When a stacking-context is not positioned, its z-index should be
ignored. This is per CSS 2 9.9.1. The only exception to this is when
the z-index is applied to an element with display: flex | inline-flex.
inline-flex does not appear to be implemented at this time so we only
do this for flex.
Remove constellation round trip for subpage mapping in compositor.
This makes use of the new functionality that allows iframes to generate their own pipeline IDs in order to remove any knowledge of subpage ids from the compositor.
(This is the first of several commits removing subpage from parts of servo).
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This makes use of the new functionality that allows iframes to generate their own pipeline IDs in order to remove any knowledge of subpage ids from the compositor.
(This is the first of several commits removing subpage from parts of servo).
Make it possible for iframes to create their own pipeline ID.
This doesn't change any functionality, but it's the first step towards removing SubpageId.
Adding this change now will allow us to gradually change over code referencing subpage id rather than in one massive PR.
Introduces a namespace for pipeline ID generation - there is a namespace for the constellation thread, and one per script thread.
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This doesn't change any functionality, but it's the first step towards removing SubpageId.
Adding this change now will allow us to gradually change over code referencing subpage id rather than in one massive PR.
Introduces a namespace for pipeline ID generation - there is a namespace for the constellation thread, and one per script thread.
Rework how StackingContexts are dynamically added to layers
StackingContexts are added to layers when it is necessary to maintain
their ordering on top of other layered StackingContexts. Instead of
tracking the information about a layer scattered around into different
structs, combine it all into LayerInfo. LayerInfo will be used in the
future to hold layer information for DisplayItems that are layerized
independently of StackingContexts.
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StackingContexts are added to layers when it is necessary to maintain
their ordering on top of other layered StackingContexts. Instead of
tracking the information about a layer scattered around into different
structs, combine it all into LayerInfo. LayerInfo will be used in the
future to hold layer information for DisplayItems that are layerized
independently of StackingContexts.
Move some methods from RawLayoutElementHelpers to LayoutElementHelpers.
This is part of a long-term plan to ensure layout never has access to
unwrapped pointers to DOM objects. The remaining methods on the
RawLayoutElementHelpers trait are harder to move, because of the lifetimes in
their signatures.
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This is part of a long-term plan to ensure layout never has access to
unwrapped pointers to DOM objects. The remaining methods on the
RawLayoutElementHelpers trait are harder to move, because of the lifetimes in
their signatures.
Flows never care about their own text-align, only the text-align of
their parent; change the text-align flags to account for that. Make the
"align descendants" rule use the flags instead of the current node's style.
Fixes#7301.
Implement <meta name=viewport> handling
Translate <meta name=viewport> as according to [CSS Device Adaption § 9](http://dev.w3.org/csswg/css-device-adapt/#viewport-meta)
Note: as the PR currently stands, handling `<meta name=viewport>` elements always occurs. This is probably not desired for some contexts (e.g. desktop), but I'm unsure of how to conditionally handle elements based on that.
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Simplify stacking context creation
Have Fragment::create_stacking_context understand which stacking
contexts need layers and which do not. This simplifies the way it is
called and eliminates a bunch of code.
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Have Fragment::create_stacking_context understand which stacking
contexts need layers and which do not. This simplifies the way it is
called and eliminates a bunch of code.
layout: Make the compositor rather than layout determine the position of each iframe.
The old code that attempted to do this during layout wasn't able to work
for multiple reasons: it couldn't know where the iframe was going to be
on the page (because of nested iframes), and at the time it was building
the display list for a fragment it couldn't know where that fragment was
going to be in page coordinates.
This patch rewrites that code so that only the size of an iframe is
determined during layout, and the position is determined by the
compositor. Layout layerizes iframes and marks the iframe layers with
the appropriate subpage ID so that the compositor can place them
correctly.
Closes#7377.
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each iframe.
The old code that attempted to do this during layout wasn't able to work
for multiple reasons: it couldn't know where the iframe was going to be
on the page (because of nested iframes), and at the time it was building
the display list for a fragment it couldn't know where that fragment was
going to be in page coordinates.
This patch rewrites that code so that both the sizes and positions of
iframes are determined by the compositor. Layout layerizes all iframes
and marks the iframe layers with the appropriate pipeline and subpage
IDs so that the compositor can place them correctly. This approach is
similar in spirit to Gecko's `RefLayer` infrastructure. The logic that
determines when it is time to take the screenshot for reftests has been
significantly revamped to deal with this change in delegation of
responsibility.
Additionally, this code removes the infrastructure that sends layout
data back to the layout task to be destroyed, since it is now all
thread-safe and can be destroyed on the script task.
The failing tests now fail because of a pre-existing bug related to
intrinsic heights and borders on inline replaced elements. They happened
to pass before because we never rendered the iframes at all, which meant
they never had a chance to draw the red border the tests expect to not
render!
Closes#7377.
Ensure that animations expire correctly and stop compositing occurring after they finish.
There were two problems here:
(1) The animation state update function was only called when nodes were dirty or there were new animations.
(2) When all animations for a node expired, the entry from the hash table was not removed.
The result was that once an animation began, the compositor would be running as fast as it can forever.
Fixes#7721.
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There were two problems here:
(1) The animation state update function was only called when nodes were dirty or there were new animations.
(2) When all animations for a node expired, the entry from the hash table was not removed.
The result was that once an animation began, the compositor would be running as fast as it can forever.
Fixes#7721.
