* views are now correctly clipped when they are
(partly) hidden under their parent(s)
* removed fIsTopView, the top view in a window
simply has no parent
* introduced WindowLayer::CopyContents() which
blits part of the contents to another location,
while moving that part in the dirty regions. Since
this is currently used from the Desktop thread,
messing with the update session dirty regions
requires now to lock the clipping
* that feature is now used for blitting a view to its
new location in ViewLayer::MoveBy(), which
works for right and/or bottom aligned views just fine
* I left the global dirty region in Desktop for now,
moving it into each WindowLayer gave quite a slowdown
and caused all kinds of other problems.
* a view is now cleared to the background color right
before the first drawing command from the client
is executed for that view, this reduces flickering
a lot because the content is drawn much more shortly
after the background is cleared.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@15201 a95241bf-73f2-0310-859d-f6bbb57e9c96
Stephan Aßmus
748533bbf9