amd64
Architecture: x86_64
Machine: amd64
	cairo-1.14.4
	graphviz-2.38.0nb9
>Description:

If you give graphviz a graph with labels that include a "+" character
and ask it to generate PDF, it generates PDF that contains a "-"
character instead. It also generates crappy bit-aliased PDF instead of
nice properly vectorized PDF.

Generating postscript instead avoids these problems, both of which are
caused by using the Cairo output driver. (Why graphviz has a "core" ps
driver and not a "core" PDF driver is beyond me, but it is so.)

>How-To-Repeat:

   --- foo.dot ---
digraph foo {
   n1;
   n2;
   n1 -> n2 [label="1 + 1"];
}
   ------

% dot -Tpdf foo.dot > foo.pdf
% xpdf foo.pdf
observe "1 - 1" even at high magnification.

>Fix:
Beats me.