tree 17c70f72e9b573998cdfefa6e27e32945bd27093
parent ac566fe54a10c30567c9427e68ddf348c5460a3a
author Jean-Philippe Gravel <jpgravel@chromium.org> 1709066638 -0800
committer Blink WPT Bot <blink-w3c-test-autoroller@chromium.org> 1709074666 -0800

Propagate the current transform when creating a side recording

The 2D canvas uses an MemoryManagedPaintRecorder (a child class of
InspectableRecordPaintCanvas) to record draw ops because it needs to
be able to query the current matrix. InspectableRecordPaintCanvas
keeps track of the current matrix by maintaining an SkNoDrawCanvas in
parallel to the recording.

When we open a layer in the 2D canvas, we create a side recording in
which we store the layer content. This is needed so that we could
present the canvas at any time by flushing all paint ops up to the
first beginLayer (opened layers can't be flushed, they'll be presented
later, after they are closed). When creating the side recording
however, the SkNoDrawCanvas of the new recording has to be initialized
with the same matrix as the main recording, or else, the layer's
InspectableRecordPaintCanvas won't hold the correct transform.

The 2D canvas uses a MemoryManagedPaintRecorder, but the
SkNoDrawCanvas lives in the parent class,
InspectableRecordPaintCanvas. MemoryManagedPaintRecorder can't
therefore set the matrix on it's own. The SkNoDrawCanvas is an
implementation detail of InspectableRecordPaintCanvas, it would be
preferable to avoid exposing this via the class API. A better
abstraction is to add CreateChildCanvas constructors, to delegate to
the InspectableRecordPaintCanvas task of creating a canvas with the
same size and matrix.

Bug: 40249439
Change-Id: Ib3c0510e06d8f820f4d63469061546c1b140d2bf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5324650
Reviewed-by: Xianzhu Wang <wangxianzhu@chromium.org>
Commit-Queue: Jean-Philippe Gravel <jpgravel@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1266025}