gecko/layout/media
Jeff Muizelaar 6da588e57d Bug 845874. Switch to Y-X banded regions. r=roc
Previously our region code was just a simple y,x sorted list of
non-intersecting rectangles. This can cause us to have simple regions
represented in a complex unoptimizable way.

Switching to pixman regions gives us a canonical region implementation.

There are some cases when this can cause performance regressions.

For example, with the old region code we end up with this region:
http://people.mozilla.org/~jmuizelaar/region-pre.html
which is represented like this:
http://people.mozilla.org/~jmuizelaar/region-post.html
with the new code.

We call SimplifyOutward(4) on this. With old regions we can't simplify it so we
end up taking the bounds and get 1 rect. With the new regions we have only 3
rects to start and so we do nothing. The difference between 3 rects and 1 rect
cause D2D to do a PushLayer() instead of a ClipRect() and that seems to be the
causes for the regression.

--HG--
extra : rebase_source : 65e0d29d67b51a3780448eaecfde33dbcb6b99b1
2013-11-18 13:01:54 -05:00
..
webrtc Bug 935881 - Use FINAL_LIBRARY for all (fake) libraries that end up linked in a single other library. r=gps 2013-11-19 11:47:14 +09:00
Makefile.in Bug 914245 - Move FORCE_SHARED_LIB to moz.build. r=mshal 2013-11-19 11:47:45 +09:00
moz.build Bug 914245 - Move FORCE_SHARED_LIB to moz.build. r=mshal 2013-11-19 11:47:45 +09:00
symbols.def.in Bug 845874. Switch to Y-X banded regions. r=roc 2013-11-18 13:01:54 -05:00