- Mouse wheel events synthesized by OSX for momentum scrolling can now
be interrupted by DOM triggered and CSS scroll snapping triggered scroll
events for consistent behavior with the scrolling and fling gestures
in the APZC.
- ScrollbarStyles now carries additional variables to support new
CSS scroll snapping attributes:
- scroll-snap-type / scroll-snap-type-x / scroll-snap-type-y
- scroll-snap-points-x / scroll-snap-points-y
- scroll-snap-destination
- (scroll-snap-coordinate does not apply to the scroll container)
- Simplified the constructor and operator== for ScrollbarStyles.
The first failure in rc1 was:
TEST-UNEXPECTED-FAIL | testAxisLocking | PaintExpecter - blockUtilClear timeout
and the first failure in rc2 (API9) or rc3 (API11) was:
TEST-UNEXPECTED-FAIL | testPanCorrectness | PaintExpecter - blockUtilClear timeout
This makes APZ behave nicely with most uses of a css transform:scale.
Summary of changes:
- FrameMetrics::mCumulativeResolution now includes the css-driven resolution
in addition to the pres-shell resolution.
- Displayports are now stored in Screen pixels rather than Layer pixels.
This is what we want anyways (as we'd like the displayport size to remain
constant as a fraction of the screen size), but it was necessary to make
this change as part of this patch because continuing to store them in
Layer pixels in the presence of a css-driven resolution would have
required a bunch of infrastructure to implement correctly.
Remaining work:
- Layout painting a scrollable layer at a resolution different from the
scale induced by the css transform causes problems. These will go away
with bug 1076192.
- Different resolutions on the x and y axes are not supported. This is
tracked by bug 1039967.
This makes APZ behave nicely with most uses of a css transform:scale.
Summary of changes:
- FrameMetrics::mCumulativeResolution now includes the css-driven resolution
in addition to the pres-shell resolution.
- Displayports are now stored in Screen pixels rather than Layer pixels.
This is what we want anyways (as we'd like the displayport size to remain
constant as a fraction of the screen size), but it was necessary to make
this change as part of this patch because continuing to store them in
Layer pixels in the presence of a css-driven resolution would have
required a bunch of infrastructure to implement correctly.
Remaining work:
- Layout painting a scrollable layer at a resolution different from the
scale induced by the css transform causes problems. These will go away
with bug 1076192.
- Different resolutions on the x and y axes are not supported. This is
tracked by bug 1039967.
- Added SCROLL_SMOOTH_AUTO flag to nsIPresShell to enable selection of
scroll behavior through CSS.
- Updated Element and Window scrolling DOM methods to enable smooth scrolling
set through the scroll-behavior CSS property.
- Keyboard, scroll bar, mousewheel, and any other events that scroll smoothly
with the general.smoothScroll preference enabled will now scroll instantly
if the scroll frame has "scroll-behavior: instant" applied through CSS.
