This reverts the following commits:
2715f2098167e3b3c53b
See this thread for an analysis of the problems it caused:
http://lists.freedesktop.org/archives/cairo/2007-February/009825.html
In short, a single cache for all backends doesn't work, as one thread
using any backend can cause an unused xlib pattern to be evicted from
the cache, and trigger an xlib call while the display is being used
from another thread. Xlib is not prepared for this.
We use a small cache of size 16 for surfaces created for solid patterns.
This mainly helps with the X backends where we don't have to create a
pattern for every operation, so we save a lot on X traffic. Xft uses a
similar cache, so cairo's text rendering traffic with the xlib backend
now completely matches that of Xft.
The cache uses an static index variable, which itself acts like a cache of
size 1, remembering the most recently used solid pattern. So repeated
lookups for the same pattern hit immediately. If that fails, the cache is
searched linearly, and if that fails too, a new surface is created and a
random member of the cache is evicted.
Only surfaces that are "compatible" are used. The definition of compatible
is backend specific. For the xlib backend, it means that the two surfaces
are allocated on the same display. Implementations for compatibility are
provided for all backends that it makes sense.
This patch was produced by running git-stripspace on all *.[ch] files
within cairo. Note that this script would have also created all the changes
from the previous commits to remove trailing whitespace.
This patch was produced with the following (GNU) sed script:
sed -i -r -e '/^[ \t]*\/?\*/ s/[ \t]+$//'
run on all *.[ch] files within cairo, (though I manually excluded
src/cairo-atsui-font.c which has a code line that appears as a comment
to this script).
Replace cairo cache implementation (this code from cworth)
No more global glyph cache to clean up
Store glyphs in new per-scaled font caches which hold user-space metrics and device space bounding boxes
Refactor glyph drawing APIs so that the surface API is invoked directly from the gstate code.
Add path creation/destruction routines (to hold glyph paths)
New implementation of scaled fonts which uses per-scaled_font caches for glyphs and keeps user-space metrics, device-space bboxes along with glyph images and/or glyph paths.
Adapt to new scaled font API changes.
New cache and scaled_font APIs
Repond to bug fix in metrics computation for glyphs where y values were rounded up instead of down because of a sign difference between cairo and FreeType.
Reviewed by: otaylor, cworth
New function to reset all static data (eg. caches) to their initial state.
Fix check-valgrind target to depend on the 'all' target.
Add check for a new, proposed, XrmFinalize function.
Add cairo-debug.c.
Move the definition of CAIRO_BEGIN_DECLS to cairo-features.h so that it can be shared between public header files, and so that it doesn't clutter cairo.h
Implement reset_static_data in all modules as required.
Call cairo_debug_reset_static_data and FcFini so that we can have all tests be valgrind-clean with respect to memory leaks and still-reachable data.
