Use two levels of pthread support: a minimal level used to
build cairo itself, and a full level to build threaded apps
which want to use cairo. The minimal level tries to use
pthread stubs from libc if possible, but falls back to the
full level if that's not possible. We use CFLAGS=-D_REENTRANT
LIBS=-lpthread to find a real pthread library since that seems
to work on every unix-like test box we can get our hands on.
We were exposing the actual value of CAIRO_FORMAT_INVALID
through API functions already, so it makes sense to just
go ahead and put it in the cairo_format_t enum.
Real applications that control their Drawable externally to Cairo are
'disadvantaged' by cairo-perf-trace when it creates a similar surface
for each new instance of the same Drawable. The difficulty in
maintaining one perf surface for every application surface is that the
traces do not track lifetimes for the application surfaces, so we would
just accumulate stale surfaces. The surface cache takes a different
approach and returns the same surface for each active Drawable, and
maintains a hold-over of the MRU 16 surfaces. This achieves 60-80% hit
rate with firefox, which is probably as good as can be expected.
Obviously for double-buffered applications we only every draw to freshly
created surfaces (and Gtk+ bypasses cairo to do the final copy -- the
ideal application would just use a push-group for double buffering, in
which case we would capture and replay the entire expose event).
To enable use of the surface cache whilst replaying use -c:
./cairo-perf-trace -c firefox-talos-gfx
sphinx is an alternate version of the current cairo-test-trace. It's
purpose is to replay a live application (which may just be a replay of a
trace) against a backend and its reference. The improvement over the
original cairo-test-trace is that the reference backend may be from an
older version of cairo.