Previously animation ownership was a messy split between
`AnimatedBitmapDecodedImageData` and the consumers (i.e.
`ImageStyleValueResource`, `HTMLImageElement`, and `SVGImageElement`)
with `AnimatedBitmapDecodedImageData` owning the frames and a current
frame index, and the consumers owning the rest of the state (e.g. loop
count, timers to drive the animation forward, their own current index).
This had a couple of main issues:
- While `AnimatedDecodedImageData` partially synchronized animations by
dropping unexpected advancement notifications, this didn't apply to
other animation state which meant, for instance, that a later started
consumer could drive the animation of an earlier one past the max
loop count (albeit without invalidating the earlier consumer).
- Multiple consumers didn't share frame timings, meaning animations
could be up to a full frame out of sync visually.
- Animations were paused depending on whether there were any consumers,
this is different to the behavior in other browsers (where they
continue regardless of whether there are any consumers).
- It was an overgeneralization of how animations need to work - only
`AnimatedBitmapDecodedImageData` works with an indexed frame model,
with animated SVGs (although not yet implemented) relying on their
internal event loop to be driven forward.
Given the above the new approach implemented in this commit is:
- The API for `DecodedImageData` is animation system agnostic, only
exposing `default_frame`, `current_frame`, and `restart_animation`
methods not reliant on providing a specific frame index.
- `AnimatedBitmapDecodedImageData` owns its own timer, loop count,
etc. The animation starts when the first consumer registers and ends
when the document is hidden or becomes inactive (or completes in the
case of finite animations).
- Consumers are invalidated by `AnimatedBitmapDecodedImageData` when
required.
Tests have been added for:
- Animations being paused when the document becomes inactive and
restarted when it becomes active again.
- Frame timings being synchronized across consumers.
- Restarts triggered by `HTMLImageElement` applying to all consumers.
- Processing ending once a non-infinite animation plays to completion.
The tests to ensure animations are cancelled when consumers are removed
(e.g. `animated-background-image-timer-stops-when-hidden.html`) have
been updated to assert the inverse since animation state is now per
resource not per consumer.
In a future commit, ownership of animation will be transferred from
these clients to `AnimatedDecodedImageData` and we will need a way to
invalidate them for new frames.
This also revealed some `ImageProvider`s which don't yet support
animated images (e.g. `<input type="file">`, `<object>`, etc) but that
is left as a FIXME for now.
Otherwise, the load event will block the original document until GC
runs.
Without this, media-load-task-after-adoption.html would wait for the
idle timeout to trigger a garbage collection, which could sometimes
cause the test to time out entirely.
Move the layout tree from GC allocation to refcounted ownership so
removed layout and paint subtrees are destroyed synchronously instead
of waiting for the next GC sweep. This dramatically reduces GC memory
usage peaks after layout tree churn and makes it easier for memory use
to fall back after large document updates.
Update layout factories, tree traversal, SVG layout node creation,
paintable back-pointers, and pseudo-element layout links to use RefPtr
ownership.
Make display: contents follow the same shape as Blink and WebKit: the
element itself does not create a layout node, and its children are
flattened into the nearest layout parent. Wrap direct non-whitespace
text in an anonymous inline node when the boxless element contributes
inherited style to that text.
Use an internal inline wrapper for display: contents pseudo-elements
so generated content can still participate in layout, painting, hit
testing, and pseudo-element queries. Keep CSSOM reporting the computed
display value from the pseudo style, not the internal wrapper.
Remove the retained out-of-tree layout node list and its testing hook,
since the flattened model does not need a side owner for boxless
elements. Add coverage for inherited text style, dynamic insertion
order, pseudo-element hit testing, and computed style queries.
Move ComputedProperties and CascadedProperties out of the GC. They no
longer contain strong references to GC-managed data.
Keep computed styles alive from DOM elements and animation updates with
RefPtr. Pass style into layout constructors by reference, since layout
only copies the values it needs while building nodes.
Use GC::Weak for cascade source links, so entries no longer keep the
style declaration or shadow root alive.
DecodedImageFrame only wraps a ref-counted Bitmap and color-space
metadata. The frame object itself does not provide shared mutable
state or lifetime ownership beyond those members, so ref-counting it
adds an unnecessary layer of indirection.
DecodedImageFrame now owns decoded bitmap pixels directly, so the
separate ImmutableBitmap wrapper no longer carries useful semantics.
Remove the class and pass decoded image frames or bitmaps at the
boundaries where pixels are actually required.
The Skia image cache now keys off DecodedImageFrame, matching the
display-list commands that paint decoded images. Video frames stay
owned by LibMedia, with the explicit YUV-to-bitmap conversion living
at HTMLVideoElement's decoded-frame entry point for canvas and WebGL
callers.
Decoded image data should not continue to traffic in ImmutableBitmap now
that the bitmap wrapper is being retired. Introduce DecodedImageFrame as
the paintable decoded-image unit and store a Bitmap plus ColorSpace in
it directly.
Thread the new frame type through decoded image data, display-list
image commands, filters, canvas drawImage, patterns, WebGL texture
upload, and CSS/SVG image consumers. ImmutableBitmap remains only at
the legacy boundaries that still need it, such as HTML video snapshots
and callers that explicitly ask for a bitmap snapshot.
This keeps color-space ownership with the decoded frame while making
the expensive or legacy ImmutableBitmap path explicit at the few call
sites that still need it.
Previously, the LibWeb bindings generator would output multiple per
interface files like Prototype/Constructor/Namespace/GlobalMixin
depending on the contents of that IDL file.
This complicates the build system as it means that it does not know
what files will be generated without knowledge of the contents of that
IDL file.
Instead, for each IDL file only generate a single Bindings/<IDLFile>.h
and Bindings/<IDLFile>.cpp.
Rename Document::set_needs_display() to set_needs_repaint() and make it
private. External callers must now go through Node/Paintable which
route the request to the document internally.
Fix one existing misuse in AnimationEffect that was calling
document-level set_needs_display() instead of routing through the
target element's paintable.
This is preparation for per-paintable display list command caching:
repaint requests must go through specific paintables so their cached
command lists can be invalidated.
Add unsafe_layout_node(), unsafe_paintable(), and unsafe_paintable_box()
accessors that skip layout-staleness verification. These are for use in
contexts where accessing layout/paintable data is legitimate despite
layout not being up to date: tree construction, style recalculation,
painting, animation interpolation, DOM mutation, and invalidation
propagation.
Also add wrapper APIs on Node to centralize common patterns:
- set_needs_display() wraps if (unsafe_paintable()) ...set_needs_display
- set_needs_paint_only_properties_update() wraps similar
- set_needs_layout_update() wraps if (unsafe_layout_node()) ...
And add Document::layout_is_up_to_date() which checks whether layout
tree update flags are all clear.
...and SVGDecodedImageData.h
These headers only use Document via forward-declarable references and
smart pointers. Add explicit Document.h includes to .cpp files that
were relying on the transitive include.
This ensures that we are explicitly declaring the allocator to use when
allocating a cell(-inheriting) type, instead of silently falling back
to size-based allocation.
Since this is done in allocate_cell, this will only be detected for
types that are actively being allocated. However, since that means
they're _not_ being allocated, that means it's safe to not declare
an allocator to use for those. For example, the base TypedArray<T>,
which is never directly allocated and only the defined specializations
are ever allocated.
Currently, ImageProvider::current_image_bitmap takes a Gfx::IntSize
argument which determines the size of the returned bitmap. The default
value of this argument is 0x0 which causes the function to return
nullptr. This behavior is evidently unintuitive enough that it has lead
to incorrect usage in multiple places. For example, the 2D canvas
drawImage method will never actually draw anything because it calls
current_image_bitmap with no arguments. And the naturalWidth and
naturalHeight of an image will always return 0 (even after the image has
loaded) for the same reason.
To correct this and hopefully avoid similar issues in the future,
ImageProvider::current_image_bitmap will be renamed to
current_image_bitmap_sized, and the default value for the size argument
will be removed. For consistency, a similar change will be made to
SVGImageElement::default_image_bitmap.
The existing current_image_bitmap function will no longer take a size
argument. Instead it will always return a bitmap of the image's
intrinsic size. This seems to be what most existing callers had already
assumed was the function's behavior.
An SVGLength can be read-only, e.g. all animVal values cannot be
modified. Implement this for all instantiations of SVGLength.
While we're here, add `fake_animated_length_fixme()` so we can easily
find all sites where we need to improve our animated length game.
Before this change, we were going through the chain of base classes for
each IDL interface object and having them set the prototype to their
prototype.
Instead of doing that, reorder things so that we set the right prototype
immediately in Foo::initialize(), and then don't bother in all the base
class overrides.
This knocks off a ~1% profile item on Speedometer 3.
12c6ac78e2 with fixed mistake when cache
slot is copied instead of being referenced:
```cpp
auto cache =
box.cached_intrinsic_sizes().min_content_height.ensure(width);
```
while it should've been:
```cpp
auto& cache =
box.cached_intrinsic_sizes().min_content_height.ensure(width);
```
This change moves intrinsic sizes cache from
LayoutState, which is local to current layout run,
to layout nodes, so it could be reused between
layout runs. This optimization is possible because
we can guarantee that these measurements will
remain unchanged unless the style of the element
or any of its descendants changes.
For now, invalidation is implemented simply by
resetting cache on whole ancestors chain once we
figured that element needs layout update.
The case when layout is invalidated by DOM's
structural changes is covered by layout tree
invalidation that drops intrinsic sizes cache
along with layout nodes.
I measured improvement on couple websites:
- Mail list on GMail 28ms -> 6ms
- GitHub large code page 47ms -> 36ms
- Discord chat history 15ms -> 8ms
(Time does not include `commit()`)
This reduces the number of `.cpp` files that need to be recompiled when
one of the below header files changes as follows:
Painting/Command.h: 1030 -> 61
Painting/DisplayList.h: 1030 -> 60
Painting/DisplayListRecorder.h: 557 -> 59
Resulting in a massive rename across almost everywhere! Alongside the
namespace change, we now have the following names:
* JS::NonnullGCPtr -> GC::Ref
* JS::GCPtr -> GC::Ptr
* JS::HeapFunction -> GC::Function
* JS::CellImpl -> GC::Cell
* JS::Handle -> GC::Root
We currently have 2 virtual methods to inform DOM::Element subclasses
when an attribute has changed, one of which is spec-compliant. This
patch removes the non-compliant variant.
Now that the heap has no knowledge about a JavaScript realm and is
purely for managing the memory of the heap, it does not make sense
to name this function to say that it is a non-realm variant.
