Split out layered child stacking contexts in display lists
This patch is in preparation for more dynamic layerization of the
pieces of display lists. It also prevents having to sort the children
by z-index multiple times.
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This patch is in preparation for more dynamic layerization of the
pieces of display lists. It also prevents having to sort the children
by z-index multiple times.
layout: Rewrite whitespace stripping.
This patch makes Servo unconditionally strip whitespace before text run
scanning (assuming that the `white-space` property allows it). Whitespace
stripping during reflow is now only used for handling whitespace at the ends of
lines; reflow now never attempts to handle ignorable whitespace.
Many CSS tests pass now. There are some new failures, however.
The following reference tests now fail due to a pre-existing bug whereby
whitespace is used to calculate the position of inline hypothetical boxes for
elements with `display: inline; position: absolute`:
* `absolute-replaced-height-036.htm`
* `vertical-align-sub-001.htm`
* `vertical-align-super-001.htm`
The following reference tests fail due to a pre-existing bug whereby we don't
handle `font-size: 0` properly in inline reflow:
* `font-size-zero-1.htm`
* `font-size-zero-2.htm`
The following reference test fails due to the fact that it relied on our
incorrect insertion of whitespace to make room for the black background:
* `inline-formatting-context-007.htm`
r? @mbrubeck
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This patch makes Servo unconditionally strip whitespace before text run
scanning (assuming that the `white-space` property allows it). Whitespace
stripping during reflow is now only used for handling whitespace at the ends of
lines; reflow now never attempts to handle ignorable whitespace.
Many CSS tests pass now. There are some new failures, however.
The following reference tests now fail due to a pre-existing bug whereby
whitespace is used to calculate the position of inline hypothetical boxes for
elements with `display: inline; position: absolute`:
* `absolute-replaced-height-036.htm`
* `vertical-align-sub-001.htm`
* `vertical-align-super-001.htm`
The following reference tests fail due to a pre-existing bug whereby we don't
handle `font-size: 0` properly in inline reflow:
* `font-size-zero-1.htm`
* `font-size-zero-2.htm`
The following reference test fails due to the fact that it relied on our
incorrect insertion of whitespace to make room for the black background:
* `inline-formatting-context-007.htm`
Snap rectangles to nearest pixels consistently.
Snapping the top-left and bottom-right corners separately can cause a rectangle to change size or even become empty when offset by a subpixel amount. Instead, this patch snaps the top-left corner, then snaps the size to a whole pixel amount, so any rectangle of a given original size will always have the same snapped size.
Fixes#7152. r? @pcwalton or @glennw
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Snapping the top-left and bottom-right corners separately can cause a
rectangle to change size when offset by a subpixel amount. Instead, this
patch snaps the top-left corner, then rounds the size to a whole pixel amount,
so any rectangle of a given size will always have the same snapped size.
Fixes#7152.
Known issues:
* Display list optimization can sometimes optimize out elements that
should be shown. This affects the Enyo demo.
* The `overflow: scroll` container doesn't clip the inner layer properly
when borders, border radius, etc. are present.
* `overflow-x: scroll` and `overflow-y: scroll` don't work individually;
elements are scrolled all at once.
* Scrolling only works on absolutely-positioned elements.
new styles are set.
Tying transitions to the DOM node avoids quadratic complexity when
updating them.
Finishing transitions instantly when styles are updated makes our
behavior more correct.
